TDS320 will not power off

[jpirok]

So, I just got my hands on a nice looking Tektronix TDS320 this weekend.  When I plug it in it just starts right up, but when I press the Power/Standby button, I get no response.  Everything else I've poked at on it has worked fine.  I can't find schematics on Tek's website and wondered if anyone else had experienced this?

Thanks in advance!

[Ushiwaka]

Crack it open and check that button. It might be broken.

[xwarp]

Word of advice for you, look through some of the search results as shown by clicking the link below:

https://www.google.com/search?q=tektronix+tds+capacitors&ie=utf-8&oe=utf-8

Next, I would expect something going on with the front panel and the touch switches. My TDS460 had issues with the buttons not working properly and it turned out that in addition to a leaky cap on the front panel board, there was a trace dissolved on it.

ALSO.... be VERY CAREFUL on the traces for those bezel switch traces. Alcohol will wipe them right off. I made the mistake of using 100% IPA and it wiped them right off. Did not much matter at that point because one trace had already been damaged previously. I cured the problem by replacing the carbon traces with conductive epoxy.

[John Crighton]

ALSO.... be VERY CAREFUL on the traces for those bezel switch traces. Alcohol will wipe them right off. I made the mistake of using 100% IPA and it wiped them right off. Did not much matter at that point because one trace had already been damaged previously. I cured the problem by replacing the carbon traces with conductive epoxy.

Hello xwarp,
I made the same mistake, used isopropyl on a cotton bud and the little golden zig zag dissappered.
May I have some details on how you repaired the traces with conductive epoxy?
Thanks,
John

[james_s]

I had to repair a damaged trace on the flex in a TDS410, I used some carbon paint that was sold for shielding inside electric guitars. Those flex boards are fragile, in the service manual it warns to not even touch the contacts.

[Smoky]

I can confidently say that I've been inside of a TDS scope once or twice

I found the fault for buttons not working being caused by "glazing" over the carbon contacts embedded in the flexible rubber gasket that surrounds the CRT.

I wash the black contacts with lacquer thinner and lightly wipe off the trace "impression" from the surface with a small piece of 2000 grit 3M wet/dry sandpaper while it's still soaked.

It seemed to work every time I tried it.