This radio was part of a complex navigation and communication system used on multiple aircraft types.
The RT-793/ASQ is a VHF/UHF transmitter & receiver from 225.00 to 399.95 MHz with 50 kHz spacing. The unit includes a single conversion auxiliary receiver tuned on 243 MHz. The main receiver is a triple conversion with two tunable IFs. The tunable IFs are similar in design to the R-390/URR and R-390A/URR (see below).
The tuning of the receiver is accomplished by means of a motor driven autopositioner. An external control head is used for both frequency selection and all other necessary controls.
This radio seems to be an evolution of the ARC-51. Manufactuting of the ARC-51 started in 1959. The main difference with the ARC-51 is the control head with a BCD output and digital memory.
Below is the 1st and 2nd IF module. It utilizes ferromagnetic slugs for tuning. This design is an evolution of the Collins R-390. Similar design was used on the ARC-54.
Getting it working....
Last update May 7, 2001