[GreenKeys] Plantronics and others

[Peter Gottlieb]

  They're probably tantalum.

If it were me, I would replace them /all/ with 105 C low ESR 
electrolytics chosen from the Digikey catalog.

Peter


On 11/11/2010 12:35 PM, Larry Tighe wrote:
> HOwdy Folks,
>
> I fired up some Plantronic 1280A modems.  These are big rack mounted units
> and are very similar to the Hal ST8000A's.
>
> Smoke and stench upon turn on.  Those ratty little electrolytic caps that
> look like tan drops of plastic cooked.  They seem to be on the DC inputs to
> the modulator, demodulator and control boards.  I think they're around 22
> mfd and 15 VDC rated.
>
> There was no way to bring up the voltage slowly with a variac as the PS in
> these is either on or off....line voltage low will cause the PS not to put
> out any voltage so I couldn't bring it on slowly.
>
> These little caps are small and thus fit on the boards and allow them to
> slide in and out without hitting boards above and below....
>
> QUESTION:  What are these called and who sells 'em?
>
> Thanks,
> Lar
> K2JIA
>
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