My origninal AM pushbutton radio doesn't play. I had removed it from the car some time ago because it didn't work and now I'm trying to repair it. I took the covers and faceplate off and cleaned all the mechanical tuner parts with contact cleaner/lube and all the mechanicals including presets work correctly.
I setup a test bench with the original AM antenae hooked up, a 10 OHM speaker attached, and a battery charger alligator clipped in for power. When the radio is turned on I just get a low hum from the speaker which does not vary when the tuner or volume controls are adjusted. After the radio is on for 10-15 seconds a small amount of smoke starts coming from inside the radio.
Any suggestions on what is usually wrong with these things? I bought another one on Ebay and it has the exact same low hum but no smoke.
Can I buy or find online a repair manual or schematic?
'67 Camaro Z21