I was at a local small airport today and spied a large radio sitting behind the counter. It turns out to be a topic of great interest. The radio has been handed down for decades there and the manual has long since disappeared.
This thing is a Comco model 779 AM transceiver that is on the local airport frequency. Comco is short for Communications Company and they were in Coral Gables, FL, before being bought out by E.F. Johnson.
The poor radio has seen better days, but considering its age, its in pretty decent condition. A couple of the protective coverings over the lamps are broken and all three lamps do not light. The mic is intermittent when keyed (and the mic connector is loose, which is more than a clue). We did hear an aircraft in the area, so the receiver works, but tx usefulness is unknown.
I opened the top and looked in, assuming it was a tube radio. Didn't see any tubes when looking in, or much of anything. It seemed to be mounted under a shield and I didn't dig too deeply into it.
Appears to have a receiver module and a transmitter module. The receiver module has printing on the plate for four channels, but no knob. Therefore single receive (which is perfectly fine in this case).
The transmitter module is more interesting. It has a switch with the following labels: AOC, R-1M, T-1M, T-2M, PA, A-12, A-24.
I can only guess at them-
- PA: Public Address or Power Amplifier.
- R-1M: Might be remote control.
- T-1M and T-2M: Two transmit channels perhaps?
- A-12/A-24 and AOC: No idea. A-12 and A-24 seem to hint at perhaps a voltage level, but at the transmitter switch? That makes no sense.
Has anyone heard of Comco before or might have information (or ideally the manual) for the 779?
I have found a few other unrelated Comco things on the Internet, but they're of no use (mobile unit or VHF/UHF FM).