The old 7613 died. The power supply has a problem and I suspect
something is shorted somewhere. So I ran across a 7603 on craigslist
cheap, but with no plugins. So I figured there ya go, I don't have
much use for mesh type storage anyway, in fact I think it was pretty
much a waste of time, at least for my purposes.

So I figured there might be trouble when I got there, I expected to
see a spot in or near the center of the screen but it was not. There
was deflection without plugins, but at least it's not shorted out.

So I plug my plugins in ( care to rephrase that anyone ? ) and instead
of a flat trace in the absence of vertical input I have a sawtooth.
Changing the timebase only affects the trace slightly, through most
ranges it is showing one cycle, only the slope changes. It seems
obvious that the vertical deflection is polluted by the horizontal
deflection, and without the plugins it was deflected by power supply
ripple.

I downloaded the print from bama (the mirror site actually) and it is
a typical Tektronix manual. Like I really needed a refresher on how a
UJT works LOL. Of course it's useful in a sense but it doesn't really
point me in any meaningful direction. Soon I am going to have to go
hands on and just start taking the thing apart. Looking at the print I
have suspects but don't know where anything is.

The point is I'd like to get in and out of this thing. I want the
covers back on and it working without staying apart on the bench for a
week. I am fairly sure it's going to be a filter either in the power
supply or just after it somewhere. Could probably find it quick enough
with a scope..... should I break out the old B&K ?

Mainly I'm looking for some pointers to make this a bit more painless.
I wouldn't mind having the 7613 back up and running but this will do
just fine. In fact, once this is up and running I wonder if anyone
might be interested in the parts from the 7613. I don't even want to
speculate on the price of the CRT, which is strong and burn free BTW.
I'm thinking though for the furture alot of the 7613 parts should fit
the 7603, or am I wrong about that ?

Any help or advice will be highly appreciated.

J