KCS201 - schematic needed/dead tuner

[probnot]

Anyone know where I can find a schematic or service doc for a KCS201 chassis (TV model CX095E)? This is one of those retro-style mid 1970s 9" black and white sets.

As far as I can tell the RF stage in the tuner is dead. When I got it, the VHF tuner was dead (on channels 3 and 4), but UHF was showing the OTA digital noise so it appeared to be working.

Once I brought it inside to test UHF, it worked at first, but as I tuned to a station it would "disappear" after a few seconds. Now it appears both bands are not tuning. I can however modulate a signal on channel 2 and pick it up slightly off frequency, though fine tuning doesn't work. I think this may be because channel 2 is close to the IF frequency (I don't have any equipment that can directly inject an IF signal).

Anyone have any thoughts on where to start on this? I have no doubt this will need some recapping, but I want to get the tuner working before I blindly start replacing stuff.