Today I fired up my 3577A to begin to do some tests.? It has been sitting in my lab, fully environmentally controlled, for several years unpowered.? It was working perfectly when it was put away.
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Immediately I got a trace memory failure, shows as banks 2 and 6.
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I ran further tests and got failures:
Log sweep signal level test
Log sweep flatness test
Linear sweep signal level test
Linear sweep flatness test
Synthesizer and LO test
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So I checked the power supplies and reference, all look great.? Hmmm, what could be a common cause then?
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I started with the trace memory.? I put in a bunch of sockets and moved around chips.? Indeed two of the 2k x 8 Toshiba RAM chips appear to be bad as the failure follows them to whatever bank I plug them into.
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Anyone else just have these chips die while sitting around unused?
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As I need to order replacements I will have some time to probe around.? Apparently something else has failed just sitting around.
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Any thoughts as to where I should start?
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