Mostly OT: Looking for Manual/Schematic for Wavetek 1901C

[Josh Dersch]

Snagged a Wavetek 1901C last week.  This is a 12" oscilloscope display 
(X/Y+intensity input), I was hoping to use it as a point-plotting/vector 
display for a couple of little computer projects of mine.  (Or maybe 
just hooking an Asteroids board up to it... :). It's in pretty good 
shape (has more screen burn than I think I've ever seen in a few spots, 
though.)  I fixed a couple of cold solder joints and it's now mostly 
working, except something appears to be going slightly wrong in the Y 
deflection or amplification (it's getting clipped/distorted depending on 
the gain and input intensity).

Anyone have a service manual or schematic for this thing or know good 
sources for such things?

Thanks as always...
Josh