Service switch - small, round opening in the rear cabinet near the Video inputs or the antenna jack (typically early-90's), push and hold while turning the power on - or if there is no service switch on the rear of the TV use the remote control and press within one second of each other:

[PWR OFF] - [DISP], [5], [VOL+], [PWR ON]

-or-

[PWR OFF] - [DISP], [5], [PWR ON]

-or-

[PWR OFF] - [DISP], [5], [VOL+], [PICTURE], [PWR ON]

The TV will turn on in service mode.

You may need to set the television into 'tuner' mode (instead of Video-1, etc.) before performing the service mode button sequence.

NAVIGATE IN SERVICE MODE
[1] = Moves to Previous Menu Item
[4] = Moves to Next Menu Item
[3] = Adjusts Value Up
[6] = Adjusts Value Down
[MTS] = Toggles Stereo/Mono Audio


SAVE NEW SETTING
[MUTE] followed by [ENTER] to store NEW setting to NVRAM
RESTORE USER SETTINGS
[8],[ENTER] = Restores All *USER* setting to Factory Defaults
RESET VALUES
[0],[ENTER] = Read Default Value from Stored Settings (Reset)
LEAVE SERVICE MODE
[PWR OFF] = Leave Service Mode any settings not written will be in effect until TV is unplugged or a Reset is performed.RETURN TO DEFAULT SETTINGS:

• BEFORE storing NEW settings - unplug TV from wall, wait a few seconds, then plug back in, turn TV set on - All settings not written will have been lost.
• AFTER storing NEW settings - restore original value from list you made of original values before adjustments and store in NVRAM.