Thanks you very much for this "hard to find" service manual.
Will help a lot in repairing this receiver.
Text excerpt from page 19 (click to view)
TROUBLESHOOTING HINTS
1. No Character
No Character
Are the Contrast & Brightness Controls maximum Yes
No
Change the Contrast & Brightness control to maximum
Is whole screen bright? Yes
No
No Raster
Refer to No Raster
Is CRT Cathode (Rk, Gk, Bk) signal level normal? No Is the output signal of the (pin 16,18,20) pre-amp (IC801, TDA9210) normal? No Is 6.3Vdc line normal? Yes Is blanking pulse (pin 20 of IC801) normal? Yes
Yes Rk, Gk, Bk About 40Vpp
Check the peripheral circuit of CRT Board
Yes
Check the video output (IC802, TDA9536) and their ambient circuit
No
Trouble in 6.3Vdc line of the Main PWB
No
Check the blanking pulse circuit
Is input signal normal? Yes Trouble in IC801 and its ambient circuit