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Beware "fake" parts!

75.101.88.14
Posted on January 10, 2011 at 10:13:58
GP49
Audiophile

Posts: 382
Location: No Cal
Joined: April 21, 2009



This was posted on another board and I thought it worth just a quickie reminder here.

For those who rebuild and upgrade their amplifiers: reports continue to surface about small parts...mainly capacitors...being faked by some el-cheapo manufacturers. Chinese origin is suspected.

This is in addition to the well-known story about the Chinese buying a stolen formula for the electrolyte in electrolytic capacitors but getting an incomplete formula...the capacitors would deteriorate and fail in a short time.

Take a look at these capacitors. The outer can says 6800uf/50V but they are actually 2200uF/35V on the inside. Insufficient capacitance at least; and a blow-up if used in a 40V power supply where you might have thought you had a sufficient safety margin!!





GP49

 

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RE: Beware "fake" parts!, posted on January 10, 2011 at 16:39:04
xaudiomanx
Audiophile

Posts: 3647
Joined: August 16, 2004
 Only issue is how are we to know the real deal from the fake? The Chinese are doing a great job of selling to the Americans. Their prices are extremely good and some of their kits are hard to beat.

 

RE: Beware "fake" parts!, posted on January 10, 2011 at 16:49:19
GP49
Audiophile

Posts: 382
Location: No Cal
Joined: April 21, 2009
 "Only issue is how are we to know the real deal from the fake? The Chinese are doing a great job of selling to the Americans. Their prices are extremely good and some of their kits are hard to beat..."


I assume you mean other than standing back, turning on the power and being ready to shout, "THAR SHE BLOWS!"

One way with this particular example is to tap the can and see if it sounds hollow. That will work until the Dishonest Capacitor Joint Venture and Bottle Cap Factory figures it out and stuffs the empty space with wadded-up toilet paper.

GP49

 

RE: Beware "fake" parts!, posted on January 11, 2011 at 07:48:55
xaudiomanx
Audiophile

Posts: 3647
Joined: August 16, 2004
 I see your point but after installing them it is way too late. The idea is to take the particualr manufacturer to task and put the word out the best you can. How did you find this out anyway? I know the capacitance can be measured but as far as the voltage capability, other than like you said, "turning it on," there is really no way to tell. I am very surprised our government allows for this type of scam, unless they are closing their eyes or not aware. After all they are involved with everything else, including what we are supposed to eat. We do a lot of horse trading with China so it would appear that they would try and make sure they do the right thing.

Paul

 

RE: Beware "fake" parts!, posted on January 11, 2011 at 08:25:47
GP49
Audiophile

Posts: 382
Location: No Cal
Joined: April 21, 2009
 I saw it at another discussion group, and posted it as a favor to the membership here.

We, as hobbyists dealing with this kind of part on a one-by-one basis, are not as much "exposed" as the OEM manufacturer who buys this crap by the case and loads it up into his board-stuffing machine. The prior, well-documented example of the capacitors with the faulty electrolyte includes tales of many consumer and industrial products which used the bad capacitors. The example I am most familiar with is their use in a popular line of LCD computer monitors. A major technology firm serving clients in the oil industry re-equipped several of their facilities with these LCD monitors. This amounted to hundreds, perhaps over a thousand of them. Over time, about a third have failed and more are failing every day.

Where we can run across this, is when the excess production of parts gets surplussed or sold to retailers. For my parts, I often frequent a local store selling electronic surplus, and often run across bins of "no-name" parts of which I know nothing.

GP49

 

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