A while back I bought a slew of old serial boxes on the cheap and I have been using them for inexpensive project boxes. I figured I show a recent project where two more of them were repurposed for another life.
Over the past week I've used to build a vintage station control system to interface my boat anchor receivers and transmitters.
The design objective was to provide a means to select one of four transmitters and receivers (in any combination) and to provide mic audio, CW keying, PTT control and receiver muting. PTT control includes sensing the CW PTT from the AEA Keyer, which provides an adjustable semi break-in PTT control line, mike PTT or a footswitch. CW keying can be set for either grid or cathode keying depending on how the interface cable is wired. The transmitter box controls the transfer of the mike audio, cw keying and PTT control.
The receiver box allows for relay receiver muting, or for positive or negative 28 VDC audio muting (aka 75a4, NC303 and the modified HQ-150.) It also interfaces with the CW sidetone from the AEA keyer (which can be used with hand keys) by relay switch audio transfer between the RX earphone jack (manually selected plug in cable) and the headphone jack on the RX box. The 28 VDC muting power supply is floating, and is keyed via an opto-isolator for almost instantaneous muting control.
There's a huge pile of cables that had to be wired up for interfacing to the various rigs.
T/R antenna transfer is via a Johnson electronic TR switch.
Pete
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