[time-nuts] EIP545A 18GHz counter query

[Chris Wilson]

> Chris,

> Put a ohmmeter across any of the capacitors on the GPIB board and see what
> the resistance is.  Since that kills the unit, I suspect the resistance is
> low (?shorted tantalum) or there is a problem with one of the chips that
> takes the 5 VDC buss down.  Make sure of the polarity of your DMM, + to +
> and - to ground.

> Alternatively, there is a short on the +5 VDC line at the connector on the
> mother board that is 'actuated' by plugging the board in.  Measure the
> resistance to ground of the +5 VDC buss (power off) with the GPIB board
> plugged in and not plugged in.

> Joe


Thanks again Joe, checked the tants on the GPIB board and they seem
fine, have put this aside until the rest is AOK. Then I'll pull the
chips one by one and try and isolate the issue.  The 5 v bus seems
good with the board in or out, too.






29/11/2012 09:27



-- 
       Best Regards,
                   Chris Wilson.