Optimus STA-7500 - Problem Solving

PROBLEM SOLVING
If you receiver is not working as it should, the following suggestions might help you. If you follow the sug-
gestions in this chart and the receiver still does not work properly, contact your local Radio Shack store
for assistance.
No power (all indicators are off). Press POWER.
Be sure the power cord is plugged in.
Try a different AC outlet.
Check the fuse.
If you are listening to an audio source other
than the tape deck, be sure TAPE MON is not
lit. If necessary, press TAPE MONITOR so the
indicator goes off.
Check the volume level.
Check the SPEAKER buttons. If you connect
only one pair of speakers, press only the cor-
responding SPEAKER button.
Check the audio source connections. Be sure
you have selected the correct audio source.
Check the speaker connections.
If the PROTECTION indicator comes on, a
built-in protection circuit has turned off the
amplifier. Press POWER to turn off the receiver.
Then: y
— Be sure the speakers are correctly connected.
Be sure there are no stray wire strands touch-
ing other wire strands or metal objects.
— Be sure the receiver is adequately ventilated.
— Be sure the speakers have an impedance of 8
to 16 ohms.
Low-pitched humming on AM. Move the power cord away from the AM
antenna connection wires.
If there is a TV near the receiver, turn it off or
move the receiver away from the TV.
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