HP6632B repair - cap on ADC

[artag]

I had a problem on a 6632 psu : the volts/amps meters always read close to zero. Tracked it down to a faulty AD677 ADC and have fixed it - but there was a small capacitor soldered across the input pins, and I damaged it.

I think it's a standard production mod, but the digital board isn't in the service manual so the mod probably isn't in a service update either.

Anybody know what the value should be ?

[artag]

I made an approximate measurement on another supply. If anyone else needs this info, the answer is 'about 100pF'.

[SeanB]

Sounds around the right value to solve a RF pickup issue that probably was causing voltage instability with a cellphone near the unit in operation.