Chevrolet 1994 Astro Passenger Owner's Manual page 138

BAL (Balance)
The BAL control behind the upper knob moves the sound between the left
and right speakers.
The Lower Knob
Turn the lower knob to choose radio stations.
Tone Levers
Two levers control the tone of your radio.
BASS -Slide this lever up to increase the bass response.
TREBLE -Slide this lever up to increase the treble response.
Adjust this lever to give a pleasing sound. If a station is weak and noisy,
move TREBLE down to reduce the noise.
PWR (Power)
The PWR button turns your system on and off.
Pushbuttons
The four pushbuttons let you return to favorite stations. To set the
pushbuttons, just:
Tune in the station.
Push SET. (SET appears in the VF display for a few seconds.)
Within 5 seconds, push one of the four pushbuttons. Whenever you
push that button, the preset station will return.
NOTE:
Up to three additional stations may be preset by pressing two adjoining
buttons at the same time.
Tune in the station.
Push SET. (SET appears in the VF display for a few seconds.)
Within 5 seconds, push any two adjoining buttons at the same time.
(The station will return when the same two buttons are pressed again.)
Clock
To set the clock, just:
Push SET.
Within 5 seconds, push and hold HRS (time
will
be displayed) until the
correct hour appears.
Push and hold MINS until the correct minute appears.
To display the clock with the ignition off, push the upper knob. The time
will be displayed for a few seconds.
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