[sdiy] Beckman Industrial 9060 'scope woes - no luck finding service manual

[aankrom]

I have a Beckman Industrial 9060 'scope that has problems. When first 
turned on, it does not function. At first I thought it was just a high 
voltage portion getting old and it needed to warm up. But then I noticed 
that the "trigger" light doesn't come on when a signal is sent through 
it. Sometimes turning it on and off several times will show a brief 
trace and the "trigger" light lights briefly. Sometimes fiddling with 
the time-division/delay knob (the big one) will bring the trace fading 
into view. Sometimes leaving it on will stabilize it. Sometimes I have 
to come back in and fiddle with it.

My problem is I can't find a repair manual for it. Someone once told me 
this model wasn't actually made by Beckman. Also construction is very 
dense inside and repair would be near futile if I didn't know what I was 
looking for. My guess is some oscillator doesn't want to oscillate and 
I'm also curious if it's a power supply issue. Having it sit in a humid 
basement can't have helped so I'm trying turning it on every day to see 
if it will work itself out (fat chance). My guess is a bad capacitor 
somewhere.

I don't need the scope to be precise, I just need it to show a trace 
and obvious signs of 2nd & 3rd harmonics in a sine wave to test gear in 
conjunction with my Wavetek 182A Function Generator.

Anyone know who actually built these units and know of a place where I 
might find a repair manual? Or if anyone has experience with this or 
similar units could give me tips, that'd be great.

My guess is a low voltage power supply has a bad electrolytic cap. 
somewhere...

Maybe I'll try spraying Deoxid in random but calculated places and see 
what that does... Heh.

It's a pretty good scope otherwise: dual-trace, delayed sweep.

AA