EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: cncjerry on May 24, 2015, 05:06:50 pm
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I picked up a keithley 213 quad voltage source out of curiosity. It's capable of pretty accurate voltage sourcing up to +/- 10v and can be used as an 8192 point voltage step generator as well.
At power on it indicates a 'ram' failure. It uses a socketed common ram chip with battery backup. It also had a rom for programs. I assume the ram lost battery power. The startup checks the ram, rom, and then the ram checksum. If it lost battery backup, I would assume the last test (checksum) would fail. I don't know how they test the ram. The question is if they can detect the ram has failed other than a checksum, I assume they read a known location for valid data? if that is the case replacing the ram and battery won't do any good, correct?
I opened a case on eBay as the seller's picture had only the power light lit indicating a good power on test whereas it fails when I power it on with blinking lights. So I expect to return it unless a new ram (without an image) will fix it.
Any experienced 213 users out there?