[GreenKeys] Plantronics and others

Larry Tighe larryradio at att.net
Thu Nov 11 12:35:24 EST 2010


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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