Hi Eric,
R167 has 4v4 o both sides
R166 has 3v4 on left and 0v on right
R179 has 6v4 both ends
R178 has 10v9 leftt and 11v on right.
Regards....................Al
hi Al,
That R166 right shouldnt be 0V.
Look at the attached dwg, the RED line should not be at 0v, its throwing the Y plate amps right out of balance. Thats why the trace is off the screen.
Look at the BLUE boxes. Lift one end of the following components out of the pcb.
C253/R266 and C254/R267. that will isolate the top Y push/pull amplfier from the bottom Y amp.
After you have done that you may get a trace, if you adjust the Y shift.
Repeat all the voltage checks 1 thru 10 and the R166/R167 voltages.
Ideally you want to finish up with the 9/10 Y plates at the same voltage.
Lets know what you find.
EDIT:
If that dosnt fix the problem, then check R171/R173. if either of these is open circuit then that voltage on R166 will be 0V.
TR253 could be base to emitter short circuit.
I know its a pain, but I cant see over your shoulder, these are the tests I would do myself..
EDIT2:
As a quick check, measure R171 [1K5] if thats o/c the base of TR253 would be 0V.
These edits are as I keep analysing the dwg, its fuzzy.