General Instrument DSR-4800 Operating Manual page 37

Front Panel Controls and Menu Display
Display (EXT 2) Menu 1, Edit Option 1
,
The default video pattern is color bars at 1.0 vp-p. Use the blank
area to turn on/off the color bar pattern. Note this will interrupt
the receiver's current video output until the user turns off the test
signal.
Display (EXT 2) Menu 1, Edit Option 2
,
The default audio signal is 1KHz tone +18 dBm. Use the blank
area to turn the tone on/off for primary.
Note this will interrupt the receiver's current audio output until
the user turns off the test signal.
Display (EXT 2) Menu 1, Edit Option 3
,
The default audio signal is 1KHz tone +18 dBm. Use the blank
area to turn the tone on/off for secondary.
Note this will interrupt the receiver's current audio output until
the user turns off the test signal.
Display (EXT 2) Menu 1, Edit Option 4
,
Currently unused test mode.
29 DSR-4800 Operating Manual