What does the red button on the top left corner do. Model GEN-1475A

It's the dial light.

Thanks Warren, it must be burned out. Do you happen to know also what the red light labeled "Illumicator" is?
:It's the dial light.
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Used to have the same radio. If I remember right, it's a signal strength indicator.

Thanks again, I just inherited this radio from my grandad. Works good except for the lights. I appreciate the info!

:Used to have the same radio. If I remember right, it's a signal strength indicator.
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