Thanks you very much for this "hard to find" service manual.
Will help a lot in repairing this receiver.
Text excerpt from page 8 (click to view)
1-8
Setting the TV system default
1) Press <SYSTEM MENU> on the Remote Control to enter the User Preference Manual (UPM). 2) From the User Preference Manual on the TV screen, select TV SYSTEM to change the TV system default accordingly as shown in the table below:
Version /21R /21S /22S /30S /33S /37S
Region Region 3 Region 4 Region 2 Region 4 Region 3 Region 1
TV system default AUTO NTSC PAL AUTO AUTO NTSC
3) Press <SYSTEM MENU> on the Remote control to exit.