[time-nuts] Seeking HP 3561A schematic diagrams - thank you

Charles Steinmetz csteinmetz at yandex.com
Wed Feb 17 17:29:07 EST 2016

I want to thank everyone who provided helpful comments regarding the 
sick HP3561A, both on and off the list.  Special thanks also to a 
list member who made PDFs of V1 and V2 of the service manual 
available.  As it turns out, the only fault I have found so far was 
fixed before we received the schematics -- a very leaky filter 
capacitor in the off-line DC supply.  I'm about halfway through a 
complete calibration and everything is well within spec so far.

About test equipment quality and reliability:  Frankly, I think it is 
remarkable that a piece of test gear this complex has survived nearly 
30 years needing nothing more than one filter capacitor to meet spec 
(yes, I replaced the pair).  (I'm anticipating that nothing further 
will need adjustment during the remainder of the calibration, which I 
think is very likely.)

Thanks again,


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