Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405

Arfa

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On 02/01/2015 14:56, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa


There is a shop in town that is all LED strip lighting. So far no
failures noticed, but I will estimate the total number of LEDs and
monitor over time. I would guess , sitting here, something like 20,000
5mm LEDs in total (not the higher powered types). I feel like running a
red/orange felt-tip along all
the cover-strips of the LED runs, as its that horrible stark blue-white.
Doesn't take much pen ink to give a much warmer tone (to CFL bulbs anyway)

This article has soldering as a dying art along with trug making etc

http://www.theguardian.com/culture/2...heritage-craft

perhaps they meant soldering as in tin-smithing.
But on the other hand how much hands-on soldering rework of modern day
mass electronics production is there?
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N_Cook wrote:

This article has soldering as a dying art along with trug making etc

http://www.theguardian.com/culture/2...heritage-craft

perhaps they meant soldering as in tin-smithing.


http://i.ebayimg.com/00/s/NDUzWDY0MA==/z/CMgAAOxyLm9TDdVl/$_12.JPG

But on the other hand how much hands-on soldering rework of modern day
mass electronics production is there?


Probably just rework on any dead items at the end of the line (if has
sufficient value) or attaching the big lumpy stuff like connectors and
transformers.

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On 02/01/2015 14:56, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa



The electronics don't have 100 components as stated and as LED lighting
becomes more widespread the support circuits will be integrated into
fewer components.

While the support electronics may be less reliable than the LED itself
other factors such as running the devices at elevated temperatures is
more likely to shorten the life. Elevated temperatures will occur if
the bulb is in an inappropriate fitting (inappropriate for a LED bulb)

If you applied the authors logic to LED backlit TVs 1 in 4 would have
already failed.


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His basic premise makes sense -- more components = lower reliability -- but
the fact is that one can easily find electronic devices 50 and 60 years old
that have never been serviced that continue to work. Members of this group
probably own them.

A failure rate of 1 in 10,000 (per year?) strikes me as unduly pessimistic,
even for devices used in vacuum tube equipment. Solid-state -- which almost
always operates at lower voltages and temperature -- should be even more
reliable.

I own devices that contain far more components than an LED bulb -- yet they do
not drop like flies. Flat-panel TVs are a good example. CU says the reported
breakdown rate is extremely low (3% for a few brands is on the high end), and
advises against purchasing service contracts.

Though the point he raises is valid, and not only deserves, but requires,
study, you can't assume these products fail prematurely simply because they
contain "too many parts". Why they failed is more important. I wouldn't be
surprised if it was due to SMD soldering failure.



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On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa

I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.

Lifetime guarantee. If you can find where to send it and pay
more in shipping it back than the cost of replacement.
And it's not the lifetime of the light. It's the lifetime
of the supplier.

Home lamps are designed for cheap,cheap,cheap,
not for reliability. But it will get better over time.

I always giggle at flashlights that say you never replace the LED,
over 20,000 hour life, etc.
The elephant in the room is that in most cheap designs, they
put the LED directly across three batteries and hope the battery
resistance increases faster than the time it takes to melt the light.
And the better designs have a dozen high-stress parts in
some regulator.

I sawed a free harbor freight flashlight in half and soldered it
back together to make an extension. Put an 18650 in an extended light.
Really bright. Replacing three 1.5V with one 4.2V oughta work, right?
Not for long...but far longer than I expected. Put one ohm in series
and it looks like life might be ok. ;-) Still pretty bright.
There's a reason they ship with heavy duty batteries.

Home Depot has some really great deals if you watch closely.
I bought 44 40W LED's when they were 4 for $5.05 and replaced
most of my CFL. Turns out that two 40's in a Y-adapter was
way cheaper than a 60W and had better light dispersion.
Then they had 60W at 3 for $6.97 to replace 12 of the 40's.
Then they had 75W at ONE CENT. I bought all 8 of them to replace
some of the 60's.

There's no possible financial reason for doing that.
I tell myself that the LED's should last longer in applications
where you switch them on and off a lot. But I put LED's in fixtures
I haven't turned on in years. Don't judge me...I'm saving the planet...

In the attic, I have about a hundred used incandescents, right
next to the hundred CFL's, right next to all the spare LED's
I bought but never used.
Right next to the box of flashlights I couldn't help buying.
And I still mine Home Depot for LED deals. I need to go
to rehab for LED abuse.

Often we do stuff because we can, not because we should.

If I remember correctly, if you combine the MTBF of all the components,
the probability of system failure within the system MTBF is 37%.

Are we having fun yet?

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"Arfa Daily" wrote in message
...
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Mindlessly superficial.

If that mindlessly superficial approach was correct,
we'd all be using a pencil instead of computers.

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In sci.electronics.repair mike wrote:
On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa

I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.


I've had a couple CFLs burn out at the bulb from old age. Most had
electronic failures, or jsut broke.

The longest lasting CFL may be one in my bathroom with 10 years of
on-off use. I'd have to remove it to checked the purchase date I write on
them though.



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"N_Cook" wrote in message
...
On 02/01/2015 14:56, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa


There is a shop in town that is all LED strip lighting. So far no failures
noticed, but I will estimate the total number of LEDs and monitor over
time. I would guess , sitting here, something like 20,000 5mm LEDs in
total (not the higher powered types). I feel like running a red/orange
felt-tip along all
the cover-strips of the LED runs, as its that horrible stark blue-white.
Doesn't take much pen ink to give a much warmer tone (to CFL bulbs anyway)


This article has soldering as a dying art along with trug making etc
http://www.theguardian.com/culture/2...heritage-craft


Just more mindlessly silly journalism.

There might be only one person still making denim
on that soggy little island, but plenty in china.

perhaps they meant soldering as in tin-smithing.


Corse they did and they're wrong about that too.

But on the other hand how much hands-on soldering rework of modern day
mass electronics production is there?


Quite a bit actually. Forget what they were making but
someone posted a link to a youtube of a factory in china
making something like a video camera or something.

Lots of hand soldering going on.

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On 02/01/2015 15:19, N_Cook wrote:

There is a shop in town that is all LED strip lighting. So far no
failures noticed, but I will estimate the total number of LEDs and
monitor over time.


Our office has been up-and-running for less than 6 months. I don't know
when it was fitted out, but the LED lights in the conference rooms are
on clever circuits so they come on only when they are used - and our
floor was empty.

One of them has died. Not the LEDs, but the driver - it's a square
luminaire with LEDs on each side, and one side flashed.

Andy


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In sci.electronics.repair Cydrome Leader wrote:
In sci.electronics.repair mike wrote:
On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa

I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.


I've had a couple CFLs burn out at the bulb from old age. Most had
electronic failures, or jsut broke.

The longest lasting CFL may be one in my bathroom with 10 years of
on-off use. I'd have to remove it to checked the purchase date I write on
them though.


I've had a few CFL's fail due to electronics failure, but the newer
bulbs last longer. Unfortunately as they age they get dimmer. Looking
at an aged bulb I noticed that the phosphor layer has turned a brownish
color.

I did have one failure that when I took it apart, 1 of the wires to to
the flourescent was disconnected & the others were questionable.
Soldered them all & re-assembled the bulb and it's still in use in the
basement bathroom.

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In sci.electronics.repair Jerry Peters wrote:
In sci.electronics.repair Cydrome Leader wrote:
In sci.electronics.repair mike wrote:
On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa
I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.


I've had a couple CFLs burn out at the bulb from old age. Most had
electronic failures, or jsut broke.

The longest lasting CFL may be one in my bathroom with 10 years of
on-off use. I'd have to remove it to checked the purchase date I write on
them though.


I've had a few CFL's fail due to electronics failure, but the newer
bulbs last longer. Unfortunately as they age they get dimmer. Looking
at an aged bulb I noticed that the phosphor layer has turned a brownish
color.


I'd have to agree that the newer ones seem a bit better. They've figured
out how make them as simple as possible now is my guess.

I did have one failure that when I took it apart, 1 of the wires to to
the flourescent was disconnected & the others were questionable.
Soldered them all & re-assembled the bulb and it's still in use in the
basement bathroom.


they're still useless for outdoor cold use. The ones outside by the stairs
are like nightlights when the temps drop to freezing. It's amazing they
even start.

I'm not a fan of the warm up period they take, even indoors.
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"Cydrome Leader" wrote in message
...
In sci.electronics.repair Jerry Peters wrote:
In sci.electronics.repair Cydrome Leader wrote:
In sci.electronics.repair mike wrote:
On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa
I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.

I've had a couple CFLs burn out at the bulb from old age. Most had
electronic failures, or jsut broke.

The longest lasting CFL may be one in my bathroom with 10 years of
on-off use. I'd have to remove it to checked the purchase date I write
on
them though.


I've had a few CFL's fail due to electronics failure, but the newer
bulbs last longer. Unfortunately as they age they get dimmer. Looking
at an aged bulb I noticed that the phosphor layer has turned a brownish
color.


I'd have to agree that the newer ones seem a bit better. They've figured
out how make them as simple as possible now is my guess.

I did have one failure that when I took it apart, 1 of the wires to to
the flourescent was disconnected & the others were questionable.
Soldered them all & re-assembled the bulb and it's still in use in the
basement bathroom.


they're still useless for outdoor cold use. The ones outside by the stairs
are like nightlights when the temps drop to freezing. It's amazing they
even start.

I'm not a fan of the warm up period they take, even indoors.


I like it with the bedhead light. You don’t get the same
blinding effect when you turn it on in the dark.

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Cydrome Leader wrote:
In sci.electronics.repair Jerry wrote:
In sci.electronics.repair Cydrome wrote:
In sci.electronics.repair wrote:
On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa
I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.

I've had a couple CFLs burn out at the bulb from old age. Most had
electronic failures, or jsut broke.

The longest lasting CFL may be one in my bathroom with 10 years of
on-off use. I'd have to remove it to checked the purchase date I write on
them though.


I've had a few CFL's fail due to electronics failure, but the newer
bulbs last longer. Unfortunately as they age they get dimmer. Looking
at an aged bulb I noticed that the phosphor layer has turned a brownish
color.


I'd have to agree that the newer ones seem a bit better. They've figured
out how make them as simple as possible now is my guess.

I did have one failure that when I took it apart, 1 of the wires to to
the flourescent was disconnected& the others were questionable.
Soldered them all& re-assembled the bulb and it's still in use in the
basement bathroom.


they're still useless for outdoor cold use. The ones outside by the stairs
are like nightlights when the temps drop to freezing. It's amazing they
even start.

I'm not a fan of the warm up period they take, even indoors.


Interesting, my outside CFLs are over 35yrs old and start down to -8C
without fail. My newer CFLs, die like flies in comparison, particularly
in glass globe fittings. I reckon some CFLs have as short a life as
filament bulbs, even when running cool..
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Capitol wrote:


Iteresting, my outside CFLs are over 35yrs old and start down to -8C
without fail.



** The CFLs on sale in the 1980s used iron ballasts and most had replaceable bulbs. When used as outdoor night lights on a premises, bulb lifespan is 1 to 2 years or about 8000 hours.


My newer CFLs, die like flies in comparison, particularly
in glass globe fittings.


** The last CFL I used as a night light lasted 4 years.

Naturally, it was cycled only once per day and that is the secret.


..... Phil


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"Cydrome Leader" wrote in message ...

I'm not a fan of the warm up period they take, even indoors.


Recent models come to full brightness quickly.


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On 02/01/2015 21:09, Jerry Peters wrote:


I've had a few CFL's fail due to electronics failure,



+1
http://www.admac.myzen.co.uk/bulb/


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Arfa Daily wrote:

EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...lie-about-led-

lighting.html?cmp_id=7&news_id=222923405

Arfa

Yup, a lot of the consumer-grade LED lighting, at least, is
crap! Some of it is even a FIRE hazard!

I made my own LED retrofits. Not cheap, but they are working well.
I measured the power draw of the ANCIENT magnetic ballasts for
a two-lamp 48" fluorescent at 101 W. The replacement with
20 Cree "1 W" LEDs draws a measured 21 W. I used a commercial
LED lighting power supply from Digi-key. I have 3 units installed
with these Cree LEDs so far (first one was only 10 LEDs and a
home-made power supply) and I am really happy with them.

Jon
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William Sommerwerck wrote:

His basic premise makes sense -- more components = lower reliability -- but
the fact is that one can easily find electronic devices 50 and 60 years old
that have never been serviced that continue to work. Members of this group
probably own them.

A failure rate of 1 in 10,000 (per year?) strikes me as unduly pessimistic,
even for devices used in vacuum tube equipment. Solid-state -- which almost
always operates at lower voltages and temperature -- should be even more
reliable.

I own devices that contain far more components than an LED bulb -- yet they do
not drop like flies. Flat-panel TVs are a good example. CU says the reported
breakdown rate is extremely low (3% for a few brands is on the high end), and
advises against purchasing service contracts.

Though the point he raises is valid, and not only deserves, but requires,
study, you can't assume these products fail prematurely simply because they
contain "too many parts". Why they failed is more important. I wouldn't be
surprised if it was due to SMD soldering failure.



I see a lot of LED traffic lights with groups of dead LEDs. The one
closest to me is on the fourth red LED lamp in the last couple years and
already has some groups that are quite dim.


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.
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"Vir Campestris" wrote in message
o.uk...
On 02/01/2015 15:19, N_Cook wrote:

There is a shop in town that is all LED strip lighting. So far no
failures noticed, but I will estimate the total number of LEDs and
monitor over time.


Our office has been up-and-running for less than 6 months. I don't know
when it was fitted out, but the LED lights in the conference rooms are on
clever circuits so they come on only when they are used - and our floor
was empty.

One of them has died. Not the LEDs, but the driver - it's a square
luminaire with LEDs on each side, and one side flashed.

Andy


A while back, they changed the car park lights to LED at my local Co-op
store. One of them started flashing in fairly short order, and has continued
to do so ever since, despite my repeatedly bringing it to their attention. I
suppose in the days of the metal halide lights that they had previously, the
maintenance guy would just have shinned up a ladder and replaced the lamp in
the fitting. To sort out this LED one would require the entire unit to be
unbolted from the wall, and replaced. As to the failure on the one in your
place being the driver rather than the LEDs themselves, I think that goes
along with what the guy is suggesting in the EE Times article.

Arfa



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"Rod Speed" wrote in message
...


"Arfa Daily" wrote in message
...
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Mindlessly superficial.


Much like you then ...

Arfa


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On Fri, 2 Jan 2015 14:56:48 -0000, "Arfa Daily"
wrote:

EE Times article that came to me by email today
http://www.electronics-eetimes.com/e...s_id=222923405
Arfa


What the article says is that if you calculate the MTBF of an LED
light, it will be lousy. That's true, except that it's no longer
important because such lights are designed to fail. Conspiracy theory
follows.

The problem with LED lights is that they can theoretically last
forever. All that's required is some really good heat sinking, decent
components, and AC line glitch protection. You might see those on
tower lights, runway lights, and other high reliability applications,
but not on the consumer stuff, unless the GUM (great unwashed masses)
suddenly decide that paying for quality is a good thing.

The reason for the designed in failures is the need for manufactories
to continue selling replacements. If they actually made a device that
lasts forever, they will sell a few years worth, and then go out of
business because there will be no replacement sales. Reliability is
bad for (consumer) business.

There's another problem. Anything that lasts longer than the intended
product life is considered a waste of money. For commodity items like
lighting, every penny is important because when selling millions of
lamps, the pennies add up quickly. The result is that failures are
evaluated on basis of MINIMIZING their lifetime. If something lasts
twice as long as originally intended, it is considered a candidate for
"cost reduction" which by implication means "lifetime reduction".
Ideally, the result is a product where everything fails simultaneously
one day after the warranty period. We're fairly close to the idea in
the consumer electronics and computah industry. I've seen such
simultaneous failures on the bench, especially old Sony CRT displays,
which showed evidence of intentional electrolytic capacitor lifetime
manipulation (weird voltage rating on the caps). With today's heavily
computerized design and modeling tools, it is possible to design for a
specific lifetime.

All this begs the question "Why did the author write the article"?
Scott Elder is no slouch and works for a reputable manufacturer of the
chips used to run LED lighting. Presumably, he knows how it all works
and has real data to substantiate his allegations. It seems counter
productive that an industry insider would write an article denouncing
the industry perception of LED lifetimes and reliability. My best
guess(tm) is that he's frustrated by the aforementioned penny counting
cost and lifetime reductions and wanted an indirect way to point out
the problem without appears to be a conspiratorial wacko like me.

That also begs the question "Why did Arfa Daily post the article"? My
best guess(tm) here is that he's still having problems adjusting to
LED lighting and needs a new reason to not use LED lighting. Am I at
least close?

This also begs the question "Why did I write this long rant when I
should be doing something productive"? That's easy. I like to write
conspiracy theories. It's also Friday evening, which I reserve for
working on my own projects. Finally, I've had some medical problems
lately and feel lousy enough to want to dump my problems on the world.
This is a good start.


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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On Sat, 3 Jan 2015 01:23:28 -0000, "Arfa Daily"
wrote:

"Rod Speed" wrote in message
...

"Arfa Daily" wrote in message
...
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Mindlessly superficial.


Much like you then ...
Arfa


Nothing profound has ever been said on one line.


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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mike wrote:

I've never had a CFL failure that I could trace to the CFL.



** Really? That puts you in a minority of one.

The most common CFL failure is the tube heaters going open - most are rated for only 1 to 2 thousand switch on cycles. Ones that light up quickly and tolerate low temps better seem to be the poorest at this.

All other failures I have seen are the result of the electronics section running too hot causing capacitor failure, particularly electro and EMI suppression caps.

A great many ceiling fixtures are not well suited to CFL or LED lamps cos they trap heat.


It's always the electronics driving it.


** Not true in general.

A power glitch can take
out a LED just as easily as a CFL.


** Power glitch = what ??

A line voltage spike lasting less than a mS or a hit by lighting ?

The typically 4 to 22uF electro in the DC supply absorbs brief spikes nicely and most indirect effects of lightning too.

..... Phil


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"Michael A. Terrell" wrote in message
...

William Sommerwerck wrote:

His basic premise makes sense -- more components = lower reliability --
but
the fact is that one can easily find electronic devices 50 and 60 years
old
that have never been serviced that continue to work. Members of this
group
probably own them.

A failure rate of 1 in 10,000 (per year?) strikes me as unduly
pessimistic,
even for devices used in vacuum tube equipment. Solid-state -- which
almost
always operates at lower voltages and temperature -- should be even more
reliable.

I own devices that contain far more components than an LED bulb -- yet
they do
not drop like flies. Flat-panel TVs are a good example. CU says the
reported
breakdown rate is extremely low (3% for a few brands is on the high end),
and
advises against purchasing service contracts.

Though the point he raises is valid, and not only deserves, but requires,
study, you can't assume these products fail prematurely simply because
they
contain "too many parts". Why they failed is more important. I wouldn't
be
surprised if it was due to SMD soldering failure.


I see a lot of LED traffic lights with groups of dead LEDs.


Can't say I have ever seen even one.

The one closest to me is on the fourth red LED lamp in the last
couple years and already has some groups that are quite dim.


Presumably just a very bad design.



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"Arfa Daily" wrote in message
...


"Rod Speed" wrote in message
...


"Arfa Daily" wrote in message
...
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Mindlessly superficial.


Much like you then ...


You never could bull**** your way out of a wet paper bag.

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"Jeff Liebermann" wrote in message
...
On Fri, 2 Jan 2015 14:56:48 -0000, "Arfa Daily"
wrote:

EE Times article that came to me by email today
http://www.electronics-eetimes.com/e...s_id=222923405
Arfa


What the article says is that if you calculate the MTBF of an LED
light, it will be lousy. That's true, except that it's no longer
important because such lights are designed to fail. Conspiracy theory
follows.

The problem with LED lights is that they can theoretically last
forever. All that's required is some really good heat sinking, decent
components, and AC line glitch protection. You might see those on
tower lights, runway lights, and other high reliability applications,
but not on the consumer stuff, unless the GUM (great unwashed masses)
suddenly decide that paying for quality is a good thing.

The reason for the designed in failures is the need for manufactories
to continue selling replacements. If they actually made a device that
lasts forever, they will sell a few years worth, and then go out of
business because there will be no replacement sales. Reliability is
bad for (consumer) business.

There's another problem. Anything that lasts longer than the intended
product life is considered a waste of money. For commodity items like
lighting, every penny is important because when selling millions of
lamps, the pennies add up quickly. The result is that failures are
evaluated on basis of MINIMIZING their lifetime. If something lasts
twice as long as originally intended, it is considered a candidate for
"cost reduction" which by implication means "lifetime reduction".
Ideally, the result is a product where everything fails simultaneously
one day after the warranty period. We're fairly close to the idea in
the consumer electronics and computah industry. I've seen such
simultaneous failures on the bench, especially old Sony CRT displays,
which showed evidence of intentional electrolytic capacitor lifetime
manipulation (weird voltage rating on the caps). With today's heavily
computerized design and modeling tools, it is possible to design for a
specific lifetime.


Bull****.

All this begs the question "Why did the author write the article"?
Scott Elder is no slouch and works for a reputable manufacturer of the
chips used to run LED lighting. Presumably, he knows how it all works
and has real data to substantiate his allegations. It seems counter
productive that an industry insider would write an article denouncing
the industry perception of LED lifetimes and reliability. My best
guess(tm) is that he's frustrated by the aforementioned penny counting
cost and lifetime reductions and wanted an indirect way to point out
the problem without appears to be a conspiratorial wacko like me.


Much more likely he doesn't actually have a ****ing clue about the basics.

That also begs the question "Why did Arfa Daily post the article"?
My best guess(tm) here is that he's still having problems adjusting
to LED lighting and needs a new reason to not use LED lighting.
Am I at least close?


Nope.

This also begs the question "Why did I write this long rant when
I should be doing something productive"? That's easy. I like to
write conspiracy theories. It's also Friday evening, which I reserve
for working on my own projects. Finally, I've had some medical
problems lately and feel lousy enough to want to dump my
problems on the world. This is a good start.



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On Sat, 3 Jan 2015 13:41:50 +1100, "Rod Speed"
wrote:

Much more likely he doesn't actually have a ****ing clue about the basics.


https://www.linkedin.com/pub/j-scott-elder/48/217/717
28 years experience in analog IC design. 16 patents.

Some of his blog articles:
http://www.planetanalog.com/archives.asp?section_id=526

Are you really qualified to judge whether he has a clue? I think not.


--
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150 Felker St #D
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Default Interesting ...

In sci.electronics.repair Capitol wrote:
Cydrome Leader wrote:
In sci.electronics.repair Jerry wrote:
In sci.electronics.repair Cydrome wrote:
In sci.electronics.repair wrote:
On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa
I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.

I've had a couple CFLs burn out at the bulb from old age. Most had
electronic failures, or jsut broke.

The longest lasting CFL may be one in my bathroom with 10 years of
on-off use. I'd have to remove it to checked the purchase date I write on
them though.

I've had a few CFL's fail due to electronics failure, but the newer
bulbs last longer. Unfortunately as they age they get dimmer. Looking
at an aged bulb I noticed that the phosphor layer has turned a brownish
color.


I'd have to agree that the newer ones seem a bit better. They've figured
out how make them as simple as possible now is my guess.

I did have one failure that when I took it apart, 1 of the wires to to
the flourescent was disconnected& the others were questionable.
Soldered them all& re-assembled the bulb and it's still in use in the
basement bathroom.


they're still useless for outdoor cold use. The ones outside by the stairs
are like nightlights when the temps drop to freezing. It's amazing they
even start.

I'm not a fan of the warm up period they take, even indoors.


Interesting, my outside CFLs are over 35yrs old and start down to -8C
without fail. My newer CFLs, die like flies in comparison, particularly
in glass globe fittings. I reckon some CFLs have as short a life as
filament bulbs, even when running cool..


35 years old? That thing must have been belt driven.

The oldest ones I saw were 1990-ish and from panasonic, with a huge
magnetic ballast. It was large, stupid and didn't fit in most fixtures. I
can't recall what the life was, but it was put together well with lots of
glass and silicone goop. There's no way in hell it was cheaper than a box
of incandescent bulbs, especially when you factor in the part where
electricity itself isn't really that expensive in the US.



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Jeff Liebermann wrote
Rod Speed wrote


Much more likely he doesn't actually have a ****ing clue about the
basics.


https://www.linkedin.com/pub/j-scott-elder/48/217/717
28 years experience in analog IC design. 16 patents.


Clearly doesn't have a ****ing clue about how to calculate
how long a LED light will last compared with an incandescent.

Some of his blog articles:
http://www.planetanalog.com/archives.asp?section_id=526


Are you really qualified to judge whether he has a clue?


Anyone is with that stupid claim about how long a
LED light will last compared with an incandescent.

I think not.


Not a shred of evidence that you are actually capable of rational thought.



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"Arfa Daily" wrote in message ...

EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405

Arfa

A few months ago I bought at Aldi about eight LED bulbs to use on my 240V
lighting (Australia). Three of them failed within about a month, one of them
does light up occasionally. Unfortunately I could not find the receipt for
them.

Henry

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On Fri, 02 Jan 2015 17:32:41 -0800, Jeff Liebermann wrote:


All this begs the question "Why did the author write the article"? Scott


That also begs the question "Why did Arfa Daily post the article"? My


This also begs the question "Why did I write this long rant when I


http://afterdeadline.blogs.nytimes.c...-the-question-
again/?_r=0

--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me £30a message.
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On 03/01/15 05:03, Cydrome Leader wrote:

35 years old? That thing must have been belt driven.


Philips SL probably - 35 year old this year:

http://en.wikipedia.org/wiki/Compact...scent_lamp.JPG


The oldest ones I saw were 1990-ish and from panasonic, with a huge
magnetic ballast. It was large, stupid and didn't fit in most fixtures. I
can't recall what the life was, but it was put together well with lots of
glass and silicone goop. There's no way in hell it was cheaper than a box
of incandescent bulbs, especially when you factor in the part where
electricity itself isn't really that expensive in the US.




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On 03/01/2015 05:03, Cydrome Leader wrote:
35 years old? That thing must have been belt driven.


Perhaps one of the 2D lamps? Like in the link below - but maybe the
specs. have been changed form the originals?

http://www.amazon.co.uk/16W-Energy-S.../dp/B001N7SKVU

Surely they were the precursors of the more compact CFLs? And I remember
seeing a large number of them at Preston Guildhall somewhen around the
mid-1980s or so.

--
Rod
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Well back in the days when i could see, I used to build stuff and used
solder, but increasingly even then automation for mass produced products
meant that surface mount and wire wrap techniques abounded. I'd imagine with
the banning of leaded solder its more likely that machines can make better
joints than humans even if they could use soldering stations easily.
Back then the only folk still soldering in industry were the development
types. If a pcb failed in test, then it was taken out junked and replaced.
Gone are the days when simple hands on component substitution was cost
effective it seems.
As for led lamps, I imagine they are still in the early stages of
evaluation. Nobody has had them in service long enough to refine colour temp
and reliability methods. It will probably only get better though as the
efficiency is so much better than alternatives, they are going to make it
work.
Brian

--
From the Sofa of Brian Gaff Reply address is active
"N_Cook" wrote in message
...
On 02/01/2015 14:56, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa


There is a shop in town that is all LED strip lighting. So far no failures
noticed, but I will estimate the total number of LEDs and monitor over
time. I would guess , sitting here, something like 20,000 5mm LEDs in
total (not the higher powered types). I feel like running a red/orange
felt-tip along all
the cover-strips of the LED runs, as its that horrible stark blue-white.
Doesn't take much pen ink to give a much warmer tone (to CFL bulbs anyway)

This article has soldering as a dying art along with trug making etc

http://www.theguardian.com/culture/2...heritage-craft

perhaps they meant soldering as in tin-smithing.
But on the other hand how much hands-on soldering rework of modern day
mass electronics production is there?





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On the subject - what *is* the best way to drive LEDs?

Seems to me that whilst convenient and in line with my earlier comments
on standardisation, putting little 230V PSUs in every lamp that get hot
and blow up is not the best way forward.

Does a 12V supply offer any advantages in terms of minimising on board
electronics? 12V SELV is at least standard.

If an LED has a Vf (forward voltage drop) of x volts, is it considered
good form to put 12/x LEDs in series across the supply with no other
limiting circuitry?

Or is there a really simple 2 pin current regulator on a chip available?

Old style 0.2" 20mA LEDs weren't that bothered, but I'm not au fait with
high power Crees and the like.

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"Rod Speed" wrote in message
...
Jeff Liebermann wrote
Rod Speed wrote


Much more likely he doesn't actually have a ****ing clue about the
basics.


https://www.linkedin.com/pub/j-scott-elder/48/217/717
28 years experience in analog IC design. 16 patents.


Clearly doesn't have a ****ing clue about how to calculate
how long a LED light will last compared with an incandescent.

Some of his blog articles:
http://www.planetanalog.com/archives.asp?section_id=526


Are you really qualified to judge whether he has a clue?


Anyone is with that stupid claim about how long a
LED light will last compared with an incandescent.

I think not.


Not a shred of evidence that you are actually capable of rational thought.


LOL


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Brian Gaff wrote

Well back in the days when i could see, I used to build stuff and used
solder, but increasingly even then automation for mass produced products
meant that surface mount and wire wrap techniques abounded. I'd imagine
with the banning of leaded solder its more likely that machines can make
better joints than humans even if they could use soldering stations
easily.


They still do in china as the recently posted youtube
video of one of the production lines in china shows.

Back then the only folk still soldering in industry were the development
types.


Not in china.

If a pcb failed in test, then it was taken out junked and replaced.


Not in china.

Gone are the days when simple hands on component substitution was cost
effective it seems.


Not in china.

As for led lamps, I imagine they are still in the early stages of
evaluation.


Particularly with the higher powered ones.

More production than evaluation tho.

Nobody has had them in service long enough to refine colour temp and
reliability methods.


I doubt that is true of Cree.

It will probably only get better though


Absolutely certainly.

as the efficiency is so much better than alternatives, they are going to
make it work.


They already have with quite a bit of LED stuff.

"N_Cook" wrote in message
...
On 02/01/2015 14:56, Arfa Daily wrote:
EE Times article that came to me by email today

http://www.electronics-eetimes.com/e...s_id=222923405


Arfa


There is a shop in town that is all LED strip lighting. So far no
failures noticed, but I will estimate the total number of LEDs and
monitor over time. I would guess , sitting here, something like 20,000
5mm LEDs in total (not the higher powered types). I feel like running a
red/orange felt-tip along all
the cover-strips of the LED runs, as its that horrible stark blue-white.
Doesn't take much pen ink to give a much warmer tone (to CFL bulbs
anyway)

This article has soldering as a dying art along with trug making etc

http://www.theguardian.com/culture/2...heritage-craft

perhaps they meant soldering as in tin-smithing.
But on the other hand how much hands-on soldering rework of modern day
mass electronics production is there?



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In message , Cydrome Leader
writes
In sci.electronics.repair Capitol wrote:
Cydrome Leader wrote:
In sci.electronics.repair Jerry wrote:
In sci.electronics.repair Cydrome wrote:
In sci.electronics.repair wrote:
On 1/2/2015 6:56 AM, Arfa Daily wrote:
EE Times article that came to me by email today


http://www.electronics-eetimes.com/e...out-led-lighti
ng.html?cmp_id=7&news_id=222923405


Arfa
I've never had a CFL failure that I could trace to the CFL.
It's always the electronics driving it. A power glitch can take
out a LED just as easily as a CFL.

I've had a couple CFLs burn out at the bulb from old age. Most had
electronic failures, or jsut broke.

The longest lasting CFL may be one in my bathroom with 10 years of
on-off use. I'd have to remove it to checked the purchase date I write on
them though.

I've had a few CFL's fail due to electronics failure, but the newer
bulbs last longer. Unfortunately as they age they get dimmer. Looking
at an aged bulb I noticed that the phosphor layer has turned a brownish
color.

I'd have to agree that the newer ones seem a bit better. They've figured
out how make them as simple as possible now is my guess.

I did have one failure that when I took it apart, 1 of the wires to to
the flourescent was disconnected& the others were questionable.
Soldered them all& re-assembled the bulb and it's still in use in the
basement bathroom.

they're still useless for outdoor cold use. The ones outside by the stairs
are like nightlights when the temps drop to freezing. It's amazing they
even start.

I'm not a fan of the warm up period they take, even indoors.


Interesting, my outside CFLs are over 35yrs old and start down to -8C
without fail. My newer CFLs, die like flies in comparison, particularly
in glass globe fittings. I reckon some CFLs have as short a life as
filament bulbs, even when running cool..


35 years old? That thing must have been belt driven.


Philips brought out a bayonet fitting CFL late '70's. Very heavy for
pendant drops!

Our outside lamps are CFLs fitted in 1995. No failures although they
don't get much use.

The oldest ones I saw were 1990-ish and from panasonic, with a huge
magnetic ballast. It was large, stupid and didn't fit in most fixtures. I
can't recall what the life was, but it was put together well with lots of
glass and silicone goop. There's no way in hell it was cheaper than a box
of incandescent bulbs, especially when you factor in the part where
electricity itself isn't really that expensive in the US.




--
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On 02/01/2015 19:22, William Sommerwerck wrote:
His basic premise makes sense -- more components = lower reliability --
but the fact is that one can easily find electronic devices 50 and 60
years old that have never been serviced that continue to work. Members
of this group probably own them.

A failure rate of 1 in 10,000 (per year?) strikes me as unduly
pessimistic, even for devices used in vacuum tube equipment. Solid-state
-- which almost always operates at lower voltages and temperature --
should be even more reliable.

I own devices that contain far more components than an LED bulb -- yet
they do not drop like flies. Flat-panel TVs are a good example. CU says
the reported breakdown rate is extremely low (3% for a few brands is on
the high end), and advises against purchasing service contracts.

Though the point he raises is valid, and not only deserves, but
requires, study, you can't assume these products fail prematurely simply
because they contain "too many parts". Why they failed is more
important. I wouldn't be surprised if it was due to SMD soldering failure.



The Haswell-E die is composed of 2.6 billion transistors. You have to
achieve phenomenal component reliability for any of them to work as they
leave the factory, let alone years later! Adding up everything in a
typical modern PC including the display leads to even huger numbers of
components. Yet we see many of them struggle on for many years until
they are replaced, all too often, due to inadequate computing power (or
not being able to justify the complete re-install of an updated OS on an
old box) rather than component failure.

--
Rod
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