[time-nuts] 5070B once more.... (actually electrolytics)

[Robert Atkinson]

I'm not sure if the espionage story is true. However there is a problem with electrolytics. the modern ones have got a lot smaller and run hotter due to incresed PSU switching frequencies. A detailed look at datasheets can be revealing. Many electrolytics have suprisingly short lifes quoted. Some are jus a couple of thousand hours. I did find a small one installed the wrong way round in a piece of HP kit recently. I was in a 8924C comms test set. The keypad was not responding. A low value SM electrolytic in a timing circuit (74ls123 or similar)had obviously beed wrong since new.

Rober G8RPI

--- On Sat, 23/5/09, g4fre at g4fre.com <g4fre at g4fre.com> wrote:

> From: g4fre at g4fre.com <g4fre at g4fre.com>
> Subject: Re: [time-nuts] 5070B once more.... (actually electrolytics)
> To: time-nuts at febo.com
> Date: Saturday, 23 May, 2009, 2:30 PM
> I just got hit by this issue in my
> Dell GX270. Its the one i use for HPIB instruments/Heather.
> The video output disappeared. Doing a web search i found
> lots of posts on they used faulty capacitors. They didnt do
> a recall as it would lead to "bad customer perception of
> Dells quality" (they had just done a battery recall). 
> Upon examination 2 had "bulged" You can get kits to replace
> all 18 electrolytics. It may explain why there are a lot of
> gx260/270/280 unsold on ebay recently 
> Dave 
> 
> 
> > 
> > Message: 5
> > Date: Fri, 22 May 2009 23:01:38 +0000
> > From: Mark Sims <holrum at hotmail.com>
> > Subject: [time-nuts] 5070B once more.... (actually
> 5370A fans)
> > To: <time-nuts at febo.com>
> > Message-ID: <BLU125-W32EB9626ACF899C8949FFCE560 at phx.gbl>
> > Content-Type: text/plain; charset="iso-8859-1" 
> > 
> > Many failed electrolytic caps on PC motherboards and
> in PC power supplies can be traced to a case of industrial
> espionage gone wrong.  Somebody sole the formula for
> the caps from a Japanese company and sold it to a
> competitor.  That competitor allegedly cranked out over
> a billion of the caps and cornered the market with their
> cheap prices.  Unfortunately the formula that was
> stolen was missing a key ingredient...  voila, 
> over a billion capacitors in a zillion PC's...  and
> every one of them is destined to fail.  The failure
> mode is goo oozing out the top of the cap. 
> > ----------------------------------------
> 
> 
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>