On Thu, 20 Dec 2018 22:22:41 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 21:50:21 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:04:01 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 17:13:52 -0000, trader_4
wrote:

On Thursday, December 20, 2018 at 12:07:40 PM UTC-5, William Gothberg
wrote:
On Thu, 20 Dec 2018 16:25:22 -0000, trader_4
wrote:

On Thursday, December 20, 2018 at 7:29:53 AM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 11:57:01 -0000, whisky-dave
wrote:

On Wednesday, 19 December 2018 16:35:05 UTC, William Gothberg
wrote:
On Wed, 19 Dec 2018 16:21:41 -0000, Mark Lloyd

wrote:

On 12/19/18 6:01 AM, William Gothberg wrote:

[snip]

They probably are fairly crude. I know they flicker, for
example if I
use my cordless drill, the chuck appears to spin the wrong
way
under the
LED lighting.
I remember seeing that with a washing machine (under
fluorescent
lights). As the tub was slowing down, the row of holes
around
the tub
would appear to reverse direction. Same thing with (spoked)
wagon wheels
in movies.

It looks absolutely ridiculous with modern cars with LED
headlights in films. How hard can it be to put a smoothing
capacitor on the output of the power supply?

It's easy but that isn't the point. The most efficient way of
driving to make maximium power into the LED means yuo have to
pulse the LED's. Using a capcitor to smooth out the DC is yet
another mode of inefficincy as it would get warm due to current
flow. Indictors in series might be better but then you run the
risk
of 'radio' interference.

Being inefficient would presumably make it impossible to get
enough
brightness out of LEDs that fit into the lamp holder. The LEDs
would
get too hot trying to give out enough brightness for a car
headlight.

However cars vary a lot, some are easy to detect flickering, some
difficult, and some impossible (with the naked eye). Perhaps
they
just use a higher frequency?

Taillights are pretty bad on a lot of cars, as they dim the
brakelights by deliberately flickering them.

Either you have eyes that are way more sensitive to this or you're
in
a
country that uses different car lights than here in the USA.
There
are a lot of cars with LED lighting, headlights and rear lights,
and
I've never noticed this flickering, nor have I ever heard it
mentioned
before this thread. I haven't noticed flickering from any LED
lights
I've used either.

I can see flicker on a 60Hz CRT monitor, but not on a 90Hz one, so
that'll give you an idea on how good my eyes are.

Can you see flicker on tailliights if you scan your eyes across the
scene?

Like I said, I haven't noticed it in the driving I've done. Nor have
I
heard anyone else mention it. Next time I come across a car that has
LEDs I'll look more closely and see if I can see anything. If just
scanning reveals it, you;d think a lot of people would be noticing
it.
Scanning is a part of driving.

I'd estimate about 1 in 5 people can see it,

Its nothing like that high and we know that because nothing
like that many saw any flickering with fluorescent lights.

Er.... most people I know can see fluorescent flicker. It doesn't annoy
most of them, but they can detect it.

Don't believe it. I did have someone at work who could
see it and was asking about how to get it fixed but no
one else could see what she was talking about.

About 20 years ago I worked where everyone had a cheap 14" CRT monitor
running at 60Hz. They really bugged me with the flicker. When I asked
everyone about them, 80% couldn't see it, 10% said they were as annoyed as
me, and 10% only saw it if they looked for it. For the 10% and the 10%, I
bought some nice 90Hz Iiyama Vision Master Pro CRT monitors. They
absolutely loved them. The other 80% couldn't see what the fuss was
about, and most of them had specs or were older.

One in five people I know could see 60Hz monitor flickering.

Don't believe that either and I never had anyone complaining about it.

And about the same can see car lights flickering.

Don't believe that either and clearly the designers can't.

A quick google search shows many many people don't like car flicker.
Millions of results.

similar to how many can see flicker on a 60Hz CRT computer monitor.

Nothing even remotely like 1 in 5 can see that.

You must know some people with really ****ty eyesight.

I'm talking about everyone at work. NOT ONE could see that.

What age group were they in?

All of the, everything from those straight out
of school to those who were about to retire.
And the kids of many of them as well.

How odd. I can't believe Aussies have different eyes to Brits. More sunlight in the room maybe? Having 90Hz CRTs to avoid flicker was quite common around the world, go google it.

I noticed that more people who were younger and/or didn't wear specs
could
see the flicker.

Don't buy that either. None of the kids could see it.

Even a colleague who never noticed it before when he looked at one of the
new 90Hz monitors immediately remarked "that picture's really stable!"

Don't most cars have LEDs now? Or does your area have a lot of older
cars? People (stupidly) around here seem to like cars that are no
more
than 10 years old. I don't think many cars after 2008 had bulbs.

Searching for "LED tail light flicker" without the quotes in google
produces 4.5 million results!

On 2018-12-20 3:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating.* I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running.* 3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try replacing
it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling).* Loads of
them
get bulged caps after a while, in particular a 3A PSU I ran 2A of LEDs
24/7 from, failed in 1 year.* It kept cutting out - I discovered the
bulk
capacitor had dried out.* Same happened (over a longer period) with two
monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not a
capacitor dropper.* Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't
cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model).* It has a basic SMPS inside it.* They're 9W and £4 each for
the
whole lamp.* I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

Think its just the way leds fail naturally
with the higher powered lighting leds.

What's quite weird is with the decent strips I've got, the LEDs are
wired in pairs.* Each pair is in parallel, then there are 20 such pairs
in series.* When one single LED fails, I'd expect either it shorts and
the neighbouring one in the pair gets 0 volts, or it fails open circuit
and the neighbouring one gets double current and soon dies.* But neither
happens.* The neighbouring LED stays lit at the same brightness.* Any
idea how this is possible?* Could the dead LED still have the same
current going through it?

And I think the LED failures are due to heat.* I now run them with the
diffuser covers off to let them be cooler.* I get more light out of them
too, and I think they look better when you can see all the dots.

I'm not rapt in that result with the led strips,
particularly with the reflection off glass etc.
I havent gotten around to mounting them
properly yet, mainly because for some
reason Bunnings doesn't stock the
extrusions to mount them in in the
very long 3-4M strips and those arent
feasible to buy online in those lengths.
Bit too crude imo to have a series of 1M ones.

I use something like these:
http://www.ebay.co.uk/itm/183429947350

All I need is to screw a small clip every 2 feet into the ceiling, and
have a plug with 240V at the end.* The strips plug into each other as
many as I need, and just clip onto the clips.

I do plan to have diffusers for those led
strips to fix the bright reflection of the
individual leds off the glass like the
front of the microwaves and wall oven
and windows.

Not sure why that would be a problem, I quite like those reflections.
Same kinda idea as people liking bright halogen uplighters instead of a
more even light throughout the room.

If I wanted a more even light, I'd have to keep the diffusers on, but
the LEDs don't last so long.* I guess I could dim them a bit instead.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space.* "Corn on the cob LED lights"
they're
called.

I don't use those, use the Hue E27 bulbs.

I only have a couple, to fit into existing bayonet fittings, but most of
my house is now the strips I linked to above.* Also means nothing hangs
down from the ceiling and can get knocked.* Plus since the light comes
from the whole strip, no shadows from myself when I'm trying to work on
something.

I could literally fit a cap about 50 times the size of the one that's in
it.* It's probably enough smoothing with the original size, I can't
remember if it flickered when I bought it.* But clearly the cap was
overworked as it failed, so I'll fit something larger so it lasts longer
this time.

Might well just be a low quality cap, not over worked.
Rectifier caps don't get overworked when not enough uF.

Maybe it's not a low ESR cap?* Maybe the high temperature in there
shortens its life?* Same thing happens in my PSUs for monitors.

For the good ones, the only problem I can foresee with the external
smoother, is overloading the lamp's bridge rectifier, as it will
only be
conducting on two of the four diodes.

Should still be fine, most bridges in that situation are used
very conservitably and the diodes are rated for the initial
turn on surge current.

There's a current limiting resistor before them.

But the current rating would be vastly lower than the surge rating.

If I was to go ahead, I think I'd run one on the bench and check the
temperature of the diodes in normal operation.

They'll be fine at that current.

If they're not very warm then they won't mind double the current.

Don't those diodes handle surges anyway?

Yeah, the surge rating is massive.

I mean a 3A diode will take way more than that for a fraction of a
second.

Yep.

It's the heat that kills them.

Not with bridges.

So why don't they just fit what they need to instead of bigger ones?

The bigger ones are the same price.

Its only when you got to the big ones
potted in a square aluminium thing with
a bolt hole in them that the price increases.

that's a trimmer

On Fri, 21 Dec 2018 09:22:41 +1100, cantankerous trolling geezer Rot Speed,
the auto-contradicting senile sociopath, blabbered, again:

FLUSH another 173 lines of absolutely idiotic troll**** unread again

--
about senile Rot Speed:
"This is like having a conversation with someone with brain damage."
MID:

On Fri, 21 Dec 2018 09:14:31 +1100, cantankerous trolling geezer Rot Speed,
the auto-contradicting senile sociopath, blabbered, again:

FLUSH anothr 203 lines of absolutely idiotic troll **** unread again

--
Another typical retarded conversation between our two village idiots,
Birdbrain and Rot Speed:

Birdbrain: "You beat me to it. Plain sex is boring."

Senile Rot: "Then **** the cats. That wont be boring."

Birdbrain: "Sell me a de-clawing tool first."

Senile Rot: "Wont help with the teeth."

Birdbrain: "They've never gone for me with their mouths."

Rot Speed: "They will if you are stupid enough to try ****ing them."

Birdbrain: "No, they always use claws."

Rot Speed: "They wont if you try ****ing them. Try it and see."

Message-ID:

On Thu, 20 Dec 2018 22:56:19 -0000, % wrote:

On 2018-12-20 3:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating. I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running. 3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try replacing
it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling). Loads of
them
get bulged caps after a while, in particular a 3A PSU I ran 2A of LEDs
24/7 from, failed in 1 year. It kept cutting out - I discovered the
bulk
capacitor had dried out. Same happened (over a longer period) with two
monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not a
capacitor dropper. Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't
cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

Think its just the way leds fail naturally
with the higher powered lighting leds.

What's quite weird is with the decent strips I've got, the LEDs are
wired in pairs. Each pair is in parallel, then there are 20 such pairs
in series. When one single LED fails, I'd expect either it shorts and
the neighbouring one in the pair gets 0 volts, or it fails open circuit
and the neighbouring one gets double current and soon dies. But neither
happens. The neighbouring LED stays lit at the same brightness. Any
idea how this is possible? Could the dead LED still have the same
current going through it?

And I think the LED failures are due to heat. I now run them with the
diffuser covers off to let them be cooler. I get more light out of them
too, and I think they look better when you can see all the dots.

I'm not rapt in that result with the led strips,
particularly with the reflection off glass etc.
I havent gotten around to mounting them
properly yet, mainly because for some
reason Bunnings doesn't stock the
extrusions to mount them in in the
very long 3-4M strips and those arent
feasible to buy online in those lengths.
Bit too crude imo to have a series of 1M ones.

I use something like these:
http://www.ebay.co.uk/itm/183429947350

All I need is to screw a small clip every 2 feet into the ceiling, and
have a plug with 240V at the end. The strips plug into each other as
many as I need, and just clip onto the clips.

I do plan to have diffusers for those led
strips to fix the bright reflection of the
individual leds off the glass like the
front of the microwaves and wall oven
and windows.

Not sure why that would be a problem, I quite like those reflections.
Same kinda idea as people liking bright halogen uplighters instead of a
more even light throughout the room.

If I wanted a more even light, I'd have to keep the diffusers on, but
the LEDs don't last so long. I guess I could dim them a bit instead.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space. "Corn on the cob LED lights"
they're
called.

I don't use those, use the Hue E27 bulbs.

I only have a couple, to fit into existing bayonet fittings, but most of
my house is now the strips I linked to above. Also means nothing hangs
down from the ceiling and can get knocked. Plus since the light comes
from the whole strip, no shadows from myself when I'm trying to work on
something.

I could literally fit a cap about 50 times the size of the one that's in
it. It's probably enough smoothing with the original size, I can't
remember if it flickered when I bought it. But clearly the cap was
overworked as it failed, so I'll fit something larger so it lasts longer
this time.

Might well just be a low quality cap, not over worked.
Rectifier caps don't get overworked when not enough uF.

Maybe it's not a low ESR cap? Maybe the high temperature in there
shortens its life? Same thing happens in my PSUs for monitors.

For the good ones, the only problem I can foresee with the external
smoother, is overloading the lamp's bridge rectifier, as it will
only be
conducting on two of the four diodes.

Should still be fine, most bridges in that situation are used
very conservitably and the diodes are rated for the initial
turn on surge current.

There's a current limiting resistor before them.

But the current rating would be vastly lower than the surge rating.

If I was to go ahead, I think I'd run one on the bench and check the
temperature of the diodes in normal operation.

They'll be fine at that current.

If they're not very warm then they won't mind double the current.

Don't those diodes handle surges anyway?

Yeah, the surge rating is massive.

I mean a 3A diode will take way more than that for a fraction of a
second.

Yep.

It's the heat that kills them.

Not with bridges.

So why don't they just fit what they need to instead of bigger ones?

The bigger ones are the same price.

Its only when you got to the big ones
potted in a square aluminium thing with
a bolt hole in them that the price increases.

that's a trimmer

No, a trimmer is an adjustable resistor/capacitor/inductor:
https://en.wikipedia.org/wiki/Trimmer_(electronics)
Rod was talking about a very large diode.

On Thu, 20 Dec 2018 21:53:44 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:25:45 -0000, % wrote:

On 2018-12-20 1:56 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 20:40:26 -0000, % wrote:

On 2018-12-20 1:30 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central heating. I'm looking inside the flickery lamp just now (£15,
20W). Without undoing the glue holding the PSU onto the inside of it,
all I can see is probably: the mains going through a large bipolar
cap,
a tiny resistor (to discharge it safely?), a bridge rectifier, another
very large resister (to limit the LED current more accurately?),
then a
400V 4.7uF capacitor (which is bulged). A capacitor dropper with a
rectifier and smoothing capacitor after it? The one I made has no
smoothing cap, just mains to cap to resistor to bridge to LED.
Perhaps
this bulged cap is why I'm getting flicker, I'll try replacing it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap? I just bought a 12V 6A SMPS
for £4.50. Designed for powering LEDs - but I've looked inside it and
it's definitely a switched mode, not a capacitor dropper. Now this
flickery LED lamp I'm looking inside, it's about 20W, so 12V at 2A is
all that's required, it could have had an SMPS in it similar to the
one
I just described.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because when some LEDs fail short circuit (it has about 40 in series),
the voltage coming from the PSU drops, to maintain the correct current
for the remaining good LEDs.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.
Better
(as I only have a few crap ones) to stick a bigger smoothing cap
inside
those. For the good ones, the only problem I can foresee with the
external smoother, is overloading the lamp's bridge rectifier, as it
will only be conducting on two of the four diodes.

The cheap **** LED lamp I have that actually flashes at 100Hz would
most
likely get much brighter and burn out, so I'd have to adjust that,
but the
others which only flicker 8% would just get 4% brighter.

you could use being 4 % brighter

That would make my IQ 140.

Was the above too difficult for you to discuss?

I Q's are the lamest oldest forgotten tests of them all ,

You're just jealous.

are you excited this is going to be how usenet is for you for the next
20 - 30 years

Be more specific.

no and start getting used to the idea that i don't do what you order

No point in you telling me something if you won't back it up.

On Thu, 20 Dec 2018 21:52:55 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:40:48 -0000, % wrote:

On 2018-12-20 2:38 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:04:01 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 17:13:52 -0000, trader_4
wrote:

On Thursday, December 20, 2018 at 12:07:40 PM UTC-5, William Gothberg
wrote:
On Thu, 20 Dec 2018 16:25:22 -0000, trader_4
wrote:

On Thursday, December 20, 2018 at 7:29:53 AM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 11:57:01 -0000, whisky-dave
wrote:

On Wednesday, 19 December 2018 16:35:05 UTC, William Gothberg
wrote:
On Wed, 19 Dec 2018 16:21:41 -0000, Mark Lloyd

wrote:

On 12/19/18 6:01 AM, William Gothberg wrote:

[snip]

They probably are fairly crude. I know they flicker, for
example if I
use my cordless drill, the chuck appears to spin the wrong
way
under the
LED lighting.
I remember seeing that with a washing machine (under
fluorescent
lights). As the tub was slowing down, the row of holes
around
the tub
would appear to reverse direction. Same thing with (spoked)
wagon wheels
in movies.

It looks absolutely ridiculous with modern cars with LED
headlights in films. How hard can it be to put a smoothing
capacitor on the output of the power supply?

It's easy but that isn't the point. The most efficient way of
driving to make maximium power into the LED means yuo have to
pulse the LED's. Using a capcitor to smooth out the DC is yet
another mode of inefficincy as it would get warm due to current
flow. Indictors in series might be better but then you run the
risk
of 'radio' interference.

Being inefficient would presumably make it impossible to get
enough
brightness out of LEDs that fit into the lamp holder. The LEDs
would
get too hot trying to give out enough brightness for a car
headlight.

However cars vary a lot, some are easy to detect flickering, some
difficult, and some impossible (with the naked eye). Perhaps
they
just use a higher frequency?

Taillights are pretty bad on a lot of cars, as they dim the
brakelights by deliberately flickering them.

Either you have eyes that are way more sensitive to this or
you're in
a
country that uses different car lights than here in the USA.
There
are a lot of cars with LED lighting, headlights and rear
lights, and
I've never noticed this flickering, nor have I ever heard it
mentioned
before this thread. I haven't noticed flickering from any LED
lights
I've used either.

I can see flicker on a 60Hz CRT monitor, but not on a 90Hz one, so
that'll give you an idea on how good my eyes are.

Can you see flicker on tailliights if you scan your eyes across the
scene?

Like I said, I haven't noticed it in the driving I've done. Nor
have I
heard anyone else mention it. Next time I come across a car that has
LEDs I'll look more closely and see if I can see anything. If just
scanning reveals it, you;d think a lot of people would be noticing
it.
Scanning is a part of driving.

I'd estimate about 1 in 5 people can see it,

Its nothing like that high and we know that because nothing
like that many saw any flickering with fluorescent lights.

Er.... most people I know can see fluorescent flicker. It doesn't annoy
most of them, but they can detect it. One in five people I know could
see 60Hz monitor flickering. And about the same can see car lights
flickering.

similar to how many can see flicker on a 60Hz CRT computer monitor.

Nothing even remotely like 1 in 5 can see that.

You must know some people with really ****ty eyesight. I noticed that
more people who were younger and/or didn't wear specs could see the
flicker.

Don't most cars have LEDs now? Or does your area have a lot of older
cars? People (stupidly) around here seem to like cars that are no
more
than 10 years old. I don't think many cars after 2008 had bulbs.

Searching for "LED tail light flicker" without the quotes in google
produces 4.5 million results!

the same thing happens when i type your name and add the words gutless
idgit

Cite link.

you don't know how to type your name , come off it

Your name is not %

On Thu, 20 Dec 2018 21:51:48 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed
wrote:

"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating. I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V 4..7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running. 3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try
replacing it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump..

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling). Loads of
them get bulged caps after a while, in particular a 3A PSU I ran 2A of
LEDs 24/7 from, failed in 1 year. It kept cutting out - I discovered
the bulk capacitor had dried out. Same happened (over a longer period)
with two monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not a
capacitor dropper. Now this flickery LED lamp I'm looking inside, it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for the
whole lamp. I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

And I think the LED failures are due to heat. I now run them with the
diffuser covers off to let them be cooler. I get more light out of them
too, and I think they look better when you can see all the dots.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space. "Corn on the cob LED lights"
they're called. I could literally fit a cap about 50 times the size of
the one that's in it. It's probably enough smoothing with the original
size, I can't remember if it flickered when I bought it. But clearly
the cap was overworked as it failed, so I'll fit something larger so it
lasts longer this time.

For the good ones, the only problem I can foresee with the external
smoother, is overloading the lamp's bridge rectifier, as it will only be
conducting on two of the four diodes.

Should still be fine, most bridges in that situation are used
very conservitably and the diodes are rated for the initial
turn on surge current.

There's a current limiting resistor before them.

If I was to go ahead, I think I'd run one on the bench and check the
temperature of the diodes in normal operation. If they're not very warm
then they won't mind double the current.

Don't those diodes handle surges anyway? I mean a 3A diode will take
way more than that for a fraction of a second. It's the heat that kills
them. So why don't they just fit what they need to instead of bigger ones?

trimmers , you need trimmers

An adjustable diode? I'm quite sure you know nothing about what you're talking.

On 2018-12-20 4:15 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 22:56:19 -0000, % wrote:

On 2018-12-20 3:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a
bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating.* I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it,
all I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor
after it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to
resistor to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was
running.* 3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try
replacing
it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling).* Loads of
them
get bulged caps after a while, in particular a 3A PSU I ran 2A of LEDs
24/7 from, failed in 1 year.* It kept cutting out - I discovered the
bulk
capacitor had dried out.* Same happened (over a longer period) with
two
monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the
flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode,
not a
capacitor dropper.* Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't
cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model).* It has a basic SMPS inside it.* They're 9W and £4 each for
the
whole lamp.* I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

Think its just the way leds fail naturally
with the higher powered lighting leds.

What's quite weird is with the decent strips I've got, the LEDs are
wired in pairs.* Each pair is in parallel, then there are 20 such pairs
in series.* When one single LED fails, I'd expect either it shorts and
the neighbouring one in the pair gets 0 volts, or it fails open circuit
and the neighbouring one gets double current and soon dies.* But neither
happens.* The neighbouring LED stays lit at the same brightness.* Any
idea how this is possible?* Could the dead LED still have the same
current going through it?

And I think the LED failures are due to heat.* I now run them with the
diffuser covers off to let them be cooler.* I get more light out of
them
too, and I think they look better when you can see all the dots.

I'm not rapt in that result with the led strips,
particularly with the reflection off glass etc.
I havent gotten around to mounting them
properly yet, mainly because for some
reason Bunnings doesn't stock the
extrusions to mount them in in the
very long 3-4M strips and those arent
feasible to buy online in those lengths.
Bit too crude imo to have a series of 1M ones.

I use something like these:
http://www.ebay.co.uk/itm/183429947350

All I need is to screw a small clip every 2 feet into the ceiling, and
have a plug with 240V at the end.* The strips plug into each other as
many as I need, and just clip onto the clips.

I do plan to have diffusers for those led
strips to fix the bright reflection of the
individual leds off the glass like the
front of the microwaves and wall oven
and windows.

Not sure why that would be a problem, I quite like those reflections.
Same kinda idea as people liking bright halogen uplighters instead of a
more even light throughout the room.

If I wanted a more even light, I'd have to keep the diffusers on, but
the LEDs don't last so long.* I guess I could dim them a bit instead.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space.* "Corn on the cob LED lights"
they're
called.

I don't use those, use the Hue E27 bulbs.

I only have a couple, to fit into existing bayonet fittings, but most of
my house is now the strips I linked to above.* Also means nothing hangs
down from the ceiling and can get knocked.* Plus since the light comes
from the whole strip, no shadows from myself when I'm trying to work on
something.

I could literally fit a cap about 50 times the size of the one
that's in
it.* It's probably enough smoothing with the original size, I can't
remember if it flickered when I bought it.* But clearly the cap was
overworked as it failed, so I'll fit something larger so it lasts
longer
this time.

Might well just be a low quality cap, not over worked.
Rectifier caps don't get overworked when not enough uF.

Maybe it's not a low ESR cap?* Maybe the high temperature in there
shortens its life?* Same thing happens in my PSUs for monitors.

For the good ones, the only problem I can foresee with the external
smoother, is overloading the lamp's bridge rectifier, as it will
only be
conducting on two of the four diodes.

Should still be fine, most bridges in that situation are used
very conservitably and the diodes are rated for the initial
turn on surge current.

There's a current limiting resistor before them.

But the current rating would be vastly lower than the surge rating.

If I was to go ahead, I think I'd run one on the bench and check the
temperature of the diodes in normal operation.

They'll be fine at that current.

If they're not very warm then they won't mind double the current.

Don't those diodes handle surges anyway?

Yeah, the surge rating is massive.

I mean a 3A diode will take way more than that for a fraction of a
second.

Yep.

It's the heat that kills them.

Not with bridges.

So why don't they just fit what they need to instead of bigger ones?

The bigger ones are the same price.

Its only when you got to the big ones
potted in a square aluminium thing with
a bolt hole in them that the price increases.

that's a trimmer

No, a trimmer is an adjustable resistor/capacitor/inductor:
https://en.wikipedia.org/wiki/Trimmer_(electronics)
Rod was talking about a very large diode.

no its not

On 2018-12-20 4:15 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:53:44 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:25:45 -0000, % wrote:

On 2018-12-20 1:56 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 20:40:26 -0000, % wrote:

On 2018-12-20 1:30 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a
bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central heating.* I'm looking inside the flickery lamp just now
(£15,
20W).* Without undoing the glue holding the PSU onto the inside
of it,
all I can see is probably: the mains going through a large bipolar
cap,
a tiny resistor (to discharge it safely?), a bridge rectifier,
another
very large resister (to limit the LED current more accurately?),
then a
400V 4.7uF capacitor (which is bulged).* A capacitor dropper with a
rectifier and smoothing capacitor after it?* The one I made has no
smoothing cap, just mains to cap to resistor to bridge to LED.
Perhaps
this bulged cap is why I'm getting flicker, I'll try replacing it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?* I just bought a 12V 6A
SMPS
for £4.50.* Designed for powering LEDs - but I've looked inside
it and
it's definitely a switched mode, not a capacitor dropper.* Now this
flickery LED lamp I'm looking inside, it's about 20W, so 12V at
2A is
all that's required, it could have had an SMPS in it similar to the
one
I just described.

I'm now looking inside one of the better LED lamps (the non-flickery
model).* It has a basic SMPS inside it.* They're 9W and £4 each for
the
whole lamp.* I'm sure it's more than just a standard SMPS though,
because when some LEDs fail short circuit (it has about 40 in
series),
the voltage coming from the PSU drops, to maintain the correct
current
for the remaining good LEDs.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.
Better
(as I only have a few crap ones) to stick a bigger smoothing cap
inside
those.* For the good ones, the only problem I can foresee with the
external smoother, is overloading the lamp's bridge rectifier, as it
will only be conducting on two of the four diodes.

The cheap **** LED lamp I have that actually flashes at 100Hz
would
most
likely get much brighter and burn out, so I'd have to adjust that,
but the
others which only flicker 8% would just get 4% brighter.

you could use being 4 % brighter

That would make my IQ 140.

Was the above too difficult for you to discuss?

I Q's are the lamest oldest forgotten tests of them all ,

You're just jealous.

are you excited this is going to be how usenet is for you for the next
20 - 30 years

Be more specific.

no and start getting used to the idea that i don't do what you order

No point in you telling me something if you won't back it up.

say it to my face and we'll see about back up

On 2018-12-20 4:16 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:52:55 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:40:48 -0000, % wrote:

On 2018-12-20 2:38 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:04:01 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 17:13:52 -0000, trader_4
wrote:

On Thursday, December 20, 2018 at 12:07:40 PM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 16:25:22 -0000, trader_4

wrote:

On Thursday, December 20, 2018 at 7:29:53 AM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 11:57:01 -0000, whisky-dave
wrote:

On Wednesday, 19 December 2018 16:35:05 UTC, William Gothberg
wrote:
On Wed, 19 Dec 2018 16:21:41 -0000, Mark Lloyd

wrote:

On 12/19/18 6:01 AM, William Gothberg wrote:

[snip]

They probably are fairly crude.* I know they flicker, for
example if I
use my cordless drill, the chuck appears to spin the
wrong
way
under the
LED lighting.
I remember seeing that with a washing machine (under
fluorescent
lights). As the tub was slowing down, the row of holes
around
the tub
would appear to reverse direction. Same thing with
(spoked)
wagon wheels
in movies.

It looks absolutely ridiculous with modern cars with LED
headlights in films.* How hard can it be to put a smoothing
capacitor on the output of the power supply?

It's easy but that isn't the point. The most efficient way of
driving to make maximium power* into the LED means yuo
have to
pulse the LED's. Using a capcitor to smooth out the DC is yet
another mode of inefficincy as it would get warm due to
current
flow. Indictors in series might be better but then you run
the
risk
of 'radio' interference.

Being inefficient would presumably make it impossible to get
enough
brightness out of LEDs that fit into the lamp holder.* The LEDs
would
get too hot trying to give out enough brightness for a car
headlight.

However cars vary a lot, some are easy to detect flickering,
some
difficult, and some impossible (with the naked eye).* Perhaps
they
just use a higher frequency?

Taillights are pretty bad on a lot of cars, as they dim the
brakelights by deliberately flickering them.

Either you have eyes that are way more sensitive to this or
you're in
a
country that uses different car lights than here in the USA.
There
are a lot of cars with LED lighting, headlights and rear
lights, and
I've never noticed this flickering, nor have I ever heard it
mentioned
before this thread.* I haven't noticed flickering from any LED
lights
I've used either.

I can see flicker on a 60Hz CRT monitor, but not on a 90Hz one, so
that'll give you an idea on how good my eyes are.

Can you see flicker on tailliights if you scan your eyes across
the
scene?

Like I said, I haven't noticed it in the driving I've done.* Nor
have I
heard anyone else mention it.* Next time I come across a car
that has
LEDs I'll look more closely and see if I can see anything.* If just
scanning reveals it, you;d think a lot of people would be noticing
it.
Scanning is a part of driving.

I'd estimate about 1 in 5 people can see it,

Its nothing like that high and we know that because nothing
like that many saw any flickering with fluorescent lights.

Er.... most people I know can see fluorescent flicker.* It doesn't
annoy
most of them, but they can detect it.* One in five people I know could
see 60Hz monitor flickering.* And about the same can see car lights
flickering.

similar to how many can see flicker on a 60Hz CRT computer monitor.

Nothing even remotely like 1 in 5 can see that.

You must know some people with really ****ty eyesight.* I noticed that
more people who were younger and/or didn't wear specs could see the
flicker.

Don't most cars have LEDs now?* Or does your area have a lot of
older
cars?* People (stupidly) around here seem to like cars that are no
more
than 10 years old.* I don't think many cars after 2008 had bulbs.

Searching for "LED tail light flicker" without the quotes in google
produces 4.5 million results!

the same thing happens when i type your name and add the words gutless
idgit

Cite link.

you don't know how to type your name , come off it

Your name is not %

yes it is but that's off topic right now ,
right now we're talking about your admission you can't spell yours

On 2018-12-20 4:16 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:51:48 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating.* I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running.* 3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try
replacing it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling).* Loads of
them get bulged caps after a while, in particular a 3A PSU I ran 2A of
LEDs 24/7 from, failed in 1 year.* It kept cutting out - I discovered
the bulk capacitor had dried out.* Same happened (over a longer period)
with two monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not a
capacitor dropper.* Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model).* It has a basic SMPS inside it.* They're 9W and £4 each for
the
whole lamp.* I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

And I think the LED failures are due to heat.* I now run them with the
diffuser covers off to let them be cooler.* I get more light out of them
too, and I think they look better when you can see all the dots.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space.* "Corn on the cob LED lights"
they're called.* I could literally fit a cap about 50 times the size of
the one that's in it.* It's probably enough smoothing with the original
size, I can't remember if it flickered when I bought it.* But clearly
the cap was overworked as it failed, so I'll fit something larger so it
lasts longer this time.

For the good ones, the only problem I can foresee with the external
smoother, is overloading the lamp's bridge rectifier, as it will
only be
conducting on two of the four diodes.

Should still be fine, most bridges in that situation are used
very conservitably and the diodes are rated for the initial
turn on surge current.

There's a current limiting resistor before them.

If I was to go ahead, I think I'd run one on the bench and check the
temperature of the diodes in normal operation.* If they're not very warm
then they won't mind double the current.

Don't those diodes handle surges anyway?* I mean a 3A diode will take
way more than that for a fraction of a second.* It's the heat that kills
them.* So why don't they just fit what they need to instead of bigger
ones?

trimmers , you need trimmers

An adjustable diode?* I'm quite sure you know nothing about what you're
talking.

who cares what you are quite sure of

On Thu, 20 Dec 2018 23:57:57 -0000, % wrote:

On 2018-12-20 4:16 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:51:48 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating. I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running. 3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try
replacing it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling). Loads of
them get bulged caps after a while, in particular a 3A PSU I ran 2A of
LEDs 24/7 from, failed in 1 year. It kept cutting out - I discovered
the bulk capacitor had dried out. Same happened (over a longer period)
with two monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not a
capacitor dropper. Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

And I think the LED failures are due to heat. I now run them with the
diffuser covers off to let them be cooler. I get more light out of them
too, and I think they look better when you can see all the dots.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space. "Corn on the cob LED lights"
they're called. I could literally fit a cap about 50 times the size of
the one that's in it. It's probably enough smoothing with the original
size, I can't remember if it flickered when I bought it. But clearly
the cap was overworked as it failed, so I'll fit something larger so it
lasts longer this time.

For the good ones, the only problem I can foresee with the external
smoother, is overloading the lamp's bridge rectifier, as it will
only be
conducting on two of the four diodes.

Should still be fine, most bridges in that situation are used
very conservitably and the diodes are rated for the initial
turn on surge current.

There's a current limiting resistor before them.

If I was to go ahead, I think I'd run one on the bench and check the
temperature of the diodes in normal operation. If they're not very warm
then they won't mind double the current.

Don't those diodes handle surges anyway? I mean a 3A diode will take
way more than that for a fraction of a second. It's the heat that kills
them. So why don't they just fit what they need to instead of bigger
ones?

trimmers , you need trimmers

An adjustable diode? I'm quite sure you know nothing about what you're
talking.

who cares what you are quite sure of

Please refrain from engaging in conversations about technical things that go over your head. Shall we talk about pretty flowers instead?

On Thu, 20 Dec 2018 23:57:18 -0000, % wrote:

On 2018-12-20 4:16 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:52:55 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:40:48 -0000, % wrote:

On 2018-12-20 2:38 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:04:01 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 17:13:52 -0000, trader_4
wrote:

On Thursday, December 20, 2018 at 12:07:40 PM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 16:25:22 -0000, trader_4

wrote:

On Thursday, December 20, 2018 at 7:29:53 AM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 11:57:01 -0000, whisky-dave
wrote:

On Wednesday, 19 December 2018 16:35:05 UTC, William Gothberg
wrote:
On Wed, 19 Dec 2018 16:21:41 -0000, Mark Lloyd

wrote:

On 12/19/18 6:01 AM, William Gothberg wrote:

[snip]

They probably are fairly crude. I know they flicker, for
example if I
use my cordless drill, the chuck appears to spin the
wrong
way
under the
LED lighting.
I remember seeing that with a washing machine (under
fluorescent
lights). As the tub was slowing down, the row of holes
around
the tub
would appear to reverse direction. Same thing with
(spoked)
wagon wheels
in movies.

It looks absolutely ridiculous with modern cars with LED
headlights in films. How hard can it be to put a smoothing
capacitor on the output of the power supply?

It's easy but that isn't the point. The most efficient way of
driving to make maximium power into the LED means yuo
have to
pulse the LED's. Using a capcitor to smooth out the DC is yet
another mode of inefficincy as it would get warm due to
current
flow. Indictors in series might be better but then you run
the
risk
of 'radio' interference.

Being inefficient would presumably make it impossible to get
enough
brightness out of LEDs that fit into the lamp holder. The LEDs
would
get too hot trying to give out enough brightness for a car
headlight.

However cars vary a lot, some are easy to detect flickering,
some
difficult, and some impossible (with the naked eye). Perhaps
they
just use a higher frequency?

Taillights are pretty bad on a lot of cars, as they dim the
brakelights by deliberately flickering them.

Either you have eyes that are way more sensitive to this or
you're in
a
country that uses different car lights than here in the USA.
There
are a lot of cars with LED lighting, headlights and rear
lights, and
I've never noticed this flickering, nor have I ever heard it
mentioned
before this thread. I haven't noticed flickering from any LED
lights
I've used either.

I can see flicker on a 60Hz CRT monitor, but not on a 90Hz one, so
that'll give you an idea on how good my eyes are.

Can you see flicker on tailliights if you scan your eyes across
the
scene?

Like I said, I haven't noticed it in the driving I've done. Nor
have I
heard anyone else mention it. Next time I come across a car
that has
LEDs I'll look more closely and see if I can see anything. If just
scanning reveals it, you;d think a lot of people would be noticing
it.
Scanning is a part of driving.

I'd estimate about 1 in 5 people can see it,

Its nothing like that high and we know that because nothing
like that many saw any flickering with fluorescent lights.

Er.... most people I know can see fluorescent flicker. It doesn't
annoy
most of them, but they can detect it. One in five people I know could
see 60Hz monitor flickering. And about the same can see car lights
flickering.

similar to how many can see flicker on a 60Hz CRT computer monitor.

Nothing even remotely like 1 in 5 can see that.

You must know some people with really ****ty eyesight. I noticed that
more people who were younger and/or didn't wear specs could see the
flicker.

Don't most cars have LEDs now? Or does your area have a lot of
older
cars? People (stupidly) around here seem to like cars that are no
more
than 10 years old. I don't think many cars after 2008 had bulbs.

Searching for "LED tail light flicker" without the quotes in google
produces 4.5 million results!

the same thing happens when i type your name and add the words gutless
idgit

Cite link.

you don't know how to type your name , come off it

Your name is not %

yes it is but that's off topic right now ,

No, it's part of a nym you made up.

right now we're talking about your admission you can't spell yours

I have not misspelt it. I used a fake one.

On Thu, 20 Dec 2018 23:56:14 -0000, % wrote:

On 2018-12-20 4:15 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:53:44 -0000, % wrote:

On 2018-12-20 2:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 21:25:45 -0000, % wrote:

On 2018-12-20 1:56 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 20:40:26 -0000, % wrote:

On 2018-12-20 1:30 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a
bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central heating. I'm looking inside the flickery lamp just now
(£15,
20W). Without undoing the glue holding the PSU onto the inside
of it,
all I can see is probably: the mains going through a large bipolar
cap,
a tiny resistor (to discharge it safely?), a bridge rectifier,
another
very large resister (to limit the LED current more accurately?),
then a
400V 4.7uF capacitor (which is bulged). A capacitor dropper with a
rectifier and smoothing capacitor after it? The one I made has no
smoothing cap, just mains to cap to resistor to bridge to LED.
Perhaps
this bulged cap is why I'm getting flicker, I'll try replacing it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap? I just bought a 12V 6A
SMPS
for £4.50. Designed for powering LEDs - but I've looked inside
it and
it's definitely a switched mode, not a capacitor dropper. Now this
flickery LED lamp I'm looking inside, it's about 20W, so 12V at
2A is
all that's required, it could have had an SMPS in it similar to the
one
I just described.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because when some LEDs fail short circuit (it has about 40 in
series),
the voltage coming from the PSU drops, to maintain the correct
current
for the remaining good LEDs.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.
Better
(as I only have a few crap ones) to stick a bigger smoothing cap
inside
those. For the good ones, the only problem I can foresee with the
external smoother, is overloading the lamp's bridge rectifier, as it
will only be conducting on two of the four diodes.

The cheap **** LED lamp I have that actually flashes at 100Hz
would
most
likely get much brighter and burn out, so I'd have to adjust that,
but the
others which only flicker 8% would just get 4% brighter.

you could use being 4 % brighter

That would make my IQ 140.

Was the above too difficult for you to discuss?

I Q's are the lamest oldest forgotten tests of them all ,

You're just jealous.

are you excited this is going to be how usenet is for you for the next
20 - 30 years

Be more specific.

no and start getting used to the idea that i don't do what you order

No point in you telling me something if you won't back it up.

say it to my face and we'll see about back up

I picture you as a geeky little wimp, and as such I am not afraid of you..

On Thu, 20 Dec 2018 23:55:34 -0000, % wrote:

On 2018-12-20 4:15 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 22:56:19 -0000, % wrote:

On 2018-12-20 3:48 p.m., William Gothberg wrote:
On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news If they're not very warm then they won't mind double the current.

Don't those diodes handle surges anyway?

Yeah, the surge rating is massive.

I mean a 3A diode will take way more than that for a fraction of a
second.

Yep.

It's the heat that kills them.

Not with bridges.

So why don't they just fit what they need to instead of bigger ones?

The bigger ones are the same price.

Its only when you got to the big ones
potted in a square aluminium thing with
a bolt hole in them that the price increases.

that's a trimmer

No, a trimmer is an adjustable resistor/capacitor/inductor:
https://en.wikipedia.org/wiki/Trimmer_(electronics)
Rod was talking about a very large diode.

no its not

Then you'd better correct Wikipedia.

"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating. I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running. 3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try replacing
it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling). Loads of
them
get bulged caps after a while, in particular a 3A PSU I ran 2A of LEDs
24/7 from, failed in 1 year. It kept cutting out - I discovered the
bulk
capacitor had dried out. Same happened (over a longer period) with two
monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not a
capacitor dropper. Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't
cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

Think its just the way leds fail naturally
with the higher powered lighting leds.

What's quite weird is with the decent strips I've got, the LEDs are wired
in pairs. Each pair is in parallel, then there are 20 such pairs in
series. When one single LED fails, I'd expect either it shorts and the
neighbouring one in the pair gets 0 volts, or it fails open circuit and
the neighbouring one gets double current and soon dies. But neither
happens. The neighbouring LED stays lit at the same brightness. Any idea
how this is possible? Could the dead LED still have the same current
going through it?

There are only 3 possibilitys.

The pairs arent actually wired in parallel, it only
looks like they are. This is the most likely.

When a led fails, it just stops emitting light but is still electrically
identical to before it failed. This is the least likely.

Or the leds don't actually vary in light they put out
visibly when the current doubles when one fails open.

And I think the LED failures are due to heat. I now run them with the
diffuser covers off to let them be cooler. I get more light out of them
too, and I think they look better when you can see all the dots.

I'm not rapt in that result with the led strips,
particularly with the reflection off glass etc.
I havent gotten around to mounting them
properly yet, mainly because for some
reason Bunnings doesn't stock the
extrusions to mount them in in the
very long 3-4M strips and those arent
feasible to buy online in those lengths.
Bit too crude imo to have a series of 1M ones.

I use something like these:
http://www.ebay.co.uk/itm/183429947350

Yeah, plenty of those, but my led strips
are 3-4M long and its pretty crude
having so many in a line. I would
prefer to just have the one 3-4M long.

They are available, but Bunnings doesn't stock them.

All I need is to screw a small clip every 2 feet into the ceiling,

I want mine much lower than that in the kitchen, just 2M or so from
the ground and I don't have overhead cupboards so want to run a
24mm RHS with the extrusion stuck to it with decent double sided
tape or pop riveted onto the RHS occasionally with no visible joins.

and have a plug with 240V at the end.

Yeah, that part is easy and what I want.

The strips plug into each other as many as I need, and just clip onto the
clips.

I'd prefer no visible joins but may well end up with that.

I do plan to have diffusers for those led
strips to fix the bright reflection of the
individual leds off the glass like the
front of the microwaves and wall oven
and windows.

Not sure why that would be a problem,

It isnt a problem, just doesn't look as
good as a continuous strip of light.

I quite like those reflections.

I'd prefer a continuous strip of light.

Same kinda idea as people liking bright halogen uplighters instead of a
more even light throughout the room.

Sure, but those don't have 50 or so dots of light.

If I wanted a more even light, I'd have to keep the diffusers on, but the
LEDs don't last so long.

Mine should do, 3 year warranty.

I guess I could dim them a bit instead.

I'd rather not.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space. "Corn on the cob LED lights"
they're
called.

I don't use those, use the Hue E27 bulbs.

I only have a couple, to fit into existing bayonet fittings,

I only have the one bayonet fitting that I don't use anymore.

but most of my house is now the strips I linked to above.

I mostly have E27 bulbs with a couple of 3-4M led strips in the
kitchen, one above each line of benches in the twin parallel set
of benches, one against the wall and the other an island bench.

Also means nothing hangs down from the ceiling

Yeah, I don't have any like that anywhere. Don't have a dining table.

and can get knocked. Plus since the light comes from the whole strip, no
shadows from myself when I'm trying to work on something.

Yeah, that's why I have the strips in the kitchen.

I could literally fit a cap about 50 times the size of the one that's in
it. It's probably enough smoothing with the original size, I can't
remember if it flickered when I bought it. But clearly the cap was
overworked as it failed, so I'll fit something larger so it lasts longer
this time.

Might well just be a low quality cap, not over worked.
Rectifier caps don't get overworked when not enough uF.

Maybe it's not a low ESR cap? Maybe the high temperature in there
shortens its life?

Yeah, quite likely tho I dunno if they bulge then.
I've had very few cap failures, just one in the Humax.

Same thing happens in my PSUs for monitors.

I havent had any of the LCD monitors fail.

Or more strictly had one of the Asus monitors fail under warranty,
the backlight failing so just got it fixed under warranty.

For the good ones, the only problem I can foresee with the external
smoother, is overloading the lamp's bridge rectifier, as it will only
be
conducting on two of the four diodes.

Should still be fine, most bridges in that situation are used
very conservitably and the diodes are rated for the initial
turn on surge current.

There's a current limiting resistor before them.

But the current rating would be vastly lower than the surge rating.

If I was to go ahead, I think I'd run one on the bench and check the
temperature of the diodes in normal operation.

They'll be fine at that current.

If they're not very warm then they won't mind double the current.

Don't those diodes handle surges anyway?

Yeah, the surge rating is massive.

I mean a 3A diode will take way more than that for a fraction of a
second.

Yep.

It's the heat that kills them.

Not with bridges.

So why don't they just fit what they need to instead of bigger ones?

The bigger ones are the same price.

Its only when you got to the big ones
potted in a square aluminium thing with
a bolt hole in them that the price increases.

"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 22:22:41 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 21:50:21 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:04:01 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 17:13:52 -0000, trader_4
wrote:

On Thursday, December 20, 2018 at 12:07:40 PM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 16:25:22 -0000, trader_4

wrote:

On Thursday, December 20, 2018 at 7:29:53 AM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 11:57:01 -0000, whisky-dave
wrote:

On Wednesday, 19 December 2018 16:35:05 UTC, William Gothberg
wrote:
On Wed, 19 Dec 2018 16:21:41 -0000, Mark Lloyd

wrote:

On 12/19/18 6:01 AM, William Gothberg wrote:

[snip]

They probably are fairly crude. I know they flicker, for
example if I
use my cordless drill, the chuck appears to spin the
wrong
way
under the
LED lighting.
I remember seeing that with a washing machine (under
fluorescent
lights). As the tub was slowing down, the row of holes
around
the tub
would appear to reverse direction. Same thing with
(spoked)
wagon wheels
in movies.

It looks absolutely ridiculous with modern cars with LED
headlights in films. How hard can it be to put a smoothing
capacitor on the output of the power supply?

It's easy but that isn't the point. The most efficient way of
driving to make maximium power into the LED means yuo have
to
pulse the LED's. Using a capcitor to smooth out the DC is yet
another mode of inefficincy as it would get warm due to
current
flow. Indictors in series might be better but then you run
the
risk
of 'radio' interference.

Being inefficient would presumably make it impossible to get
enough
brightness out of LEDs that fit into the lamp holder. The LEDs
would
get too hot trying to give out enough brightness for a car
headlight.

However cars vary a lot, some are easy to detect flickering,
some
difficult, and some impossible (with the naked eye). Perhaps
they
just use a higher frequency?

Taillights are pretty bad on a lot of cars, as they dim the
brakelights by deliberately flickering them.

Either you have eyes that are way more sensitive to this or
you're
in
a
country that uses different car lights than here in the USA.
There
are a lot of cars with LED lighting, headlights and rear lights,
and
I've never noticed this flickering, nor have I ever heard it
mentioned
before this thread. I haven't noticed flickering from any LED
lights
I've used either.

I can see flicker on a 60Hz CRT monitor, but not on a 90Hz one, so
that'll give you an idea on how good my eyes are.

Can you see flicker on tailliights if you scan your eyes across
the
scene?

Like I said, I haven't noticed it in the driving I've done. Nor
have
I
heard anyone else mention it. Next time I come across a car that
has
LEDs I'll look more closely and see if I can see anything. If just
scanning reveals it, you;d think a lot of people would be noticing
it.
Scanning is a part of driving.

I'd estimate about 1 in 5 people can see it,

Its nothing like that high and we know that because nothing
like that many saw any flickering with fluorescent lights.

Er.... most people I know can see fluorescent flicker. It doesn't
annoy
most of them, but they can detect it.

Don't believe it. I did have someone at work who could
see it and was asking about how to get it fixed but no
one else could see what she was talking about.

About 20 years ago I worked where everyone had a cheap 14" CRT monitor
running at 60Hz. They really bugged me with the flicker. When I asked
everyone about them, 80% couldn't see it, 10% said they were as annoyed
as
me, and 10% only saw it if they looked for it. For the 10% and the 10%,
I
bought some nice 90Hz Iiyama Vision Master Pro CRT monitors. They
absolutely loved them. The other 80% couldn't see what the fuss was
about, and most of them had specs or were older.

One in five people I know could see 60Hz monitor flickering.

Don't believe that either and I never had anyone complaining about it.

And about the same can see car lights flickering.

Don't believe that either and clearly the designers can't.

A quick google search shows many many people don't like car flicker.
Millions of results.

similar to how many can see flicker on a 60Hz CRT computer monitor.

Nothing even remotely like 1 in 5 can see that.

You must know some people with really ****ty eyesight.

I'm talking about everyone at work. NOT ONE could see that.

What age group were they in?

All of the, everything from those straight out
of school to those who were about to retire.
And the kids of many of them as well.

How odd. I can't believe Aussies have different eyes to Brits.

Yeah, I don't believe that either.

More sunlight in the room maybe?

That's certainly true of my main room but only in the daytime.

Having 90Hz CRTs to avoid flicker was quite common around the world, go
google it.

Don't need to, I know that but never saw the need for them.
OTOH I was using decent quality DEC VT100s, maybe the
phosphor was better chosen and that's why it wasn't a problem.

I noticed that more people who were younger and/or didn't wear specs
could see the flicker.

Don't buy that either. None of the kids could see it.

Even a colleague who never noticed it before when he looked at one of
the
new 90Hz monitors immediately remarked "that picture's really stable!"

Don't most cars have LEDs now? Or does your area have a lot of
older
cars? People (stupidly) around here seem to like cars that are no
more
than 10 years old. I don't think many cars after 2008 had bulbs.

Searching for "LED tail light flicker" without the quotes in google
produces 4.5 million results!

On Fri, 21 Dec 2018 01:06:46 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating. I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running. 3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try replacing
it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling). Loads of
them
get bulged caps after a while, in particular a 3A PSU I ran 2A of LEDs
24/7 from, failed in 1 year. It kept cutting out - I discovered the
bulk
capacitor had dried out. Same happened (over a longer period) with two
monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not a
capacitor dropper. Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't
cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

Think its just the way leds fail naturally
with the higher powered lighting leds.

What's quite weird is with the decent strips I've got, the LEDs are wired
in pairs. Each pair is in parallel, then there are 20 such pairs in
series. When one single LED fails, I'd expect either it shorts and the
neighbouring one in the pair gets 0 volts, or it fails open circuit and
the neighbouring one gets double current and soon dies. But neither
happens. The neighbouring LED stays lit at the same brightness. Any idea
how this is possible? Could the dead LED still have the same current
going through it?

There are only 3 possibilitys.

The pairs arent actually wired in parallel, it only
looks like they are. This is the most likely.

They're definitely in parallel. I've tested a broken strip in depth with a meter, and also looked at the circuit tracks. It's most definitely 2 LEDs in parallel, then 20 of those pairs in series. 70V DC is applied to the whole strip by the PSU. I've just looked at the voltage across the LEDs in the half busted strip pictured in the link below. Working pairs are 3.3V across each LED. Broken pairs are 2.6V across each LED. Pairs with one of the two lit are 3.6V per LED. No idea what that means!: https://www.dropbox.com/s/eml663rsoz...strip.jpg?dl=0

When a led fails, it just stops emitting light but is still electrically
identical to before it failed. This is the least likely.

I'd say it was the most likely, although from the above measurement in the photo, it looks like they stuill conduct, but a different amount, and the neighbour in the pair doesn't care that much. I think the neighbour is more likely to be the next to fail, so it might be getting a bit of a rough time.

Or the leds don't actually vary in light they put out
visibly when the current doubles when one fails open.

I don't believe that one, since they should end up failing very quickly at double power.

And I think the LED failures are due to heat. I now run them with the
diffuser covers off to let them be cooler. I get more light out of them
too, and I think they look better when you can see all the dots.

I'm not rapt in that result with the led strips,
particularly with the reflection off glass etc.
I havent gotten around to mounting them
properly yet, mainly because for some
reason Bunnings doesn't stock the
extrusions to mount them in in the
very long 3-4M strips and those arent
feasible to buy online in those lengths.
Bit too crude imo to have a series of 1M ones.

I use something like these:
http://www.ebay.co.uk/itm/183429947350

Yeah, plenty of those, but my led strips
are 3-4M long and its pretty crude
having so many in a line. I would
prefer to just have the one 3-4M long.

Mine plug together tightly so you barely notice the join. You can get them different lengths, but I just buy the 2 foot ones as I can arrange them more easily. My bedroom has one 2 foot strip. The bathroom has two, but seperate with a gap inbetween. The lounge has 4 singles and 4 joined together and a single corn shaped one, the kitchen has 5 joined together and singles under the wall cupboards, the garage has 8, 5 joined and 3 joined.

They are available, but Bunnings doesn't stock them.

Ever heard of Ebay?

All I need is to screw a small clip every 2 feet into the ceiling,

I want mine much lower than that in the kitchen, just 2M or so from
the ground

Er... I put my lights on the ceiling. Why would you want anything else?

and I don't have overhead cupboards so want to run a
24mm RHS with the extrusion stuck to it with decent double sided
tape or pop riveted onto the RHS occasionally with no visible joins.

What is an RHS?

and have a plug with 240V at the end.

Yeah, that part is easy and what I want.

The strips plug into each other as many as I need, and just clip onto the
clips.

I'd prefer no visible joins but may well end up with that.

I do plan to have diffusers for those led
strips to fix the bright reflection of the
individual leds off the glass like the
front of the microwaves and wall oven
and windows.

Not sure why that would be a problem,

It isnt a problem, just doesn't look as
good as a continuous strip of light.

I dunno, I think the dots look pretty.

I quite like those reflections.

I'd prefer a continuous strip of light.

Doesn't really bother me. I removed the diffusers only to make them run cooler and last longer.

Same kinda idea as people liking bright halogen uplighters instead of a
more even light throughout the room.

Sure, but those don't have 50 or so dots of light.

And each dot is MUCH dimmer than each halogen lamp.

If I wanted a more even light, I'd have to keep the diffusers on, but the
LEDs don't last so long.

Mine should do, 3 year warranty.

I think these have a 2 or 3 year warranty, they don't last that long with the diffusers on though. I prefer them to last for years instead of having to keep getting replacements.

I guess I could dim them a bit instead.

I'd rather not.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space. "Corn on the cob LED lights"
they're
called.

I don't use those, use the Hue E27 bulbs.

I only have a couple, to fit into existing bayonet fittings,

I only have the one bayonet fitting that I don't use anymore.

Yip, I've also almost got rid of traditional fittings. 3 CFLs left in the lounge though....

but most of my house is now the strips I linked to above.

I mostly have E27 bulbs with a couple of 3-4M led strips in the
kitchen, one above each line of benches in the twin parallel set
of benches, one against the wall and the other an island bench.

Also means nothing hangs down from the ceiling

Yeah, I don't have any like that anywhere. Don't have a dining table.

You said earlier you wanted lower lights in the kitchen?

and can get knocked. Plus since the light comes from the whole strip, no
shadows from myself when I'm trying to work on something.

Yeah, that's why I have the strips in the kitchen.

I like strips everywhere. A more even light.

I could literally fit a cap about 50 times the size of the one that's in
it. It's probably enough smoothing with the original size, I can't
remember if it flickered when I bought it. But clearly the cap was
overworked as it failed, so I'll fit something larger so it lasts longer
this time.

Might well just be a low quality cap, not over worked.
Rectifier caps don't get overworked when not enough uF.

Maybe it's not a low ESR cap? Maybe the high temperature in there
shortens its life?

Yeah, quite likely tho I dunno if they bulge then.
I've had very few cap failures, just one in the Humax.

I was there when the Dell PC motherboards all failed. Millions of dodgy Nichicon caps failed with a dodgy electrolyte across the world - called "the capacitor plague" - https://en.wikipedia.org/wiki/Capacitor_plague
150 PCs needed fixing under my command. Dell replaced some under warranty, I got motherboards off Ebay to replace older ones, then when those ran out I started desoldering the caps themselves. A bit fiddly but possible.

Same thing happens in my PSUs for monitors.

I havent had any of the LCD monitors fail.

The two that broke are quite old ones, with seperate PSUs, with 12V or 20V feeding into the actual monitor. Not sure why they chose to have seperate PSUs.

Or more strictly had one of the Asus monitors fail under warranty,
the backlight failing so just got it fixed under warranty.

Never had a backlight fail. Always the power caps (in TVs too), or once I had a chip go and one third of the screen produced random squares of colour. I gave it away to someone who uses the other two thirds for a Linux server.

On Fri, 21 Dec 2018 01:11:53 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 22:22:41 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:50:21 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:04:01 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 17:13:52 -0000, trader_4
wrote:

On Thursday, December 20, 2018 at 12:07:40 PM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 16:25:22 -0000, trader_4

wrote:

On Thursday, December 20, 2018 at 7:29:53 AM UTC-5, William
Gothberg
wrote:
On Thu, 20 Dec 2018 11:57:01 -0000, whisky-dave
wrote:

On Wednesday, 19 December 2018 16:35:05 UTC, William Gothberg
wrote:
On Wed, 19 Dec 2018 16:21:41 -0000, Mark Lloyd

wrote:

On 12/19/18 6:01 AM, William Gothberg wrote:

[snip]

They probably are fairly crude. I know they flicker, for
example if I
use my cordless drill, the chuck appears to spin the
wrong
way
under the
LED lighting.
I remember seeing that with a washing machine (under
fluorescent
lights). As the tub was slowing down, the row of holes
around
the tub
would appear to reverse direction. Same thing with
(spoked)
wagon wheels
in movies.

It looks absolutely ridiculous with modern cars with LED
headlights in films. How hard can it be to put a smoothing
capacitor on the output of the power supply?

It's easy but that isn't the point. The most efficient way of
driving to make maximium power into the LED means yuo have
to
pulse the LED's. Using a capcitor to smooth out the DC is yet
another mode of inefficincy as it would get warm due to
current
flow. Indictors in series might be better but then you run
the
risk
of 'radio' interference.

Being inefficient would presumably make it impossible to get
enough
brightness out of LEDs that fit into the lamp holder. The LEDs
would
get too hot trying to give out enough brightness for a car
headlight.

However cars vary a lot, some are easy to detect flickering,
some
difficult, and some impossible (with the naked eye). Perhaps
they
just use a higher frequency?

Taillights are pretty bad on a lot of cars, as they dim the
brakelights by deliberately flickering them.

Either you have eyes that are way more sensitive to this or
you're
in
a
country that uses different car lights than here in the USA.
There
are a lot of cars with LED lighting, headlights and rear lights,
and
I've never noticed this flickering, nor have I ever heard it
mentioned
before this thread. I haven't noticed flickering from any LED
lights
I've used either.

I can see flicker on a 60Hz CRT monitor, but not on a 90Hz one, so
that'll give you an idea on how good my eyes are.

Can you see flicker on tailliights if you scan your eyes across
the
scene?

Like I said, I haven't noticed it in the driving I've done. Nor
have
I
heard anyone else mention it. Next time I come across a car that
has
LEDs I'll look more closely and see if I can see anything. If just
scanning reveals it, you;d think a lot of people would be noticing
it.
Scanning is a part of driving.

I'd estimate about 1 in 5 people can see it,

Its nothing like that high and we know that because nothing
like that many saw any flickering with fluorescent lights.

Er.... most people I know can see fluorescent flicker. It doesn't
annoy
most of them, but they can detect it.

Don't believe it. I did have someone at work who could
see it and was asking about how to get it fixed but no
one else could see what she was talking about.

About 20 years ago I worked where everyone had a cheap 14" CRT monitor
running at 60Hz. They really bugged me with the flicker. When I asked
everyone about them, 80% couldn't see it, 10% said they were as annoyed
as
me, and 10% only saw it if they looked for it. For the 10% and the 10%,
I
bought some nice 90Hz Iiyama Vision Master Pro CRT monitors. They
absolutely loved them. The other 80% couldn't see what the fuss was
about, and most of them had specs or were older.

One in five people I know could see 60Hz monitor flickering.

Don't believe that either and I never had anyone complaining about it.

And about the same can see car lights flickering.

Don't believe that either and clearly the designers can't.

A quick google search shows many many people don't like car flicker.
Millions of results.

similar to how many can see flicker on a 60Hz CRT computer monitor.

Nothing even remotely like 1 in 5 can see that.

You must know some people with really ****ty eyesight.

I'm talking about everyone at work. NOT ONE could see that.

What age group were they in?

All of the, everything from those straight out
of school to those who were about to retire.
And the kids of many of them as well.

How odd. I can't believe Aussies have different eyes to Brits.

Yeah, I don't believe that either.

More sunlight in the room maybe?

That's certainly true of my main room but only in the daytime.

Having 90Hz CRTs to avoid flicker was quite common around the world, go
google it.

Don't need to, I know that but never saw the need for them.
OTOH I was using decent quality DEC VT100s, maybe the
phosphor was better chosen and that's why it wasn't a problem.

Yes the phosphor had a lot to do with it. Some phosphor was slower than others. Pairing a fast phosphor with a slow refresh rate made a lot of flicker.

I noticed that more people who were younger and/or didn't wear specs
could see the flicker.

Don't buy that either. None of the kids could see it.

Even a colleague who never noticed it before when he looked at one of
the
new 90Hz monitors immediately remarked "that picture's really stable!"

Don't most cars have LEDs now? Or does your area have a lot of
older
cars? People (stupidly) around here seem to like cars that are no
more
than 10 years old. I don't think many cars after 2008 had bulbs.

Searching for "LED tail light flicker" without the quotes in google
produces 4.5 million results!

"William Gothberg" "William wrote in message
news
On Fri, 21 Dec 2018 01:06:46 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a
bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating. I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all
I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after
it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor
to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running.
3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try
replacing
it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling). Loads of
them
get bulged caps after a while, in particular a 3A PSU I ran 2A of LEDs
24/7 from, failed in 1 year. It kept cutting out - I discovered the
bulk
capacitor had dried out. Same happened (over a longer period) with
two
monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the
flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not
a
capacitor dropper. Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't
cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

Think its just the way leds fail naturally
with the higher powered lighting leds.

What's quite weird is with the decent strips I've got, the LEDs are
wired
in pairs. Each pair is in parallel, then there are 20 such pairs in
series. When one single LED fails, I'd expect either it shorts and the
neighbouring one in the pair gets 0 volts, or it fails open circuit and
the neighbouring one gets double current and soon dies. But neither
happens. The neighbouring LED stays lit at the same brightness. Any
idea
how this is possible? Could the dead LED still have the same current
going through it?

There are only 3 possibilitys.

The pairs arent actually wired in parallel, it only
looks like they are. This is the most likely.

They're definitely in parallel. I've tested a broken strip in depth with
a meter, and also looked at the circuit tracks. It's most definitely 2
LEDs in parallel, then 20 of those pairs in series. 70V DC is applied to
the whole strip by the PSU. I've just looked at the voltage across the
LEDs in the half busted strip pictured in the link below. Working pairs
are 3.3V across each LED. Broken pairs are 2.6V across each LED.

So the third alternative is what is happening, the amount
of light isnt changing visibly when the current is doubled.

Pairs with one of the two lit are 3.6V per LED.

That doesn't fit with the first two sentences.

No idea what that means!:

That the amount of light doesn't change visibly when
the current doubles.

https://www.dropbox.com/s/eml663rsoz...strip.jpg?dl=0

Where are the pairs in that ? Two side by side are a pair wired in parallel
?

When a led fails, it just stops emitting light but is still electrically
identical to before it failed. This is the least likely.

I'd say it was the most likely, although from the above measurement in the
photo, it looks like they stuill conduct, but a different amount, and the
neighbour in the pair doesn't care that much.

Hard to say with the contradictory listing of the voltages.

I think the neighbour is more likely to be the next to fail, so it might
be getting a bit of a rough time.

That does look likely with the failure pattern in the pic.

Or the leds don't actually vary in light they put out
visibly when the current doubles when one fails open.

I don't believe that one, since they should end up failing very quickly at
double power.

Doesn't have to be very quickly.

They clearly do fail in pairs quite a bit.

And I think the LED failures are due to heat. I now run them with the
diffuser covers off to let them be cooler. I get more light out of
them
too, and I think they look better when you can see all the dots.

I'm not rapt in that result with the led strips,
particularly with the reflection off glass etc.
I havent gotten around to mounting them
properly yet, mainly because for some
reason Bunnings doesn't stock the
extrusions to mount them in in the
very long 3-4M strips and those arent
feasible to buy online in those lengths.
Bit too crude imo to have a series of 1M ones.

I use something like these:
http://www.ebay.co.uk/itm/183429947350

Yeah, plenty of those, but my led strips
are 3-4M long and its pretty crude
having so many in a line. I would
prefer to just have the one 3-4M long.

Mine plug together tightly so you barely notice the join. You can get
them different lengths, but I just buy the 2 foot ones as I can arrange
them more easily.

No use to me tho because they arent Hues.

My bedroom has one 2 foot strip. The bathroom has two, but seperate with
a gap inbetween. The lounge has 4 singles and 4 joined together and a
single corn shaped one, the kitchen has 5 joined together and singles
under the wall cupboards, the garage has 8, 5 joined and 3 joined.

They are available, but Bunnings doesn't stock them.

Ever heard of Ebay?

Corse I have but no one ships 3-4M long stuff by post or courier.
Bunnings have their trucks moving the long stuff.

All I need is to screw a small clip every 2 feet into the ceiling,

I want mine much lower than that in the kitchen, just 2M or so from
the ground

Er... I put my lights on the ceiling. Why would you want anything else?

and I don't have overhead cupboards so want to run a
24mm RHS with the extrusion stuck to it with decent double sided
tape or pop riveted onto the RHS occasionally with no visible joins.

What is an RHS?

Square metal tube. Rectangular Hollow Section.

and have a plug with 240V at the end.

Yeah, that part is easy and what I want.

The strips plug into each other as many as I need, and just clip onto
the
clips.

I'd prefer no visible joins but may well end up with that.

I do plan to have diffusers for those led
strips to fix the bright reflection of the
individual leds off the glass like the
front of the microwaves and wall oven
and windows.

Not sure why that would be a problem,

It isnt a problem, just doesn't look as
good as a continuous strip of light.

I dunno, I think the dots look pretty.

They look a bit odd when reflected off glass.

I quite like those reflections.

I'd prefer a continuous strip of light.

Doesn't really bother me. I removed the diffusers only to make them run
cooler and last longer.

Same kinda idea as people liking bright halogen uplighters instead of a
more even light throughout the room.

Sure, but those don't have 50 or so dots of light.

And each dot is MUCH dimmer than each halogen lamp.

If I wanted a more even light, I'd have to keep the diffusers on, but
the
LEDs don't last so long.

Mine should do, 3 year warranty.

I think these have a 2 or 3 year warranty, they don't last that long with
the diffusers on though. I prefer them to last for years instead of
having to keep getting replacements.

Yeah, **** that with the expensive Hues.

I guess I could dim them a bit instead.

I'd rather not.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space. "Corn on the cob LED lights"
they're
called.

I don't use those, use the Hue E27 bulbs.

I only have a couple, to fit into existing bayonet fittings,

I only have the one bayonet fitting that I don't use anymore.

Yip, I've also almost got rid of traditional fittings. 3 CFLs left in the
lounge though....

I only ever used one on the bed head light for the
much longer life than with incandescent bulbs.

Prior to the Hues I had PAR38 floods
and spots and 4' long tube fluoros.

but most of my house is now the strips I linked to above.

I mostly have E27 bulbs with a couple of 3-4M led strips in the
kitchen, one above each line of benches in the twin parallel set
of benches, one against the wall and the other an island bench.

Also means nothing hangs down from the ceiling

Yeah, I don't have any like that anywhere. Don't have a dining table.

You said earlier you wanted lower lights in the kitchen?

Yeah. but not hanging down from the ceiling. They
to on a 3-4M rhs between the walls at either end.

and can get knocked. Plus since the light comes from the whole strip,
no
shadows from myself when I'm trying to work on something.

Yeah, that's why I have the strips in the kitchen.

I like strips everywhere. A more even light.

Don't really need even light in the main room.

I could literally fit a cap about 50 times the size of the one that's
in
it. It's probably enough smoothing with the original size, I can't
remember if it flickered when I bought it. But clearly the cap was
overworked as it failed, so I'll fit something larger so it lasts
longer
this time.

Might well just be a low quality cap, not over worked.
Rectifier caps don't get overworked when not enough uF.

Maybe it's not a low ESR cap? Maybe the high temperature in there
shortens its life?

Yeah, quite likely tho I dunno if they bulge then.
I've had very few cap failures, just one in the Humax.

I was there when the Dell PC motherboards all failed.

Never had that with any motherboards.

Millions of dodgy Nichicon caps failed with a dodgy electrolyte across the
world - called "the capacitor plague" -

It wasn't dodgy electrolyte, dodgy caps.

https://en.wikipedia.org/wiki/Capacitor_plague
150 PCs needed fixing under my command. Dell replaced some under
warranty, I got motherboards off Ebay to replace older ones, then when
those ran out I started desoldering the caps themselves. A bit fiddly but
possible.

Yeah, I replaced the one in the humax. Bit of a tight fit.

Same thing happens in my PSUs for monitors.

I havent had any of the LCD monitors fail.

The two that broke are quite old ones, with seperate PSUs, with 12V or 20V
feeding into the actual monitor. Not sure why they chose to have seperate
PSUs.

Never had any like that.

Or more strictly had one of the Asus monitors fail under warranty,
the backlight failing so just got it fixed under warranty.

Never had a backlight fail. Always the power caps (in TVs too), or once I
had a chip go and one third of the screen produced random squares of
colour. I gave it away to someone who uses the other two thirds for a
Linux server.

On Fri, 21 Dec 2018 12:11:53 +1100, cantankerous trolling geezer Rot Speed,
the auto-contradicting senile sociopath, blabbered, again:

FLUSH another 213 lines of the two prize idiots' sick ****

....and much better air in here again!

--
about senile Rot Speed:
"This is like having a conversation with someone with brain damage."
MID:

On Fri, 21 Dec 2018 12:06:46 +1100, cantankerous trolling geezer Rot Speed,
the auto-contradicting senile sociopath, blabbered, again:

FLUSH 323 lines of the two subnormal idiots' endless sick troll****

--
The Natural Philosopher about senile Rot:
"Rod speed is not a Brexiteer. He is an Australian troll and arsehole."
Message-ID:

....and much better air in here again!

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we shippe the likes of you out of the British Isles. Perhaps stupidity
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Message-ID:

On Fri, 21 Dec 2018 04:11:46 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Fri, 21 Dec 2018 01:06:46 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a
bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating. I'm looking inside the flickery lamp just now (£15, 20W).
Without undoing the glue holding the PSU onto the inside of it, all
I
can
see is probably: the mains going through a large bipolar cap, a tiny
resistor (to discharge it safely?), a bridge rectifier, another very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after
it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor
to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was running.
3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try
replacing
it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water pump.

It was sold for LEDs, presumably it will run anything provided I don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling). Loads of
them
get bulged caps after a while, in particular a 3A PSU I ran 2A of LEDs
24/7 from, failed in 1 year. It kept cutting out - I discovered the
bulk
capacitor had dried out. Same happened (over a longer period) with
two
monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the
flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode, not
a
capacitor dropper. Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't
cost that much.

I'm now looking inside one of the better LED lamps (the non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of LED
designed to do this?

Think its just the way leds fail naturally
with the higher powered lighting leds.

What's quite weird is with the decent strips I've got, the LEDs are
wired
in pairs. Each pair is in parallel, then there are 20 such pairs in
series. When one single LED fails, I'd expect either it shorts and the
neighbouring one in the pair gets 0 volts, or it fails open circuit and
the neighbouring one gets double current and soon dies. But neither
happens. The neighbouring LED stays lit at the same brightness. Any
idea
how this is possible? Could the dead LED still have the same current
going through it?

There are only 3 possibilitys.

The pairs arent actually wired in parallel, it only
looks like they are. This is the most likely.

They're definitely in parallel. I've tested a broken strip in depth with
a meter, and also looked at the circuit tracks. It's most definitely 2
LEDs in parallel, then 20 of those pairs in series. 70V DC is applied to
the whole strip by the PSU. I've just looked at the voltage across the
LEDs in the half busted strip pictured in the link below. Working pairs
are 3.3V across each LED. Broken pairs are 2.6V across each LED.

So the third alternative is what is happening, the amount
of light isnt changing visibly when the current is doubled.

Not my experience with any type of LED, higher current or a very slightly higher voltage usually ****s them completely.

Pairs with one of the two lit are 3.6V per LED.

That doesn't fit with the first two sentences.

Why doesn't it? The voltage rises slightly when one of the pair fails. More voltage needed to pass the same current through that pair, as the dead one is providing a greater resistance.

No idea what that means!:

That the amount of light doesn't change visibly when
the current doubles.

https://www.dropbox.com/s/eml663rsoz...strip.jpg?dl=0

Where are the pairs in that ? Two side by side are a pair wired in parallel
?

They're not physically side by side. Physically they're in a single line of 40. But they're wired in pairs, the first two, the second two, etc..

When a led fails, it just stops emitting light but is still electrically
identical to before it failed. This is the least likely.

I'd say it was the most likely, although from the above measurement in the
photo, it looks like they stuill conduct, but a different amount, and the
neighbour in the pair doesn't care that much.

Hard to say with the contradictory listing of the voltages.

That's confused me. If both in a pair break, they seem to conduct MORE easily, as the voltage lowers. If one breaks, it seems to conduct LESS easily, as a higher voltage is required to make the other take the same current. The only conclusion I can come to is they're failing differently depending on if they're the first or second to go in a pair. Measuring all of them - each pair obviously had the same voltage across each (I've confirmed by looking closely, they're definitely 2 LEDs in parallel, then another 2, then another 2, etc, with each pair in series with the next pair and so on, to create a string of 24 x (2 paralleled LEDs) in series.:
https://www.dropbox.com/s/1ruivl8arz...tages.jpg?dl=0
Perhaps what happens is, one fails open circuit in a pair, and the other takes slightly more voltage to conduct double the current. Eventually it wears out as it's being pushed harder, and fails in a different way, conducting.
I've also noticed that pressing lightly on the LEDs can make a broken one light up temporarily - must be something coming loose inside them.

I think the neighbour is more likely to be the next to fail, so it might
be getting a bit of a rough time.

That does look likely with the failure pattern in the pic.

Or the leds don't actually vary in light they put out
visibly when the current doubles when one fails open.

I don't believe that one, since they should end up failing very quickly at
double power.

Doesn't have to be very quickly.

I'm used to LEDs getting very very upset with even a minor change in voltage/current. Maybe ultra bright ones are less sensitive?

They clearly do fail in pairs quite a bit.

Agreed, but not as quick as I would have thought.

And I think the LED failures are due to heat. I now run them with the
diffuser covers off to let them be cooler. I get more light out of
them
too, and I think they look better when you can see all the dots.

I'm not rapt in that result with the led strips,
particularly with the reflection off glass etc.
I havent gotten around to mounting them
properly yet, mainly because for some
reason Bunnings doesn't stock the
extrusions to mount them in in the
very long 3-4M strips and those arent
feasible to buy online in those lengths.
Bit too crude imo to have a series of 1M ones.

I use something like these:
http://www.ebay.co.uk/itm/183429947350

Yeah, plenty of those, but my led strips
are 3-4M long and its pretty crude
having so many in a line. I would
prefer to just have the one 3-4M long.

Mine plug together tightly so you barely notice the join. You can get
them different lengths, but I just buy the 2 foot ones as I can arrange
them more easily.

No use to me tho because they arent Hues.

Not sure what your fascination is with hues. Do you like different colours depending on your mood? Or are you doing something fancy with them for automation? If it's the latter, I find a simple PIR detector in each room is all you need. If I or a pet is moving in the room, the light comes on for a set time, then goes off if it hasn't seen any movement. In rooms such as the lounge where I'm likely to be sat still for long periods watching TV, I set it to 15 minutes. For the bedroom it's 20 seconds so I don't have to wait for darkness to get to sleep.

My bedroom has one 2 foot strip. The bathroom has two, but seperate with
a gap inbetween. The lounge has 4 singles and 4 joined together and a
single corn shaped one, the kitchen has 5 joined together and singles
under the wall cupboards, the garage has 8, 5 joined and 3 joined.

They are available, but Bunnings doesn't stock them.

Ever heard of Ebay?

Corse I have but no one ships 3-4M long stuff by post or courier.
Bunnings have their trucks moving the long stuff.

Something wrong with Aussie couriers then, I just bought thirty enormous panels of welded mesh for some pet caging. They came by courier, on a large truck.

All I need is to screw a small clip every 2 feet into the ceiling,

I want mine much lower than that in the kitchen, just 2M or so from
the ground

Er... I put my lights on the ceiling. Why would you want anything else?

and I don't have overhead cupboards so want to run a
24mm RHS with the extrusion stuck to it with decent double sided
tape or pop riveted onto the RHS occasionally with no visible joins.

What is an RHS?

Square metal tube. Rectangular Hollow Section.

And this RHS runs along your ceiling? Or is suspended lower than your very high ceiling? In that case I'd just screw the clips into the RHS, and attach them as I already do. If you don't want to screw into the RHS, just glue or tape the 2 foot strips I use straight onto the RHS (the back of them is perfectly flat).

and have a plug with 240V at the end.

Yeah, that part is easy and what I want.

The strips plug into each other as many as I need, and just clip onto
the
clips.

I'd prefer no visible joins but may well end up with that.

I do plan to have diffusers for those led
strips to fix the bright reflection of the
individual leds off the glass like the
front of the microwaves and wall oven
and windows.

Not sure why that would be a problem,

It isnt a problem, just doesn't look as
good as a continuous strip of light.

I dunno, I think the dots look pretty.

They look a bit odd when reflected off glass.

No, they just look like dots of light, same as they do looking at them directly. I'd find that no more annoying than a diffused light reflecting off the glass.

I quite like those reflections.

I'd prefer a continuous strip of light.

Doesn't really bother me. I removed the diffusers only to make them run
cooler and last longer.

Same kinda idea as people liking bright halogen uplighters instead of a
more even light throughout the room.

Sure, but those don't have 50 or so dots of light.

And each dot is MUCH dimmer than each halogen lamp.

If I wanted a more even light, I'd have to keep the diffusers on, but
the
LEDs don't last so long.

Mine should do, 3 year warranty.

I think these have a 2 or 3 year warranty, they don't last that long with
the diffusers on though. I prefer them to last for years instead of
having to keep getting replacements.

Yeah, **** that with the expensive Hues.

**** what? Having to buy more? If you removed the covers they'd last longer.

I guess I could dim them a bit instead.

I'd rather not.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space. "Corn on the cob LED lights"
they're
called.

I don't use those, use the Hue E27 bulbs.

I only have a couple, to fit into existing bayonet fittings,

I only have the one bayonet fitting that I don't use anymore.

Yip, I've also almost got rid of traditional fittings. 3 CFLs left in the
lounge though....

I only ever used one on the bed head light for the
much longer life than with incandescent bulbs.

Prior to the Hues I had PAR38 floods
and spots and 4' long tube fluoros.

Incandescents use way too much electricity (5 times a CFL). When CFLs were invented I changed all the incandescents for those as the incandescents failed.

but most of my house is now the strips I linked to above.

I mostly have E27 bulbs with a couple of 3-4M led strips in the
kitchen, one above each line of benches in the twin parallel set
of benches, one against the wall and the other an island bench.

Also means nothing hangs down from the ceiling

Yeah, I don't have any like that anywhere. Don't have a dining table..

You said earlier you wanted lower lights in the kitchen?

Yeah. but not hanging down from the ceiling. They
to on a 3-4M rhs between the walls at either end.

Why do you want the lights lower than the ceiling?

and can get knocked. Plus since the light comes from the whole strip,
no
shadows from myself when I'm trying to work on something.

Yeah, that's why I have the strips in the kitchen.

I like strips everywhere. A more even light.

Don't really need even light in the main room.

It's much better, you never find yourself trying to see something in your own shadow.

I could literally fit a cap about 50 times the size of the one that's
in
it. It's probably enough smoothing with the original size, I can't
remember if it flickered when I bought it. But clearly the cap was
overworked as it failed, so I'll fit something larger so it lasts
longer
this time.

Might well just be a low quality cap, not over worked.
Rectifier caps don't get overworked when not enough uF.

Maybe it's not a low ESR cap? Maybe the high temperature in there
shortens its life?

Yeah, quite likely tho I dunno if they bulge then.
I've had very few cap failures, just one in the Humax.

I was there when the Dell PC motherboards all failed.

Never had that with any motherboards.

It was faulty batches from certain cap manufacturers, that ended up in batches of computers (mainly Dell). We had 150 computers all go that were purchased at a similar time.

Millions of dodgy Nichicon caps failed with a dodgy electrolyte across the
world - called "the capacitor plague" -

It wasn't dodgy electrolyte, dodgy caps.

Wikipedia says the electrolyte was made wrong: "faulty electrolyte composition that caused corrosion accompanied by gas generation"

https://en.wikipedia.org/wiki/Capacitor_plague
150 PCs needed fixing under my command. Dell replaced some under
warranty, I got motherboards off Ebay to replace older ones, then when
those ran out I started desoldering the caps themselves. A bit fiddly but
possible.

Yeah, I replaced the one in the humax. Bit of a tight fit.

I thought Humax was a decent make. Did you replace it like for like or put a bigger one in?

Same thing happens in my PSUs for monitors.

I havent had any of the LCD monitors fail.

The two that broke are quite old ones, with seperate PSUs, with 12V or 20V
feeding into the actual monitor. Not sure why they chose to have seperate
PSUs.

Never had any like that.

They're the only two I've had like that. Mind you I've seen caps fail the same way inside my parents' and my neighbours' TVs, so I can't really blame them being in a seperate box.

Or more strictly had one of the Asus monitors fail under warranty,
the backlight failing so just got it fixed under warranty.

Never had a backlight fail. Always the power caps (in TVs too), or once I
had a chip go and one third of the screen produced random squares of
colour. I gave it away to someone who uses the other two thirds for a
Linux server.

On Fri, 21 Dec 2018 13:58:10 -0000, William Gothberg "William wrote:

On Fri, 21 Dec 2018 04:11:46 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Fri, 21 Dec 2018 01:06:46 -0000, Rod Speed
wrote:

When a led fails, it just stops emitting light but is still electrically
identical to before it failed. This is the least likely.

I'd say it was the most likely, although from the above measurement in the
photo, it looks like they stuill conduct, but a different amount, and the
neighbour in the pair doesn't care that much.

Hard to say with the contradictory listing of the voltages.

That's confused me. If both in a pair break, they seem to conduct MORE easily, as the voltage lowers. If one breaks, it seems to conduct LESS easily, as a higher voltage is required to make the other take the same current. The only conclusion I can come to is they're failing differently depending on if they're the first or second to go in a pair. Measuring all of them - each pair obviously had the same voltage across each (I've confirmed by looking closely, they're definitely 2 LEDs in parallel, then another 2, then another 2, etc, with each pair in series with the next pair and so on, to create a string of 24 x (2 paralleled LEDs) in series.:
https://www.dropbox.com/s/1ruivl8arz...tages.jpg?dl=0
Perhaps what happens is, one fails open circuit in a pair, and the other takes slightly more voltage to conduct double the current. Eventually it wears out as it's being pushed harder, and fails in a different way, conducting.
I've also noticed that pressing lightly on the LEDs can make a broken one light up temporarily - must be something coming loose inside them.

Forgot to add, I tested shorting out a quarter of the LEDs, and the voltage at the ends drops, so it's definitely constant current.

On Fri, 21 Dec 2018 14:12:52 -0000, William Gothberg "William wrote:

On Fri, 21 Dec 2018 13:58:10 -0000, William Gothberg "William wrote:

On Fri, 21 Dec 2018 04:11:46 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news On Fri, 21 Dec 2018 01:06:46 -0000, Rod Speed
wrote:

When a led fails, it just stops emitting light but is still electrically
identical to before it failed. This is the least likely.

I'd say it was the most likely, although from the above measurement in the
photo, it looks like they stuill conduct, but a different amount, and the
neighbour in the pair doesn't care that much.

Hard to say with the contradictory listing of the voltages.

That's confused me. If both in a pair break, they seem to conduct MORE easily, as the voltage lowers. If one breaks, it seems to conduct LESS easily, as a higher voltage is required to make the other take the same current. The only conclusion I can come to is they're failing differently depending on if they're the first or second to go in a pair. Measuring all of them - each pair obviously had the same voltage across each (I've confirmed by looking closely, they're definitely 2 LEDs in parallel, then another 2, then another 2, etc, with each pair in series with the next pair and so on, to create a string of 24 x (2 paralleled LEDs) in series.:
https://www.dropbox.com/s/1ruivl8arz...tages.jpg?dl=0
Perhaps what happens is, one fails open circuit in a pair, and the other takes slightly more voltage to conduct double the current. Eventually it wears out as it's being pushed harder, and fails in a different way, conducting.
I've also noticed that pressing lightly on the LEDs can make a broken one light up temporarily - must be something coming loose inside them.

Forgot to add, I tested shorting out a quarter of the LEDs, and the voltage at the ends drops, so it's definitely constant current.

Curiouser and curiouser. The PSU from a completely broken strip is this one exactly (I can see the model number on it):
https://www.aliexpress.com/item/10pc...361438466.html
That's an 18W driver, giving out a constant current of 240-300mA (why the range?)
But it's out of a 9W strip of LEDs, which failed rather rapidly once a few LEDs had gone. I think it was giving them too much current, they put in the wrong supply. The one I photographed which is not killing the remaining LEDs has a different supply in it (larger and more complicated) even though it's the same strip of LEDs in the same case bought from the same supplier (at a different time).

On Thu, 20 Dec 2018 19:25:49 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 04:27:41 -0000, Clare Snyder
wrote:

On Wed, 19 Dec 2018 16:39:50 -0000, "William Gothberg" "William
wrote:

On Wed, 19 Dec 2018 16:34:11 -0000, whisky-dave
wrote:

On Wednesday, 19 December 2018 16:21:43 UTC, Mark Lloyd wrote:
On 12/19/18 6:01 AM, William Gothberg wrote:

[snip]

They probably are fairly crude. I know they flicker, for example if
I
use my cordless drill, the chuck appears to spin the wrong way under
the
LED lighting.
I remember seeing that with a washing machine (under fluorescent
lights). As the tub was slowing down, the row of holes around the tub
would appear to reverse direction. Same thing with (spoked) wagon
wheels
in movies.

You can also observe such things using a smartphone that has a high FPS
rate for recodring movie.
I can see the labs lights flicker when I film at 240FPS standard 60
and everything seems fine.

Everybody seems to constantly cut corners. Lights should just be on, no
flicker at all. ****ing annoying if you have decent eyesight, I can see
the flicker from almost everyone's LED tail lights.


This is sounding more and more like our "engineer friend" who needs
to do his own tire repairs and alignments and clutch repairs.

Don't know who you're referring to, but what's wrong with striving for
perfection?

It increases costs for everyone who isnt a freak.

There's perfection and there's perfection. You for example like LEDs you can control the colour of, nothing wrong with that. But OCD folk take things too far, like washing their car every day because of two specks of dust.

On Thu, 20 Dec 2018 19:24:19 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 13:19:55 -0000, whisky-dave
wrote:

On Thursday, 20 December 2018 13:00:02 UTC, William Gothberg wrote:
On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a bridge
rectifier and a huge capacitor,

No they'd probbaly blow up, don;t forget a bridge recifir would produce a
voltage of at leat 330V and the power dissapated by each LED would also
increase .

I thought about that, and the cheapest one, which seems to be just a
bridge rectifier straight to the LEDs, would make them 65% brighter. But
the others should only get 4% brighter. A switched mode supply fed by DC
at the peak voltage of the mains, would still have its bulk capacitor at
about the same voltage. It's already doing what I'm suggesting I do
externally. They're rated at 85-260V, so I assume they're switched mode.

Not necessarily. Its quite possible to do a capacitor dropper powering
a current regulator that way. Have a look a Big Clive's teardowns.

I've looked inside and I now know they are SMPS.

On Thu, 20 Dec 2018 18:55:13 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 08:19:58 -0000, gregz wrote:

Clare Snyder wrote:
On Wed, 19 Dec 2018 19:34:57 -0000, "William Gothberg" "William
wrote:

On Wed, 19 Dec 2018 18:03:19 -0000, Clark W. Griswold
wrote:

On 12/19/2018 11:36 AM, William Gothberg wrote:
On Wed, 19 Dec 2018 16:18:29 -0000, Mark Lloyd
wrote:

On 12/19/18 5:23 AM, William Gothberg wrote:
Do switch mode power supplies flicker in time with mains?
Specifically
LED power supplies in commercially available domestic lamps. By in
time, I don't mean at the same 50/60Hz, but anchored to it. I.e. if
you
have several such lamps each with their own built in supply, will
they
all flicker in time, using the mains frequency to keep them in
time, or
will they be random, making the room overall not flicker due to
them all
being random? And is there any way I can test this? I tried
taking
photos of them, but my camera only goes as fast as 1/2000th of a
second,
which shows all the lights at the same brightness each time, I
suspect
the flicker is above 2000Hz.

I once had an audio amplifier with a solar cell rather than a
microphone
for the input transducer. This made it possible to listen to light.
The
sun is steady, incandescent lights (AC powered) hum.

That was 40 years ago. Maybe something like that would work today.

The trouble is I want to compare 2kHz+ from one light with 2kHz+ from
a neighbouring light and see if they're in sync.

Maybe use a dual trace oscilloscope?

Haven't got one unfortunately.

Since this landed in alt.home.repair, I gotta ask. Do you have
single-phase or two-phase?

Single. I'm in the UK.
so 50 Htz - you can almost see an incandescent flicker at that
frequency (at 25 you could)

(also rules out the previously mentioned "engineer friend")

Lights flicker at twice the frequency, once for positive cycle, and once
for negative cycle. LEDs only once unles using a bridge rectifier, or
steady on using DC. Even though blinking they look normal straight on, my
brain says something is wrong

Some brains (or eyes) seem to be faster than others. I can easily (and
annoyingly) see flicker on CRT monitors below 90Hz, others don't even see
the 50 or 60Hz ones. I can see flicker on 80% of car LED lights, others
don't see any. Designers really ought to account for those of us with
better eyesight.

No point in doing that.

There is when half the population is capable of seeing it. Why only sell things suitable for those with ****ty eyesight? If you can't see the flicker that I can, then your eyes aren't as good as mine.

On Thu, 20 Dec 2018 18:50:23 -0000, Rod Speed wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to the
camera.

Good idea.

I just tried it with the best lamps I have, which show a slight variation
in brightness at exactly 100Hz, which must be seeping through from the
mains. However the LEDs never go off, they just change brightness by 8%.

With the worst lamp, same 100Hz, but they actually go right on and off,
with a duty cycle of 0.6.

Am I right in thinking these aren't SMPS at all?

Yep. those will have simple capacitance droppers.

Correct, although there is a failed smoothing cap on the end, which I still have to get round to replacing. I've got as far as finding something that will fit in the garage....

"William Gothberg" "William wrote in message
news
On Fri, 21 Dec 2018 04:11:46 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news
On Fri, 21 Dec 2018 01:06:46 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news On Thu, 20 Dec 2018 22:14:31 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 21:35:49 -0000, Rod Speed

wrote:



"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 19:11:36 -0000, Rod Speed

wrote:

"William Gothberg" "William wrote in
message
news On Thu, 20 Dec 2018 09:36:02 -0000, Jon Fairbairn
wrote:

"William Gothberg" "William writes:
Agreed. All I can detect (with my digital camera) is that
one brand of LED light I have flickers about 5 times less
(not sure if it's smother or faster) than the others.

Try a longer exposure and move the light rapidly relative to
the
camera.

I wonder, if I fed the lamps with mains voltage DC, simply a
bridge
rectifier and a huge capacitor, they'd reduce their flicker.

Wont work at all if they use capacitor droppers and

I made a few of those to power LEDs to indicate the function of my
central
heating. I'm looking inside the flickery lamp just now (£15,
20W).
Without undoing the glue holding the PSU onto the inside of it,
all
I
can
see is probably: the mains going through a large bipolar cap, a
tiny
resistor (to discharge it safely?), a bridge rectifier, another
very
large
resister (to limit the LED current more accurately?), then a 400V
4.7uF
capacitor (which is bulged).

A capacitor dropper with a rectifier and smoothing capacitor after
it?

Yep, that's what it is.

The one I made has no smoothing cap, just mains to cap to resistor
to
bridge to LED.

Yeah, not need for one if you don't mind the 100Hz flicker.

It was just indicator LEDs to tell me what water circuit was
running.
3
zones from the one boiler switched with valves.

Perhaps this bulged cap is why I'm getting flicker, I'll try
replacing
it
tomorrow.

they very likely do because those are the only cheap
droppers for dropping such a large voltage.

Aren't miniature SMPS units pretty cheap?

Not as cheap as the cap and the bridge rectifier.

I just bought a 12V 6A SMPS for £4.50.

Yeah, I did too.

Designed for powering LEDs

Mine will run anything 12V. I currently use it to power a water
pump.

It was sold for LEDs, presumably it will run anything provided I
don't
exceed the 6A.

However I've noticed they scrimp on the caps (or cooling). Loads of
them
get bulged caps after a while, in particular a 3A PSU I ran 2A of
LEDs
24/7 from, failed in 1 year. It kept cutting out - I discovered the
bulk
capacitor had dried out. Same happened (over a longer period) with
two
monitor PSUs.

The LEDs I use are all Hues and have their
own power supply with the led strips.

The one I mentioned above was for an insectocuter, I removed the
flours
and ballast and fitted strips of UV LEDs instead.

- but I've looked inside it and it's definitely a switched mode,
not
a
capacitor dropper. Now this flickery LED lamp I'm looking inside,
it's
about 20W, so 12V at 2A is all that's required, it could have had
an
SMPS
in it similar to the one I just described.

Yeah, but the cap and bridge are cheaper.

Well I've got 9W £4 strips with a switched mode PSU in them, so they
can't
cost that much.

I'm now looking inside one of the better LED lamps (the
non-flickery
model). It has a basic SMPS inside it. They're 9W and £4 each
for
the
whole lamp. I'm sure it's more than just a standard SMPS though,
because
when some LEDs fail short circuit (it has about 40 in series), the
voltage
coming from the PSU drops, to maintain the correct current for the
remaining good LEDs.

Yeah, its best to drive leds in constant current mode.

I'm surprised that the LEDs always fail short circuit, new type of
LED
designed to do this?

Think its just the way leds fail naturally
with the higher powered lighting leds.

What's quite weird is with the decent strips I've got, the LEDs are
wired
in pairs. Each pair is in parallel, then there are 20 such pairs in
series. When one single LED fails, I'd expect either it shorts and
the
neighbouring one in the pair gets 0 volts, or it fails open circuit
and
the neighbouring one gets double current and soon dies. But neither
happens. The neighbouring LED stays lit at the same brightness. Any
idea
how this is possible? Could the dead LED still have the same current
going through it?

There are only 3 possibilitys.

The pairs arent actually wired in parallel, it only
looks like they are. This is the most likely.

They're definitely in parallel. I've tested a broken strip in depth
with
a meter, and also looked at the circuit tracks. It's most definitely 2
LEDs in parallel, then 20 of those pairs in series. 70V DC is applied
to
the whole strip by the PSU. I've just looked at the voltage across the
LEDs in the half busted strip pictured in the link below. Working pairs
are 3.3V across each LED. Broken pairs are 2.6V across each LED.

So the third alternative is what is happening, the amount
of light isnt changing visibly when the current is doubled.

Not my experience with any type of LED, higher current or a very slightly
higher voltage usually ****s them completely.

No other viable explanation for the voltages
you said you are seeing unless you mangled
the statement completely.

Pairs with one of the two lit are 3.6V per LED.

That doesn't fit with the first two sentences.

Why doesn't it?

OK, on further reading that was my brain fart.

So cancel my comment about the light level
change not being noticeable with double
the current, it's a lot less than double the
current, but clearly the light level doesn't
change even with a current change.

The voltage rises slightly when one of the pair fails. More voltage
needed to pass the same current through that pair, as the dead one is
providing a greater resistance.

No idea what that means!:

That the amount of light doesn't change visibly when
the current doubles.

https://www.dropbox.com/s/eml663rsoz...strip.jpg?dl=0

Where are the pairs in that ? Two side by side are a pair wired in
parallel ?

They're not physically side by side. Physically they're in a single line
of 40.

Yeah, I meant adjacent.

But they're wired in pairs, the first two, the second two, etc.

Yeah, that's what I meant.

When a led fails, it just stops emitting light but is still
electrically
identical to before it failed. This is the least likely.

I'd say it was the most likely, although from the above measurement in
the
photo, it looks like they stuill conduct, but a different amount, and
the
neighbour in the pair doesn't care that much.

Hard to say with the contradictory listing of the voltages.

That's confused me.

Yeah, my brain fart.

If both in a pair break, they seem to conduct MORE easily, as the voltage
lowers.

Yes, the resistance drops. They don't fail short
circuit, but certainly the resistance does drop.

If one breaks, it seems to conduct LESS easily, as a higher voltage is
required to make the other take the same current. The only conclusion I
can come to is they're failing differently depending on if they're the
first or second to go in a pair.

Measuring all of them - each pair obviously had the same voltage across
each

(I've confirmed by looking closely, they're definitely 2 LEDs in parallel,
then another 2, then another 2, etc, with each pair in series with the
next pair and so on, to create a string of 24 x (2 paralleled LEDs) in
series.:
https://www.dropbox.com/s/1ruivl8arz...tages.jpg?dl=0

That's quite a bit of variation with the pairs with both still working.

It would be interesting to know what the voltage across
a pair was before one failed. Maybe the ones that failed
were the lowest resistance leds that failed first because
the current was too much for those ones.

Perhaps what happens is, one fails open circuit in a pair, and the other
takes slightly more voltage to conduct double the current. Eventually it
wears out as it's being pushed harder, and fails in a different way,
conducting.

Unlikely to fail a different way.

I've also noticed that pressing lightly on the LEDs can make a broken one
light up temporarily - must be something coming loose inside them.

Yeah, but clearly not a simple open circuit.

I think the neighbour is more likely to be the next to fail, so it might
be getting a bit of a rough time.

That does look likely with the failure pattern in the pic.

Or the leds don't actually vary in light they put out
visibly when the current doubles when one fails open.

I don't believe that one, since they should end up failing very quickly
at
double power.

Doesn't have to be very quickly.

I'm used to LEDs getting very very upset with even a minor change in
voltage/current. Maybe ultra bright ones are less sensitive?

Yeah, likely. Never seen that failure mode before
either where pressing on it sees it work again.

They clearly do fail in pairs quite a bit.

Agreed, but not as quick as I would have thought.

And I think the LED failures are due to heat. I now run them with
the
diffuser covers off to let them be cooler. I get more light out of
them
too, and I think they look better when you can see all the dots.

I'm not rapt in that result with the led strips,
particularly with the reflection off glass etc.
I havent gotten around to mounting them
properly yet, mainly because for some
reason Bunnings doesn't stock the
extrusions to mount them in in the
very long 3-4M strips and those arent
feasible to buy online in those lengths.
Bit too crude imo to have a series of 1M ones.

I use something like these:
http://www.ebay.co.uk/itm/183429947350

Yeah, plenty of those, but my led strips
are 3-4M long and its pretty crude
having so many in a line. I would
prefer to just have the one 3-4M long.

Mine plug together tightly so you barely notice the join. You can get
them different lengths, but I just buy the 2 foot ones as I can arrange
them more easily.

No use to me tho because they arent Hues.

Not sure what your fascination is with hues.

It allows complete control of brightness and
color temp and full automation of everything.

Do you like different colours depending on your mood?

No, just to be able to change the color temp to what
I prefer and to completely automate everything so
I only ever tell it to turn the main room light on
when I get up in the dark. Everything else is
completely automated, including going off
at sunrise and on at sunset and that varying
by season completely automatically.

Or are you doing something fancy with them for automation?

Yep.

If it's the latter, I find a simple PIR detector in each room is all you
need.

The Hue motion sensors allow a hell of a lot more than those do.
You specify the on time and can fiddle with the light level sensitivity
and have fancy overrides with combinations of the sequence of
what motion sensors are triggered in what sequence so the one
that sees me leave the bedroom in the dark can turn the main
room lights on forever until the sunrise turns them off, but
when I got to the bedroom in the evening, it turns the bedroom
light on for a short time and turns the main room lights off.

If I or a pet is moving in the room, the light comes on for a set time,
then goes off if it hasn't seen any movement.

I do that for the shower room and beer storage rooms
but want something more fancy for the main room.

In rooms such as the lounge where I'm likely to be sat still for long
periods watching TV, I set it to 15 minutes.

That wont work here because I need to have it turn the
main room lights on when leaving the bedroom in the
dark in the morning, but that sensor can't see me when
I am sitting in the armchair that I compute from and
that I eat everything when sitting on.

For the bedroom it's 20 seconds so I don't have to wait for darkness to
get to sleep.

Trouble is that it's the same movement sensor
for that one and that's used to turn the main
room lights on when getting up in the morning
so I need to have a different action based on
the time of day the movement is detected.

The other approach with leds is to just have
the entire house either on or off, all the lights.
But that likely would see a reduced life of
the leds and in the hottest weather I actually
prefer not to have the main room all lit up
in the hot summer evenings.

My bedroom has one 2 foot strip. The bathroom has two, but seperate
with
a gap inbetween. The lounge has 4 singles and 4 joined together and a
single corn shaped one, the kitchen has 5 joined together and singles
under the wall cupboards, the garage has 8, 5 joined and 3 joined.

They are available, but Bunnings doesn't stock them.

Ever heard of Ebay?

Corse I have but no one ships 3-4M long stuff by post or courier.
Bunnings have their trucks moving the long stuff.

Something wrong with Aussie couriers then,

Nope.

I just bought thirty enormous panels of welded mesh for some pet caging.
They came by courier, on a large truck.

Ours use vans to deliver around town.

All I need is to screw a small clip every 2 feet into the ceiling,

I want mine much lower than that in the kitchen, just 2M or so from
the ground

Er... I put my lights on the ceiling. Why would you want anything else?

and I don't have overhead cupboards so want to run a
24mm RHS with the extrusion stuck to it with decent double sided
tape or pop riveted onto the RHS occasionally with no visible joins.

What is an RHS?

Square metal tube. Rectangular Hollow Section.

And this RHS runs along your ceiling?

No.

Or is suspended lower than your very high ceiling?

It is lower than the ceiling, but not suspended from
it. Each end is attached to the wall at each end.

In that case I'd just screw the clips into the RHS, and attach them as I
already do.

But its more convenient to use double sided tape
to stick the extrusion that the led strip slides into
to the RHS or pop rivet it to the RHS.

If you don't want to screw into the RHS, just glue or tape the 2 foot
strips I use straight onto the RHS (the back of them is perfectly flat).

The led strip is a continuous 3-4M
long strip of leds on a flexible pcb

and have a plug with 240V at the end.

Yeah, that part is easy and what I want.

The strips plug into each other as many as I need, and just clip onto
the
clips.

I'd prefer no visible joins but may well end up with that.

I do plan to have diffusers for those led
strips to fix the bright reflection of the
individual leds off the glass like the
front of the microwaves and wall oven
and windows.

Not sure why that would be a problem,

It isnt a problem, just doesn't look as
good as a continuous strip of light.

I dunno, I think the dots look pretty.

They look a bit odd when reflected off glass.

No, they just look like dots of light,

That's what looks wrong.

same as they do looking at them directly.

Very different to when looking at them directly
because when reflected they move around on the
glass they are reflected from as you move around.

I'd find that no more annoying than a diffused light reflecting off the
glass.

But I do, likely because the dots are so bright.

I quite like those reflections.

I'd prefer a continuous strip of light.

Doesn't really bother me. I removed the diffusers only to make them run
cooler and last longer.

Same kinda idea as people liking bright halogen uplighters instead of
a
more even light throughout the room.

Sure, but those don't have 50 or so dots of light.

And each dot is MUCH dimmer than each halogen lamp.

If I wanted a more even light, I'd have to keep the diffusers on, but
the
LEDs don't last so long.

Mine should do, 3 year warranty.

I think these have a 2 or 3 year warranty, they don't last that long
with
the diffusers on though. I prefer them to last for years instead of
having to keep getting replacements.

Yeah, **** that with the expensive Hues.

**** what? Having to buy more?

Yep.

If you removed the covers they'd last longer.

You don't know that with the Hues. None have failed.

I guess I could dim them a bit instead.

I'd rather not.

Very easy to try tho and see if it works.

Looks like it would help the better ones, but not the crap one.

In fact capacitor dropper ones wont work at all when fed DC.

Agreed.

Better (as I only have a few crap ones) to stick a bigger
smoothing
cap
inside those.

Yep as long as it will fit.

They're huge inside, massive space. "Corn on the cob LED lights"
they're
called.

I don't use those, use the Hue E27 bulbs.

I only have a couple, to fit into existing bayonet fittings,

I only have the one bayonet fitting that I don't use anymore.

Yip, I've also almost got rid of traditional fittings. 3 CFLs left in
the
lounge though....

I only ever used one on the bed head light for the
much longer life than with incandescent bulbs.

Prior to the Hues I had PAR38 floods
and spots and 4' long tube fluoros.

Incandescents use way too much electricity (5 times a CFL).

Not a cost worth worrying about for me.

Bit warm tho on the hottest summer evenings.

When CFLs were invented I changed all the incandescents for those as the
incandescents failed.

I didn't bother and only used the one because it
lasted much longer than incandesxents and had
a softer turn on which meant that when turned
on in the dark you don't get blinded.

That's the other good thing about the Hues,
you can program them once to come up
gradually so you don't get blinded with
the bedroom light in the dark.

but most of my house is now the strips I linked to above.

I mostly have E27 bulbs with a couple of 3-4M led strips in the
kitchen, one above each line of benches in the twin parallel set
of benches, one against the wall and the other an island bench.

Also means nothing hangs down from the ceiling

Yeah, I don't have any like that anywhere. Don't have a dining table.

You said earlier you wanted lower lights in the kitchen?

Yeah. but not hanging down from the ceiling. They
to on a 3-4M rhs between the walls at either end.

Why do you want the lights lower than the ceiling?

Gets more light on the benchtop where its needed.

and can get knocked. Plus since the light comes from the whole strip,
no shadows from myself when I'm trying to work on something.

Yeah, that's why I have the strips in the kitchen.

I like strips everywhere. A more even light.

Don't really need even light in the main room.

It's much better, you never find yourself trying to see something in your
own shadow.

More than one light does that fine.

I could literally fit a cap about 50 times the size of the one
that's
in
it. It's probably enough smoothing with the original size, I can't
remember if it flickered when I bought it. But clearly the cap was
overworked as it failed, so I'll fit something larger so it lasts
longer
this time.

Might well just be a low quality cap, not over worked.
Rectifier caps don't get overworked when not enough uF.

Maybe it's not a low ESR cap? Maybe the high temperature in there
shortens its life?

Yeah, quite likely tho I dunno if they bulge then.
I've had very few cap failures, just one in the Humax.

I was there when the Dell PC motherboards all failed.

Never had that with any motherboards.

It was faulty batches from certain cap manufacturers, that ended up in
batches of computers (mainly Dell). We had 150 computers all go that were
purchased at a similar time.

Millions of dodgy Nichicon caps failed with a dodgy electrolyte across
the
world - called "the capacitor plague" -

It wasn't dodgy electrolyte, dodgy caps.

Wikipedia says the electrolyte was made wrong: "faulty electrolyte
mposition that caused corrosion accompanied by gas generation"

https://en.wikipedia.org/wiki/Capacitor_plague
150 PCs needed fixing under my command. Dell replaced some under
warranty, I got motherboards off Ebay to replace older ones, then when
those ran out I started desoldering the caps themselves. A bit fiddly
but
possible.

Yeah, I replaced the one in the humax. Bit of a tight fit.

I thought Humax was a decent make. Did you replace it like for like or
put a bigger one in?

Same capacitance and voltage rating but physically bigger.

Same thing happens in my PSUs for monitors.

I havent had any of the LCD monitors fail.

The two that broke are quite old ones, with seperate PSUs, with 12V or
20V
feeding into the actual monitor. Not sure why they chose to have
seperate
PSUs.

Never had any like that.

They're the only two I've had like that. Mind you I've seen caps fail the
same way inside my parents' and my neighbours' TVs, so I can't really
blame them being in a seperate box.

Or more strictly had one of the Asus monitors fail under warranty,
the backlight failing so just got it fixed under warranty.

Never had a backlight fail. Always the power caps (in TVs too), or once
I
had a chip go and one third of the screen produced random squares of
colour. I gave it away to someone who uses the other two thirds for a
Linux server.

On Sat, 22 Dec 2018 08:50:28 +1100, cantankerous trolling geezer Rot Speed,
the auto-contradicting senile sociopath, blabbered, again:

FLUSSSSHHHHHHHHHHHHHHHHHHHHHHHH

....and much better air in here!

--
Marland addressing bull****ting senile Rot:
"Stay in your wet paper bag you thick twit."
MID:

"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 19:25:49 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 04:27:41 -0000, Clare Snyder
wrote:

On Wed, 19 Dec 2018 16:39:50 -0000, "William Gothberg" "William
wrote:

On Wed, 19 Dec 2018 16:34:11 -0000, whisky-dave

wrote:

On Wednesday, 19 December 2018 16:21:43 UTC, Mark Lloyd wrote:
On 12/19/18 6:01 AM, William Gothberg wrote:

[snip]

They probably are fairly crude. I know they flicker, for example
if
I
use my cordless drill, the chuck appears to spin the wrong way
under
the
LED lighting.
I remember seeing that with a washing machine (under fluorescent
lights). As the tub was slowing down, the row of holes around the
tub
would appear to reverse direction. Same thing with (spoked) wagon
wheels
in movies.

You can also observe such things using a smartphone that has a high
FPS
rate for recodring movie.
I can see the labs lights flicker when I film at 240FPS standard 60
and everything seems fine.

Everybody seems to constantly cut corners. Lights should just be on,
no
flicker at all. ****ing annoying if you have decent eyesight, I can
see
the flicker from almost everyone's LED tail lights.


This is sounding more and more like our "engineer friend" who needs
to do his own tire repairs and alignments and clutch repairs.

Don't know who you're referring to, but what's wrong with striving for
perfection?

It increases costs for everyone who isnt a freak.

There's perfection and there's perfection. You for example like LEDs you
can control the colour of, nothing wrong with that. But OCD folk take
things too far, like washing their car every day because of two specks of
dust.

All irrelevant to whether it makes any sense to design
all car lights so that no freak ever sees any flicker at all.

"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 18:55:13 -0000, Rod Speed
wrote:



"William Gothberg" "William wrote in message
news
On Thu, 20 Dec 2018 08:19:58 -0000, gregz wrote:

Clare Snyder wrote:
On Wed, 19 Dec 2018 19:34:57 -0000, "William Gothberg" "William
wrote:

On Wed, 19 Dec 2018 18:03:19 -0000, Clark W. Griswold
wrote:

On 12/19/2018 11:36 AM, William Gothberg wrote:
On Wed, 19 Dec 2018 16:18:29 -0000, Mark Lloyd
wrote:

On 12/19/18 5:23 AM, William Gothberg wrote:
Do switch mode power supplies flicker in time with mains?
Specifically
LED power supplies in commercially available domestic lamps. By
in
time, I don't mean at the same 50/60Hz, but anchored to it. I.e.
if
you
have several such lamps each with their own built in supply, will
they
all flicker in time, using the mains frequency to keep them in
time, or
will they be random, making the room overall not flicker due to
them all
being random? And is there any way I can test this? I tried
taking
photos of them, but my camera only goes as fast as 1/2000th of a
second,
which shows all the lights at the same brightness each time, I
suspect
the flicker is above 2000Hz.

I once had an audio amplifier with a solar cell rather than a
microphone
for the input transducer. This made it possible to listen to
light.
The
sun is steady, incandescent lights (AC powered) hum.

That was 40 years ago. Maybe something like that would work today.

The trouble is I want to compare 2kHz+ from one light with 2kHz+
from
a neighbouring light and see if they're in sync.

Maybe use a dual trace oscilloscope?

Haven't got one unfortunately.

Since this landed in alt.home.repair, I gotta ask. Do you have
single-phase or two-phase?

Single. I'm in the UK.
so 50 Htz - you can almost see an incandescent flicker at that
frequency (at 25 you could)

(also rules out the previously mentioned "engineer friend")

Lights flicker at twice the frequency, once for positive cycle, and
once
for negative cycle. LEDs only once unles using a bridge rectifier, or
steady on using DC. Even though blinking they look normal straight on,
my
brain says something is wrong

Some brains (or eyes) seem to be faster than others. I can easily (and
annoyingly) see flicker on CRT monitors below 90Hz, others don't even
see
the 50 or 60Hz ones. I can see flicker on 80% of car LED lights, others
don't see any. Designers really ought to account for those of us with
better eyesight.

No point in doing that.

There is when half the population is capable of seeing it.

Half the population isnt.

Why only sell things suitable for those with ****ty eyesight?

They are actually designed to work fine for all but freaks.

If you can't see the flicker that I can, then your eyes aren't as good as
mine.

Nothing good about eyes that see flicker everywhere.

On Sat, 22 Dec 2018 10:07:42 +1100, cantankerous trolling geezer Rot Speed,
the auto-contradicting senile sociopath, blabbered, again:



All irrelevant to whether it makes any sense to design
all car lights so that no freak ever sees any flicker at all.

What could be more irrelevant than you two blathering, brain damaged,
sociopathic idiots!

--
about senile Rot Speed:
"This is like having a conversation with someone with brain damage."
MID: