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Products => Test Equipment => Topic started by: Jester on December 04, 2021, 11:19:33 pm

Title: Anybody fix a Keithley 2000 with ac calibration noticeably off?
Post by: Jester on December 04, 2021, 11:19:33 pm
Anybody fix a Keithley 2000 with ac calibration noticeably off?
Title: Re: Anybody fix a Keithley 2000 with ac calibration noticeably off?
Post by: Jay_Diddy_B on December 04, 2021, 11:45:58 pm
Jester,

This is probably the best place to go to get the documentation:

Link: https://xdevs.com/fix/kei2000/ (https://xdevs.com/fix/kei2000/)

This is TiN's website.

The service manual and the schematics are here.

Regards,
Jay_Diddy_B
Title: Re: Anybody fix a Keithley 2000 with ac calibration noticeably off?
Post by: Jester on December 05, 2021, 01:04:21 am
Jay_Diddy_B,

Thanks for the links, I'm sure they will be very helpful.

Real quick look at the schematic looks like there are a lot of jelly bean or readily available parts: DG muxes, LM311, LM339, TLE2081, AD637, OPA177, anything LT

Can anyone tell me if repair parts are generally easy to come by, are there any or many unobtainable parts:  AD705JR?, AD711JR, NE5534, relays, switch, etc?
Title: Re: Anybody fix a Keithley 2000 with ac calibration noticeably off?
Post by: coromonadalix on December 05, 2021, 01:39:24 am
I think they have an network resistor chip, who's hard to get, and got pricey ??   

https://www.eevblog.com/forum/repair/keithley-tf-245-replacement-options-(k2000-models)/ (https://www.eevblog.com/forum/repair/keithley-tf-245-replacement-options-(k2000-models)/)
Title: Re: Anybody fix a Keithley 2000 with ac calibration noticeably off?
Post by: Kleinstein on December 05, 2021, 09:33:55 am
Most parts for the Keithley2000 are still available. The custom resistor network is a bit tricky and expensive, but in this case, with DC still working this should not be the problem. The FPGA/CPLD part could be tricky due to the included code.
The AC part should not have very hard to get parts, though in these times it could even happen that near yellybean parts (e.g. DG408, MCP6001) at times are hard to get in the right case.
For the OPs there is still the option to use substitutes (e.g. for an AD705).