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"David Farber" <farberbear.unspam@aol.com>: Apr 05 09:12AM -0700 Jeff Liebermann wrote: > to be bad contacts in the switch. However, that doesn't sound like > anything that might produce the symptoms you're seeing.   > When in doubt, replace everything.   Hi Jeff,   Was I supposed to use one channel of the scope to monitor the power button line and then monitor the PS_ON line with the other channel, and then see the delay time between the two?   My customer picked up the unit quite a while ago and has had no complaints... so far.   Thanks for your reply. -- David Farber Los Osos, CA

"David Farber" <farberbear.unspam@aol.com>: Apr 05 09:05AM -0700 David Farber wrote: > out of thin air. The fact that they now put it in writing probably > means that less people can do the math now than 40 years ago.   > Thanks for your reply.   I did order a replacement eBay MOSFET and it didn't help. Now that I've just read the S.E.R. thread about "Fake Chips," maybe that didn't prove anything!   -- David Farber Los Osos, CA

bitrex <bitrex@de.lete.earthlink.net>: Apr 05 11:56AM -0400 > getting it back together is risky, but then it isn't working now, so not > that much to lose.   > Jon   Thanks for the reply. The original LCD was very old, and it literally crumbled in my hands as I attempted to disassemble it from the board to clean the contacts.   Fortunately, I managed to find a lot of 3 unlit LCD displays on eBay that look like drop in replacements for the original - they use the same SMT OEM Hitachi display controller in a similar package, and even the PCB layout is very similar. The date code on the original board looks like 1986, these are from the early 1990s.   $3 plus shipping for the lot. Seems like a much easier solution...:)   --     ----Android NewsGroup Reader---- http://usenet.sinaapp.com/

etpm@whidbey.com: Apr 04 11:35AM -0700 While looking for some 18650 batteries on eBay I came across some 4000, 5000, and even one seller offering 6000 MAH ones. I'm pretty sure that even a 4000 MAH claim is exaggeration. Looking online I see that there are all sorts of Chinese companies that buy cells from other vendors and just add their own wrapping with false specs printed on them. With all the emphasis eBay puts on money back guarantees and other buyer protection I wonder why they allow such obvious fake claims. I know that eBay can't police all the items being sold to make sure the claims are accurate. But something as common and obviously fake I would think eBay would stop allowing to be sold on their site. Eric

Jon Elson <jmelson@wustl.edu>: Apr 04 01:44PM -0500 > sure the claims are accurate. But something as common and obviously > fake I would think eBay would stop allowing to be sold on their site. > Eric Would the average "vapor smoker" know the difference between a 1 AH and 6 AH battery? (Well, the latter would last longer, but how would he quatify that?)   A guy I'm working with is making some lighted clothing and using lots of 18650s. It seems that not all 18650's are even the SAME SIZE, which seems hard to believe, as the part number IS the size in mm!! Geez, how hard can THAT be? Maybe the last time they tried to measure one, the caliper got welded across the cell and somebody got hurt.   I'm scared to death that once the cells get a little worn, they will start catching fire in his garment things. Yes, he ONLY uses eBay batteries, even though I warned him.   Jon

mike <ham789@netzero.net>: Apr 04 02:18PM -0700 > sure the claims are accurate. But something as common and obviously > fake I would think eBay would stop allowing to be sold on their site. > Eric   Ebay will stop allowing when doing so would result in greater profit for EBAY.

Cursitor Doom <curd@notformail.com>: Apr 04 10:33PM On Mon, 04 Apr 2016 11:35:50 -0700, etpm wrote:   > eBay can't police all the items being sold to make sure the claims are > accurate. But something as common and obviously fake I would think eBay > would stop allowing to be sold on their site. Eric   I stopped buying batteries off Ebay some time ago. Too many fakes. You used to be able to tell them with their poor quality printing and spelling mistakes but they seem to have overcome that nowadays so It's bloody near impossible to tell until you put them into service and they leak, go open circuit or catch fire.

Jeff Liebermann <jeffl@cruzio.com>: Apr 04 04:49PM -0700 >While looking for some 18650 batteries on eBay I came across some >4000, 5000, and even one seller offering 6000 MAH ones. I'm pretty >sure that even a 4000 MAH claim is exaggeration.   Worse. I ran them through a West Mountain Radio CBA II discharge tester:   This is a new Ultrafire 3000 ma-hr cell at a 1300 ma constant current discharge (which is approximately what the flashlight was drawing): <http://802.11junk.com/jeffl/LiPo/Ultrafire%20LiPo%203000%20ma-hr%2018650.jpg> About 800 ma-hr capacity. I've seen a few of the "fire" type cells deliver 1200 ma-hr, but most are like the one above. Garbage.   Note the high tech battery holder and connection enhancer: <http://802.11junk.com/jeffl/LiPo/Ultrafire%2018650%20test.jpg>   More: <http://lygte-info.dk/review/batteries2012/Common18650CurvesAll%20UK.html> <http://lygte-info.dk/review/batteries2012/Common18650IndividualTest%20UK.html> At 1A discharger rate, most of the cells tested were around 2500 ma-hr.   >that there are all sorts of Chinese companies that buy cells from >other vendors and just add their own wrapping with false specs printed >on them.   Yep. They pay extra for the larger ma-hr numbers.   >sure the claims are accurate. But something as common and obviously >fake I would think eBay would stop allowing to be sold on their site. >Eric   Caveat Emptor. If the batteries actually met the stated specifications, they would be seriously dangerous if shorted. Think of this as a "safety feature".   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: Apr 04 04:56PM -0700 On Mon, 04 Apr 2016 13:44:28 -0500, Jon Elson <jmelson@wustl.edu> wrote:   >hard to believe, as the part number IS the size in mm!! Geez, how hard can >THAT be? Maybe the last time they tried to measure one, the caliper got >welded across the cell and somebody got hurt.   There's more differences than just the dimensions: <http://www.lygte-info.dk/info/Battery%20button%20or%20flat%20UK.html> Button top or flat top? Cells with built in protection circuitry are about 1.5mm longer: <http://g02.s.alicdn.com/kf/HTB1Qz2yHpXXXXX7XXXXq6xXFXXXd/200158439/HTB1Qz2yHpXXXXX7XXXXq6xXFXXXd.jpg>       -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jon Elson <elson@pico-systems.com>: Apr 04 12:15PM -0500 frank wrote:     > in my experience with fake parts, they usually have nothing to share > with the real one. Well, I bought some "Xilinx" 9500-series CPLDs from a Chinese outfit, when I got stuck with a batch of boards and the chip was no longer available.   They mostly worked. I think that they were untested die. A small number, about 5 - 10% would not accept the configuration - they were totally dead. If they did configure, they worked fine.   Well, I don't KNOW these were fake, but the fact that I'd never had more than one Xilinx part ever come up totally dead, lead me to suspect they were. I have no idea whether these were reject wafers, or somebody got hold of the masks and made a batch.   Oh, actually, there was one other detail that pointed to fake. There was no molded-in pin 1 dimple on the chip. All Xilinx parts did have the dimple.   Jon

Jon Elson <jmelson@wustl.edu>: Apr 04 01:47PM -0500 Tim Schwartz wrote:   > just don't meet spec or work at all, and we have no way of knowing. > They think they are being good businessmen by getting money for their > scrap. Ah, yes, the Darkness-Emitting Arsenide Diode, or "DEAD". Seems that was an April 1st story in a respected electronics trade mag, quite some years ago. It was a way to get 100% yield out of the foundry!   But, the above scenario was the genesis of Poly-Paks, about 40 years ago. Floor sweepings, and YOU get to test them!   Jon

"jfeng@my-deja.com" <jfeng@my-deja.com>: Apr 04 12:04PM -0700 On Monday, April 4, 2016 at 11:46:49 AM UTC-7, Jon Elson wrote: > April 1st story in a respected electronics trade mag, quite some years ago. > It was a way to get 100% yield out of the foundry! > Jon I remember seeing the data sheet for the DED in the early 1970s. I think it was from Litronix, but it could have been either Signetics or Monsanto.

"jfeng@my-deja.com" <jfeng@my-deja.com>: Apr 04 12:42PM -0700 > I remember seeing the data sheet for the DED in the early 1970s. I think > it was from Litronix, but it could have been either Signetics or Monsanto. The one from Signetics was the Write-Only memory http://repeater-builder.com/molotora/gontor/25120-bw.pdf

Chuck <chuck@mydeja.net>: Apr 04 03:16PM -0500 On Sun, 3 Apr 2016 23:25:16 -0000 (UTC), Cursitor Doom >but if mine burn up at say 1.3A, is that a clear indication that they're >fake?   >Your thoughts, gentlemen.... Back in the late 90s there was a company called Surburban Electronics that sold fake STR regulators that didn't regulate and supposedly the switching transistors used in Sony tvs. The fake transistors set on fire in under a second. Still don't understand why it was worth counterfeiting such cheap parts.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

John-Del <ohger1s@aol.com>: Apr 04 03:53PM -0700 On Monday, April 4, 2016 at 4:16:31 PM UTC-4, Chuck wrote:   > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus   Suburban still exists IIRC, I just don't buy from them unless it's an obsolete flyback or something obscure.   I will buy cheap ICs if they're current production but sell in small quantities, such as LED controllers and such. Some devices I would hope are just not worth the trouble to counterfeit. Simple three legged devices like transistors, IGBT, mosfets etc are too easy to counterfeit that I won't buy them generically unless I simply cannot source them from a reputable supplier.   Speaking of Sony, how many MCZ3001 smps controller chips have you seen destroy parts as soon as power is applied? The only reliable source I know of is B&D Electronics. Supposedly, Electronica also has reliable MCZ3001 chips but since these TVs are pretty much gone, it's no longer a big deal.

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