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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On 03/01/2015 11:43, Huge wrote:
Nothing profound has ever been said by Rod Speed.



I don't know, "Profound from Latin profundus : prō-, before; see pro-1 +
fundus, bottom." :-)

--
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On 03/01/15 13:03, polygonum wrote:
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.

The deeper analysis asks the question 'what fails, and why?'

In general a chip once made, wont degrade catastrophically. Its
thermally stable, and any manufacturing faults show up on test or early on.

Yes, RAM and other chops do age, but there is a wide tolerance before
they go so far out of spec they are useless.

By far the greatest killer is heat: heat accelerates ageing., death
occurs in microseconds at 180C, decades at 30C



--
Everything you read in newspapers is absolutely true, except for the
rare story of which you happen to have first-hand knowledge. Erwin Knoll
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"Huge" wrote in message ...
On 2015-01-02, 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.


This is a category error. Yes, we all have 'n' year-old electronic devices,
because we have thrown away the ones that have failed.


That's logically correct. But I have 40 to 50 year old Sony and KLH products
that work fine. Whereas Sony stuff from the last 15 years is gradually falling
apart.

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"polygonum" wrote in message ...

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!


One might argue that all the transistors are created simultaneously in a
single processing sequence, and that the chip is, technically, a single
component.

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"Jeff Liebermann" wrote in message
...

Nothing profound has ever been said on one line.


Including that statement?



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"Jeff Liebermann" wrote in message
...

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.


What about lighting for new buildings?

From my perspective, the cost savings outweigh the "premature" failures.


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.


Like most people, Arfa doesn't like high-K lighting. I switched to 5000K CFLs,
and though it took a couple of weeks to adjust, I much prefer light that
more-closely resembles daylight, and is subjectively brighter.

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"Rod Speed" wrote in message ...

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


Are you any relation to Joshua Speed?

Arfa is an intelligent and knowledgeable person. You do not come off as very
bright (joke intended) making such a broad attack.

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On 03/01/15 15:03, William Sommerwerck wrote:
"polygonum" wrote in message ...

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!


One might argue that all the transistors are created simultaneously in a
single processing sequence, and that the chip is, technically, a single
component.

In general its also a tested component.

so it works to spec or it doesn't.

*Failure* of a system that worked to start with implies change over
time: The relevant point is what changes happen to circuits over time
and what law if any, they follow.



--
Everything you read in newspapers is absolutely true, except for the
rare story of which you happen to have first-hand knowledge. Erwin Knoll
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On 03/01/2015 15:03, William Sommerwerck wrote:
"polygonum" wrote in message ...

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!


One might argue that all the transistors are created simultaneously in a
single processing sequence, and that the chip is, technically, a single
component.


One might argue that is the case for the 100-component circuit referred
to in the EE Times article. I simply do not know what goes on in the
making of "an LED plus its associated circuitry". Is it made as one,two
or 101 components?

--
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On 03/01/2015 15:10, William Sommerwerck wrote:
Like most people, Arfa doesn't like high-K lighting. I switched to 5000K
CFLs, and though it took a couple of weeks to adjust, I much prefer
light that more-closely resembles daylight, and is subjectively brighter.


I too prefer higher K lamps - though probably 4200 to 4500 rather than
5000. I get the feeling that the 2700 ones started out as OK LEDs but
someone adjusted it until it was a yellow as a candle.

Also want the best possible CRI.

--
Rod


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"polygonum" wrote in message ...
On 03/01/2015 15:03, William Sommerwerck wrote:

One might argue that all the transistors are created simultaneously in a
single processing sequence, and that the chip is, technically, a single
component.


One might argue that is the case for the 100-component circuit referred to
in the EE Times article.


One //might not// argue that. The LED lamp is made of discrete components that
are manufactured separately, and individually soldered in place.

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On Sat, 3 Jan 2015 07:05:05 -0800, "William Sommerwerck"
wrote:

"Jeff Liebermann" wrote in message
.. .

Nothing profound has ever been said on one line.


Including that statement?


Of course. Everything I write has a hidden meaning, hidden agenda,
hidden target, or hidden oxymoron.

The problem here is that while I respect the rights of every person to
have an opinion in accordance with freedom of speech, I don't really
care what that opinion might be. I'm interested in the reasoning
behind that opinion, the logic used to arrive at the opinion, and
possibly some examples of why that opinion is correct and others
wrong. I'll then weight all the sides of the discussion, relative to
my needs, and make my own decision. Circumventing this logic process
by merely offering an opinion is a waste of time and bytes.

Also, the proliferation of one-line comments on the web and Usenet
make me suspect that the literacy of those involved is deficient. I
can speculate endlessly as to the reasons for this deterioration in
literacy. One of the more interesting causes is coupled with another
problem. Posters with questions often supply as little information as
possible and require interrogation in order to extract the facts.
One-liners and lack of info are symptoms of the same problem, fear of
screwing up. The more one writes, the easier it is for someone else
to find an error, omission, or logic fault. Rather than be caught
making a mistake, it is much easier to not present a targets.

"Better to remain silent and be thought a fool than to speak out and
remove all doubt"? (Abraham Lincoln).

It's also possible that the perpetrators of one-liners are stuck in a
write only mode, where they care little about those that might read
the comments. That would class them only slightly better than a
spammer that doesn't read the newsgroup before or after posting their
junk. If this is the problem, I suggest that people posting anything
first consider a simple litmus test. If you don't like reading what
you're about to post, then don't post it.


--
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 03/01/15 10:57, Tim Lamb wrote:
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!


Still using a Phillips CFL bought around 1985, rated at 18w, and about a
dozen cm in diameter. Works well, with no obvious loss of light once
warmed up, although it was used only for 3 or 4 years when first bought,
and not used again until a couple of years ago. As you say, it's pretty
heavy!

--

Jeff
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On 3 Jan 2015 06:50:55 GMT, Bob Eager wrote:

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.com/2008/09/25/begging-the-question-again/?_r=0


Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.

If your one-line comment is about my use of "begs the question",
you're correct that mine was not the correct usage. It should have
been "raises the question" as described in:
http://begthequestion.info
My appologies. I'll instruct my proof reader to check for such
grammatical errors.


--
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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Huge wrote
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.


This is a category error.


No.

Yes, we all have 'n' year old electronic devices, because
we have thrown away the ones that have failed.


And yet cars are in fact MUCH more reliable now even tho
they have a lot more components than they used to have.

Same with other stuff like TVs etc too.


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On Sat, 03 Jan 2015 10:19:37 -0800, Jeff Liebermann wrote:

Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.


Please spell carats correctly and cease the apostrophe abuse so that we
don't have to wrap your lines...
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William Sommerwerck wrote
Rod Speed wrote


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


Are you any relation to Joshua Speed?


No idea, I've never done the
genealogy that comprehensively.

I do know that I am not related to quite
a few other Speeds in my country even
tho it is a rather uncommon name.

Arfa is an intelligent and knowledgeable person.


He clearly isn't on that particular question.

He didn't even notice that cars are MUCH
more reliable than they used to be even
tho they have vastly more components
than they used to have. In spades with
computer cpus and memory alone.
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On Sat, 3 Jan 2015 07:10:25 -0800, "William Sommerwerck"
wrote:

"Jeff Liebermann" wrote in message
.. .

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.


What about lighting for new buildings?


It's strictly a question of selling price.

Joe Sixpack is not going to tolerate $8 "60 watt" lamps in his house.
He wants cheap, at any cost, even if it blows up every few years. I've
noticed that most of the homes that I see that have all LED lighting,
also have a hybrid car, grid tied solar systems, and other energy
conservation devices. They tend to be affluent but not very good at
calculating the alleged savings or comparing with alternatives. When
I do this for them, some don't want to hear the bad news. They'll pay
any price, to save a few pennies. Seriously expensive LED lighting is
not a problem for this market.

However, the rest are tightwads or just plain cheap. They look at the
store shelf and see $1 CCFL lamps next to $10 LED lights. My guess is
they'll buy the $1 lamp and wait for the price of LED's to drop. I
saw this happen at the local hardware store. The flooring manager
said that when he puts the two types of lights next to each other, the
sales of CCFL lamps go up and LED's drop. When he separates them,
putting the LED's in a garish impulse buy display near the cash
register, CCFL sales drop, and LED's go up. The bottom line is that
Joe Sixpack wants cheap lights, and the only way the industry is going
to supply those is to cut corners, which show up as increased infant
mortality and lifetime failures.

However, high reliability lighting (towers, airports, buildings, etc)
are in a different class from Joe Sixpack. You don't find those
lights at the hardware store or supermarket. They're industrial
specialty items, with high quality LED's, and high prices to match.
Reputation is a big thing in such markets, so anything designed to
fail prematurely is not going to last very long.

From my perspective, the cost savings outweigh the "premature" failures.


That totally depends on how you rate lifetime. I get about 2 years on
most of my commodity CCFL lights. I haven't blown out enough lights
to produce useful statistics, but mostly I break them from impact
damage, or something in the electronics burns out, usually with a puff
of smog and a noxious smell. A capacitor would be my guess from the
smell.

However, these are not the best CCFL lights. Why would this company
advertise that their CCFL lamps have 2.5 to 6.6 times the lifetime of
ordinary CCFL lamps?
http://www.ccfllamps.com/_en/02_technology/01_detail.php?fid=3
Is it because their lamps are better, or because the ordinary CCFL
lamps have been cost reduced to produce a shorter lifetime? Dunno,
but I suspect the latter.

LED's are probably similar. You can get those that last forever, and
those that are cost reduced to blow up just after the warranty
expires. If you do the math, my guess is the price/performance ratio
is about the same.

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.


Like most people, Arfa doesn't like high-K lighting. I switched to 5000K CFLs,
and though it took a couple of weeks to adjust, I much prefer light that
more-closely resembles daylight, and is subjectively brighter.


It's been a while, but I recall that he could not adjust to LED
lighting. He's not the only one. The neighboring architects office
has two people that claim eyestrain from the replacement LED lighting.
Their section of the office uses ordinary fluorescent tubes and
incandescent desk lamps. (I once suggested kerosene lamps with
predictable results).

I've done some testing on myself to see what works best. 6000K
daylight LED lighting seems best for doing fine detail work.
2700-3000K is much easier on my eyes for reading, but I have trouble
focusing on detail and fine print. I use both where appropriate.

--
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 01/03/2015 7:10 AM, William Sommerwerck wrote:
"Jeff Liebermann" wrote in message
...

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.


What about lighting for new buildings?


My son-in-law is working on that problem. They manufacture light pipes
that bring outside light sources - the sun, high intensity electric,
etc. - and transport that throughout buildings (up to 50 feet) using
light pipes that drop it down everywhere needed. They are having great
fun with this!

http://www.suncentralinc.com/

From my perspective, the cost savings outweigh the "premature" failures.


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.


Like most people, Arfa doesn't like high-K lighting. I switched to 5000K
CFLs, and though it took a couple of weeks to adjust, I much prefer
light that more-closely resembles daylight, and is subjectively brighter.



--
(Please post followups or tech inquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
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On 01/03/2015 10:23 AM, Adrian wrote:
On Sat, 03 Jan 2015 10:19:37 -0800, Jeff Liebermann wrote:

Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.


Please spell carats correctly and cease the apostrophe abuse so that we
don't have to wrap your lines...


OK, guys, when we turn into language police then examples of Godwin's
Law aren't far behind...

(ducking)

John ;-#)#

--
(Please post followups or tech inquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."


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On 01/03/2015 7:00 AM, William Sommerwerck wrote:
"Huge" wrote in message ...
On 2015-01-02, 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.


This is a category error. Yes, we all have 'n' year-old electronic
devices,
because we have thrown away the ones that have failed.


That's logically correct. But I have 40 to 50 year old Sony and KLH
products that work fine. Whereas Sony stuff from the last 15 years is
gradually falling apart.


And I have a lovely Phillips reel-to-reel tape player (1960s) that has
had all the internal drive belts and idler tires turn to goo...a real
pain to get running again! If I ever get around to it. The electronics
all appear just fine.

Not to mention one of my first jobs in the 60s was scrapping rotted foam
sound insulation from the inside cases of IBM punch card printers, etc.
- around 1967 as I recall.

So, what can fail often has little to do with electronics, there is all
that support stuff that goes bad after its BBD (Best Before Date).

John :-#)#

--
(Please post followups or tech inquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
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On Fri, 02 Jan 2015 19:51:18 -0500, "Michael A. Terrell"
wrote:

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


I haven't. Locally, we have some LED traffic and street lights. I
have yet to see one malfunction. However, it might be simply because
the traffic department is good about quickly replacing any failures.
Most LED lights include a remote monitoring feature.

I'm not sure what might be causing the failures that you've observed.
Any sign of overheating? Power glitches? Bullet holes?

Los Angeles Saves Millions With LED Street Light Deployment
http://www.forbes.com/sites/justingerdes/2013/01/25/los-angeles-saves-millions-with-led-street-light-deployment/
After 36 months of initial operation, for instance, high-intensity
discharge (HID) fixtures in Los Angeles recorded an average failure
rate of 10%; the average failure rate for LED fixtures, according
to the latest figures, is 0.2% (189 of 98,000 installed).

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.


Got an IR temperature gun? Get as close as you can and get a
temperature reading. My guess(tm) is that it's running hot, even with
some blown lights.

--
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 1/3/2015 1:54 PM, Jeff Liebermann wrote:
On Sat, 3 Jan 2015 07:10:25 -0800, "William Sommerwerck"
wrote:

"Jeff Liebermann" wrote in message
...

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.


What about lighting for new buildings?


It's strictly a question of selling price.

Joe Sixpack is not going to tolerate $8 "60 watt" lamps in his house.
He wants cheap, at any cost, even if it blows up every few years. I've
noticed that most of the homes that I see that have all LED lighting,
also have a hybrid car, grid tied solar systems, and other energy
conservation devices. They tend to be affluent but not very good at
calculating the alleged savings or comparing with alternatives. When
I do this for them, some don't want to hear the bad news. They'll pay
any price, to save a few pennies. Seriously expensive LED lighting is
not a problem for this market.

However, the rest are tightwads or just plain cheap. They look at the
store shelf and see $1 CCFL lamps next to $10 LED lights. My guess is
they'll buy the $1 lamp and wait for the price of LED's to drop. I
saw this happen at the local hardware store. The flooring manager
said that when he puts the two types of lights next to each other, the
sales of CCFL lamps go up and LED's drop. When he separates them,
putting the LED's in a garish impulse buy display near the cash
register, CCFL sales drop, and LED's go up. The bottom line is that
Joe Sixpack wants cheap lights, and the only way the industry is going
to supply those is to cut corners, which show up as increased infant
mortality and lifetime failures.

However, high reliability lighting (towers, airports, buildings, etc)
are in a different class from Joe Sixpack. You don't find those
lights at the hardware store or supermarket. They're industrial
specialty items, with high quality LED's, and high prices to match.
Reputation is a big thing in such markets, so anything designed to
fail prematurely is not going to last very long.

From my perspective, the cost savings outweigh the "premature" failures.


That totally depends on how you rate lifetime. I get about 2 years on
most of my commodity CCFL lights. I haven't blown out enough lights
to produce useful statistics, but mostly I break them from impact
damage, or something in the electronics burns out, usually with a puff
of smog and a noxious smell. A capacitor would be my guess from the
smell.

However, these are not the best CCFL lights. Why would this company
advertise that their CCFL lamps have 2.5 to 6.6 times the lifetime of
ordinary CCFL lamps?
http://www.ccfllamps.com/_en/02_technology/01_detail.php?fid=3
Is it because their lamps are better, or because the ordinary CCFL
lamps have been cost reduced to produce a shorter lifetime? Dunno,
but I suspect the latter.

LED's are probably similar. You can get those that last forever, and
those that are cost reduced to blow up just after the warranty
expires. If you do the math, my guess is the price/performance ratio
is about the same.

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.


Like most people, Arfa doesn't like high-K lighting. I switched to 5000K CFLs,
and though it took a couple of weeks to adjust, I much prefer light that
more-closely resembles daylight, and is subjectively brighter.


It's been a while, but I recall that he could not adjust to LED
lighting. He's not the only one. The neighboring architects office
has two people that claim eyestrain from the replacement LED lighting.
Their section of the office uses ordinary fluorescent tubes and
incandescent desk lamps. (I once suggested kerosene lamps with
predictable results).

I've done some testing on myself to see what works best. 6000K
daylight LED lighting seems best for doing fine detail work.
2700-3000K is much easier on my eyes for reading, but I have trouble
focusing on detail and fine print. I use both where appropriate.


I have a bunch of Luxo desk lamps that have a 100 W incandescent
surrounded by a 22W circular fluorescent. They're by far the easiest
thing on the eyes that I've ever used.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net
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Jeff Liebermann wrote
William Sommerwerck wrote
Jeff Liebermann wrote


Nothing profound has ever been said on one line.


Including that statement?


Of course. Everything I write has a hidden meaning,
hidden agenda, hidden target, or hidden oxymoron.


The problem here is that while I respect the rights of every person to
have an opinion in accordance with freedom of speech, I don't really
care what that opinion might be. I'm interested in the reasoning
behind that opinion, the logic used to arrive at the opinion, and
possibly some examples of why that opinion is correct and others
wrong. I'll then weight all the sides of the discussion, relative to
my needs, and make my own decision. Circumventing this logic
process by merely offering an opinion is a waste of time and bytes.


Also, the proliferation of one-line comments on the web and Usenet
make me suspect that the literacy of those involved is deficient.


That line can't explain why some like Churchill specialised in
stinging one liners. Hard to claim his literacy was deficient.

I can speculate endlessly as to the reasons for this deterioration in
literacy. One of the more interesting causes is coupled with another
problem. Posters with questions often supply as little information
as possible and require interrogation in order to extract the facts.


That has always been a problem. Plenty just don't understand that
'it doesn't work anymore' isnt every useful for working out why it doesn't.

One-liners and lack of info are symptoms
of the same problem, fear of screwing up.


I don't buy that with one liners with people like Churchill.

The more one writes, the easier it is for someone
else to find an error, omission, or logic fault.


Yes.

Rather than be caught making a mistake,
it is much easier to not present a targets.


I don't believe that is the reason for one
liners or the lack of detail with a fault either.

"Better to remain silent and be thought a fool than
to speak out and remove all doubt"? (Abraham Lincoln).


Another one liner.

It's also possible that the perpetrators of one-liners are stuck in
a write only mode, where they care little about those that might
read the comments. That would class them only slightly better
than a spammer that doesn't read the newsgroup before or after
posting their junk. If this is the problem, I suggest that people
posting anything first consider a simple litmus test. If you don't
like reading what you're about to post, then don't post it.


Some of us prefer Ab's one liner to your para just above.

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"Jeff Liebermann" wrote in message
...
On Sat, 3 Jan 2015 07:10:25 -0800, "William Sommerwerck"
wrote:

"Jeff Liebermann" wrote in message
. ..

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.


What about lighting for new buildings?


It's strictly a question of selling price.

Joe Sixpack is not going to tolerate $8 "60 watt" lamps in his house.
He wants cheap, at any cost, even if it blows up every few years. I've
noticed that most of the homes that I see that have all LED lighting,
also have a hybrid car, grid tied solar systems, and other energy
conservation devices. They tend to be affluent but not very good at
calculating the alleged savings or comparing with alternatives. When
I do this for them, some don't want to hear the bad news. They'll pay
any price, to save a few pennies. Seriously expensive LED lighting is
not a problem for this market.

However, the rest are tightwads or just plain cheap. They look at the
store shelf and see $1 CCFL lamps next to $10 LED lights. My guess is
they'll buy the $1 lamp and wait for the price of LED's to drop. I
saw this happen at the local hardware store. The flooring manager
said that when he puts the two types of lights next to each other, the
sales of CCFL lamps go up and LED's drop. When he separates them,
putting the LED's in a garish impulse buy display near the cash
register, CCFL sales drop, and LED's go up. The bottom line is that
Joe Sixpack wants cheap lights,


Yes.

and the only way the industry is going
to supply those is to cut corners,


No, most obviously with the change from
incandescent torches to LED torches.

which show up as increased infant mortality and lifetime failures.


No, most obviously with the change from
incandescent torches to LED torches.

And with cars in spades. MUCH more reliable than they used to be.

However, high reliability lighting (towers, airports, buildings,
etc) are in a different class from Joe Sixpack. You don't find those
lights at the hardware store or supermarket. They're industrial
specialty items, with high quality LED's, and high prices to match.
Reputation is a big thing in such markets, so anything designed
to fail prematurely is not going to last very long.


Same with systems like Amazon and ebay where
its so easy to see how long things have lasted.

And you get the short life problem even with the brand name
high end items too. Have a look at logitech mice for example.
The microswitches fail with monotonous regularity, multiple
clicking when you only intended a single click. That's been
going on for more than a decade now even with their most
expensive mice selling for $100 each with 5 or 7 year warrantys
where its in the manufacturer's interest to fix the problem
because they have to wear the replacement under warranty.

Your claim that logitech deliberately designs them
to fail like that just can't fly with warrantys like that.

From my perspective, the cost savings outweigh the "premature" failures.


That totally depends on how you rate lifetime. I get
about 2 years on most of my commodity CCFL lights.


I'm currently seeing more than 10 out of
mine and that one is used every single day.

I haven't blown out enough lights to produce useful
statistics, but mostly I break them from impact damage,


Those don't count.

or something in the electronics burns out, usually
with a puff of smog and a noxious smell. A
capacitor would be my guess from the smell.


However, these are not the best CCFL lights. Why would
this company advertise that their CCFL lamps have 2.5 to
6.6 times the lifetime of ordinary CCFL lamps?
http://www.ccfllamps.com/_en/02_technology/01_detail.php?fid=3
Is it because their lamps are better, or because the ordinary CCFL
lamps have been cost reduced to produce a shorter lifetime?


Or they have put more effort into a decent design.

Dunno, but I suspect the latter.


LED's are probably similar. You can get those that last forever,


And virtually all of the lowest power indicator leds do just that.

and those that are cost reduced to blow
up just after the warranty expires.


I don't believe that that last is even possible.

The reality with the cheapest **** from china is that
you're lucky if all of them work out of the box.

If you do the math, my guess is the
price/performance ratio is about the same.


Fraid not with my CFLs.

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.


Like most people, Arfa doesn't like high-K lighting. I switched to 5000K
CFLs, and though it took a couple of weeks to adjust, I much prefer light
that more-closely resembles daylight, and is subjectively brighter.


It's been a while, but I recall that he could not adjust to LED
lighting. He's not the only one. The neighboring architects
office has two people that claim eyestrain from the replacement
LED lighting. Their section of the office uses ordinary fluorescent
tubes and incandescent desk lamps. (I once suggested kerosene
lamps with predictable results).


I've done some testing on myself to see what works best.
6000K daylight LED lighting seems best for doing fine detail work.
2700-3000K is much easier on my eyes for reading, but I have trouble
focusing on detail and fine print. I use both where appropriate.





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On 03/01/15 10:13, Tim Watts wrote:
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.


Anyone?
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On Sat, 03 Jan 2015 10:19:37 -0800, Jeff Liebermann wrote:

Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.


I don't think you mean 'carrets' (sic) [that would be 'carets']

But I'm not sure what the right term is - I call them 'diamond brackets'.

Sorry about omitting them - as I often do, I remembered it after I
pressed the button!

--
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wish to copy them they can pay me £30a message.
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On Sat, 03 Jan 2015 18:23:51 +0000, Adrian wrote:

On Sat, 03 Jan 2015 10:19:37 -0800, Jeff Liebermann wrote:

Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.


Please spell carats correctly and cease the apostrophe abuse so that we
don't have to wrap your lines...


ITYM 'carets'!



--
My posts are my copyright and if @diy_forums or Home Owners' Hub
wish to copy them they can pay me £30a message.
Use the BIG mirror service in the UK: http://www.mirrorservice.org
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"Tim Watts" wrote in message
...
On 03/01/15 10:13, Tim Watts wrote:
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.


Anyone?


www.google.com/search?q=cree+teardown


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On 03/01/15 18:23, Adrian wrote:
On Sat, 03 Jan 2015 10:19:37 -0800, Jeff Liebermann wrote:

Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.


Please spell carats correctly and cease the apostrophe abuse so that we
don't have to wrap your lines...

Please spell *carets* correctly ....

--
Everything you read in newspapers is absolutely true, except for the
rare story of which you happen to have first-hand knowledge. Erwin Knoll


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On 03/01/2015 21:49, Bob Eager wrote:
On Sat, 03 Jan 2015 10:19:37 -0800, Jeff Liebermann wrote:

Please put carrets around URL's so that the Usenet server doesn't
reformat it by wrapping the lines.


I don't think you mean 'carrets' (sic) [that would be 'carets']

But I'm not sure what the right term is - I call them 'diamond brackets'.

Sorry about omitting them - as I often do, I remembered it after I
pressed the button!

They ain't carrats, carrets, carrots, carats nor even carets!

^
ASCII caret
(circumflex accent)

They a



Angle brackets or Less-than sign and Greater-than sign

--
Rod
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Jeff Liebermann wrote:


However, the rest are tightwads or just plain cheap. They look at the
store shelf and see $1 CCFL lamps next to $10 LED lights.



** Why "CCFL" lamps.


That totally depends on how you rate lifetime. I get about 2 years on
most of my commodity CCFL lights.


** Why "CCFL" lamps.


However, these are not the best CCFL lights. Why would this company
advertise that their CCFL lamps have 2.5 to 6.6 times the lifetime of
ordinary CCFL lamps?


** Because they ARE CCFL type lamps.

CCFL = " cold cathode fluorescent."

Same technology used for backlighting LDC screens, but made in bulb style.

Google tells me they exist, but I have never seen one.

Look like spiral CFLs but the glass tube is much finer and there are a lot more turns.


..... Phil

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On 03/01/15 22:09, john james wrote:

www.google.com/search?q=cree+teardown


Thank you - that was very informative.

Wonder if those are available here

goes off to check


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On Sat, 03 Jan 2015 20:02:10 +0000, Tim Streater
wrote:

In article , Jeff
Liebermann wrote:

problem. Posters with questions often supply as little information as
possible and require interrogation in order to extract the facts.
One-liners and lack of info are symptoms of the same problem, fear of
screwing up. The more one writes, the easier it is for someone else
to find an error, omission, or logic fault. Rather than be caught
making a mistake, it is much easier to not present a targets.


Or, of course, being inconsistent within a post. It's late, one is
tired, and so on. Much easier to make a short post than make a longer
one be coherent.


Are you sure?
"I have made this letter longer than usual, because I lack the time to
make it short" (Blaise Pascal)

I know how to make things worse. I often post to Usenet when I'm
working in my palatial office. A single long reply might be assembled
in perhaps 5 sections, spread over several hours. I frequently have a
better idea as I go along, and forget to edit the previous great idea
into something that is consistent with the latest great idea. When I
later review the posting, my reaction is usually "Did I write that"?
Sometime long and coherent are mutually exclusive.

I tend to write that way I expect others to write. As I previously
mentioned, I really don't care for one-line opinions and
pontifications. I want to read logic, reasoning, references,
examples, links to related articles, and personal experiences. That's
rather difficult to deliver in a short posting and impossible in a
one-liner.

Also, I'm quite serious about the fear of screwing up. It really bugs
me. With all the rants and conspiracy theories that I write, mistakes
are inevitable. When possible, I admit and correct my mistakes. More
often, I just turn off the computer, and go sulk for a few days.
Sometimes, there's nothing I can write that would be worth reading, so
I just disappear. Eventually, I recover and return until repeated
after my next inevitable mistake. I could greatly improve my batting
average by simply replying with a one-liner, where my ability to screw
things up is severely restricted.

--
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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Jeff Liebermann wrote
Tim Streater wrote
Jeff Liebermann wrote


Posters with questions often supply as little information as
possible and require interrogation in order to extract the facts.
One-liners and lack of info are symptoms of the same problem,
fear of screwing up. The more one writes, the easier it is for
someone else to find an error, omission, or logic fault.
Rather than be caught making a mistake, it is much
easier to not present a targets.


Or, of course, being inconsistent within a post.
It's late, one is tired, and so on. Much easier to make
a short post than make a longer one be coherent.


Are you sure?


Yep.

"I have made this letter longer than usual, because
I lack the time to make it short" (Blaise Pascal)


Another one liner from someone who is quite literate.

I know how to make things worse. I often post to Usenet when I'm
working in my palatial office. A single long reply might be assembled
in perhaps 5 sections, spread over several hours. I frequently have a
better idea as I go along, and forget to edit the previous great idea
into something that is consistent with the latest great idea. When
I later review the posting, my reaction is usually "Did I write that"?
Sometime long and coherent are mutually exclusive.


Sure, but clearly we do see the other effect he mentioned too.

I tend to write that way I expect others to write. As I previously
mentioned, I really don't care for one-line opinions


They can be useful at times, particularly when you are
saying you agree with someone else's longer post.

and pontifications.


Even pontifications have their place, particularly if you are the Pope.

I want to read logic, reasoning, references, examples,
links to related articles, and personal experiences.


Sure, but that isnt always feasible, particularly
with links to related articles in some situations.

Sometimes its useful to just post a list of possibilitys
with a problem and suggest how to test if that one
is what is happening etc.

That's rather difficult to deliver in a short
posting and impossible in a one-liner.


Yes, but one liners do have their place.
Have a look at some of Churchill's sometime.

Also, I'm quite serious about the fear
of screwing up. It really bugs me.


Sure, but it isnt something that drives everyone in the fear sense.

With all the rants and conspiracy theories
that I write, mistakes are inevitable.


Yes, and you have done that with one liners.

When possible, I admit and correct my mistakes.


You haven't done that with this one.

More often, I just turn off the computer, and go sulk for a few days.
Sometimes, there's nothing I can write that would be worth reading,
so I just disappear. Eventually, I recover and return until repeated
after my next inevitable mistake. I could greatly improve my
batting average by simply replying with a one-liner, where
my ability to screw things up is severely restricted.


Sure, but as you say, they aren't always
useful, particularly with problem solving.


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Jeff Liebermann wrote:

On Fri, 02 Jan 2015 19:51:18 -0500, "Michael A. Terrell"
wrote:

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


I haven't. Locally, we have some LED traffic and street lights. I
have yet to see one malfunction. However, it might be simply because
the traffic department is good about quickly replacing any failures.
Most LED lights include a remote monitoring feature.

I'm not sure what might be causing the failures that you've observed.
Any sign of overheating? Power glitches? Bullet holes?



This is Central Florida, so it is hot, and the electricity is crap,
since it went from Florida Power, to Progress Energy, then to Duke
Energy. They are specified and maintained by FDOT, or one of their
contractors. I've seen a few spots where they went back to the
incandescent lamp and colored lens.


Los Angeles Saves Millions With LED Street Light Deployment
http://www.forbes.com/sites/justingerdes/2013/01/25/los-angeles-saves-millions-with-led-street-light-deployment/
After 36 months of initial operation, for instance, high-intensity
discharge (HID) fixtures in Los Angeles recorded an average failure
rate of 10%; the average failure rate for LED fixtures, according
to the latest figures, is 0.2% (189 of 98,000 installed).

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.


Got an IR temperature gun? Get as close as you can and get a
temperature reading. My guess(tm) is that it's running hot, even with
some blown lights.



No, all I have is the small fob type of contactless IR thermometer.


--
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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On 1/3/2015 12:04 PM, Rod Speed wrote:


However, these are not the best CCFL lights. Why would
this company advertise that their CCFL lamps have 2.5 to
6.6 times the lifetime of ordinary CCFL lamps?
http://www.ccfllamps.com/_en/02_technology/01_detail.php?fid=3
Is it because their lamps are better, or because the ordinary CCFL
lamps have been cost reduced to produce a shorter lifetime?

It's called business.
Go to any grocery store.
Do you really believe this toothpaste gets your teeth twice as clean
as that one?
Or that your clothes will stay fresh 2X longer with this detergent?
Any claim that can't be disproved in court is a good claim.

In their zeal to get to market, it's not unusual to find that the cure
for one reliability problem introduced another. oops!

How long do you save the receipts and packaging?
Lifetime warranty is useless if you can't figger out where
to place the claim or it costs more to ship than to buy new.

With anything new, you want to reel in all the early adopters
who'll pay high prices. Product has to last until the prices
come down below shipping costs or you've changed the name on the
company nameplate.

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mike wrote:

Rod Speed wrote:


However, these are not the best CCFL lights. Why would
this company advertise that their CCFL lamps have 2.5 to
6.6 times the lifetime of ordinary CCFL lamps?
http://www.ccfllamps.com/_en/02_technology/01_detail.php?fid=3
Is it because their lamps are better, or because the ordinary CCFL
lamps have been cost reduced to produce a shorter lifetime?


** Rod did not write the above.

It's called business.



*** FFS can't you see either that "CCFL" and "CFL" are NOT the same ?


Go to any grocery store.


** Go to Google first.

Geez ....



..... Phil

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On Sat, 03 Jan 2015 10:54:18 -0800, Jeff Liebermann wrote:

However, these are not the best CCFL lights. Why would this company
advertise that their CCFL lamps have 2.5 to 6.6 times the lifetime of
ordinary CCFL lamps?
http://www.ccfllamps.com/_en/02_technology/01_detail.php?fid=3
Is it because their lamps are better, or because the ordinary CCFL
lamps have been cost reduced to produce a shorter lifetime? Dunno,
but I suspect the latter.


Interesting about the CCFLs - for a start I thought it was a typo for CFL,
but then realised that CCFLs are used in displays and last for years (mine
is nearly 8 years old but has been on for probably no more than 20,000h in
that period).
The article does seem to have a bit of trouble with its units, e.g. kW/h.

--
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whilst religions hold sway
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William Sommerwerck wrote:

polygonum wrote

William Sommerwerck wrote:

One might argue that all the transistors are created simultaneously in a
single processing sequence, and that the chip is, technically, a single
component.


One might argue that is the case for the 100-component circuit referred to
in the EE Times article.


One //might not// argue that. The LED lamp is made of discrete components that
are manufactured separately, and individually soldered in place.


The original article makes the very crude leap from one filament with a
claimed 0.0001% probability of failure (shouldn't that approach 100%
after a thousand hours?), to 60 electronic components yet assumes they
each have the same 0.0001% probability of failure, multiplying them up
to give a 60x higher failure rate for the LED vs the incandescent.

Subject to my eyesight, in the circuit chosen there appear to be 1
integrated circuit, 8 diodes, 8 transistors, 11 capacitors, 26
resistors, 2 chokes, 1 fuse.

Each of these classes of component have different probabilities of
failure, and in "cheap" PSU circuits it tends to be the capacitors with
the highest, for a given circuit a bit of analysis will probably reveal
three or four "pinch" components that are likely to be responsible for
90% of all the failures.


Searching for other LED lamp schematics, was that one chosen because it
was considered a well designed circuit, or because it has a conveniently
high component count?



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