Hi! Long time lurker, first time poster. A guy in the neighborhood passed away a while ago. He was a radio host, repairer and I guess station owner. I was invited in a day before his widow was having a huge garage sale to get rid of all his equipment. I didn’t know what this was, but I liked the case. If I had to guess, it was a preamp or some kind of headphone amp? She didn’t know either and just told me to take it. Just curious what it really is...
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Take a close-up picture of number 1. Photo near the circuit board and transistors, axial capacitors.
Read the labels on transistors and capacitors.
It can be a two-channel control sound amplifier.
Front level control and power button.
Behind the input and output jacks of the left and right channels. Black - fuse holders.
Read the labels on transistors and capacitors.
It can be a two-channel control sound amplifier.
Front level control and power button.
Behind the input and output jacks of the left and right channels. Black - fuse holders.
It looks like about a 20W/ch DIY stereo power amplifier with line level inputs and a volume control for good measure. The 'phone jacks are most likely the speaker output connectors and the RCA connectors would be line level signal input sockets.
Being from a radio station, Id suggest it was a studio monitor amplifier for general purpose use but that would likely mean an FM station for stereo, back whenever.
It's old - probably 1970s by the look of the parts and style but you can't be certain with DIY, as Junkbox parts are often recycled. You'd want to check the caps before applying power for safety reasons. With the addition of a simple preamp that provides more controls, like balance and maybe tone controls and input selection, it could sound just fine, depending on the original design and condition of what's there. There are unlikely to be any more protective devices in the power amplifiers so be sure not to short outputs, overdrive it etc. or it will be worth even less than what you paid for it 😉
Being from a radio station, Id suggest it was a studio monitor amplifier for general purpose use but that would likely mean an FM station for stereo, back whenever.
It's old - probably 1970s by the look of the parts and style but you can't be certain with DIY, as Junkbox parts are often recycled. You'd want to check the caps before applying power for safety reasons. With the addition of a simple preamp that provides more controls, like balance and maybe tone controls and input selection, it could sound just fine, depending on the original design and condition of what's there. There are unlikely to be any more protective devices in the power amplifiers so be sure not to short outputs, overdrive it etc. or it will be worth even less than what you paid for it 😉
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I wonder if its some kind of 70 volt speaker type of amp and that is what the transformers are, perhaps the amp running off 12 volts. It looks very old... germanium outputs?