I think mine is actually just a plain CTC-120 also, the SAMS just happens to be labelled A, perhaps it just covers some later revisions or something, although it doesn't even list my GJR641 in the 47 models it
does list on the front page. Go figure.
The diagram pasted inside my cabinet says CTC-117/118/120
This SAMS covers a whole swack of models. For example, it includes at least 5 different tuner setups, 3 different ones with the LED display on the front, the one that uses the OSD and includes the clock and at least one mechanical tuner.
L201 Quadrature (13.6uH) part #143834
U201 part #153684 crosses to:
ECG: ECG1175
NTE: NTE1175
GE: GE-1175
RCA: SK3212/1175
Workman: WEP2175/1175
Zenith: 221-Z9056
An ex of mine once picked up a similar chassis, portable, mechanical-tuner model at a garage sale for a few dollars because the sound didn't work, thinking at worst we'd be using it directly off of a VCR to get remote capability and had a small stereo with aux input right there anyway. When I pulled the back and twisted the adjustment marked Audio IF or somesuch about 1/8 turn the sound came up perfectly.
That TV worked like a charm for years...