(following on from the discussion of leaky DIP sockets)
I could really do with an instrument which measures down at the picoamp level or lower. The Keithley 610C seems to be highly regarded around here, but they very rarely come up for sale here in the UK. Keithley's equivalent current model, the 6517B, is $8K, and from what I hear Keithley's build quality isn't what it once was...
There is one used 610C on eBay, not working, in the US for about $100. Anybody have any experience of repairing these things? I found a sevice manual online, they don't look particularly difficult to work on, but I'm guessing one of the the most common faults is blown input transistors which are a matched pair on a module, only available from Keithley.
Any advice? For $100 I'm tempted to take a gamble and have it delivered to our US office, one of our guys can bring it over next time he visits. OTOH if the parts are unobtainium I'll wait for a working one to appear.
TIA