It's probably sickness, but one day I was thinking that having multiple KEI 2001's and 2002 ain't enough, and wanted to have some addition
to not so convinient Agilent 34970A at work, so I randomly bidded on abused Keithley 2000 from Israel
, with a hope that somebody else would buy it.
As usually, Merphy gotcha me, so I won it with my single bid for $80USD. Meter arrived packaged nicely in big box, powers on and exactly as described.
VFD is intact, desprite missing front face plastic. I will use my donor 2001 front panel later, so not a problem here.
Functions are pretty much broken, shows overflow on ACV,ACI,4W, ramps readings like crazy on DCV,DCI,ohms.
Cranked it open, aha....
Pesky capacitors leaked their electrolyte causing major disaster on poor PCB.
According to date codes, this meter is already 20 year old
It fails pretty much almost every self-test
So no wonder, one of power supply rails probably gone bad.
Will see how this worklog will go.
Did I got another endless repair project, or this baby will be up and running in no time?
Bonus included, for Keithley 2000 our chinese friends from bbs.38hot.net forums reverse-engineered schematics for analog part.
I got it mirrored on my site here
And as usual, all my data and photos are always available on related project page here
In worst case I got very well aged LM399 voltage reference, ha-ha
Gang switch desoldered, can measure voltages,resistances if connected to R115 input resistor and AGND.
Relay, power seem to be ok.
6800uF 16V need to be replaced
17V zener VR109 require replacement (SOT23-3 device), currently use pair of 11+6.2V zeners
AD706 need replace?
Errors in 40x series tests.
Chassis need some metalwork to fix bending
Almost in calibration, even after all that butchery
Article & docsxDevs.com Repair log for Keithley Model 2000 , ?? radiokot.ru
- for russian folks Documentation section about Keithley 2000jhzyou 126.com from bbs.38hot.net schematics