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