After getting his hands on this relic [Gregory Charvat] handle to hack it, converting the receiver into a transceiver.
It may be old, however the R-390A is nothing to scoff at. It’s capabilities include AM, code, as well as FSK operation from 500 kHz to 32 MHz. however it is a receiver with no method of transmitting on the exact same bands. This is where [Gregory’s] hack comes into play. He rerouted the variable-frequency oscillator feed inside of the R-390A in order to utilize his 20M single-sideband unit. generally what this does is enable him to control whatever from the 390, utilizing the microphone from the SSB — together with some switching hardware — to transmit his own messages.
His demo video starts with him making a few contacts utilizing the hacked equipment. He then spends a long time at the whiteboard explaning the changes. This part went over our heads, however it becomes a lot more clear when he cracks open the situation as well as shows the actual modifications.