Greetings all,

a question for anyone familiar with the Tektronix 7000 series scopes:

I recently acquired one of these equipped with a 7A24 & 7A12 dual
trace amps plus a 7B53A timebase. The scope powers up with readout but
doesn't show a trace, even with signal input. The trigger blinkenlight
on the timebase doesn't budge (I assume it's supposed to).

Compressing the trace using the beam finder, I found a stationary
blinking (at high time/div settings) spot way off to the right. I can
shift it vertically with the trace amp's position knobs, but that's
it. No trace.

I've got the service manual here and the power supply checks out ok.
The calibration and troubleshooting and procedures didn't help.

I suspect the timebase is trashed and should be replaced. Before I do
that, and since I'm not inclined to invest a significant sum into such
an old scope (despite the praises that have been sung about it in this
newsgroup), I'd like to hear your opinions. If the mainframe's at
fault, I'd probably just sell it off for parts.

Thanks for your time,

--Roland