Mike, KK5F, produced an extensive 50 page rundown on the subject back in early 2015, entitled "U.S. Military Aircraft Radio Sets Using Receivers Based On Aircraft Radio Corporation Model D Design". This exhaustive report also covered the similar RU/GF sets made for the Navy. The short version is that the SCR-183/283 system originally sprang from the 1930 Aircraft Radio Corporation Model D receiver, and had a slew of additions and updates before the last SCR-AS-183 (14v) and BC-AR-283 (28v) contracts were signed in 1942. The changes through the 1930s are detailed in the document. I've attached it to Steve's copy of this e-mail.

You should be glad you don't have one of the earlier SCR -183/283 sets - the VT-52 triodes are extremely expensive (when you can find one) due to its popularity in high end audio amplifiers. The VT-25s are less so.

- Mike KC4TOS

On 11/12/2021 12:35 PM, Steve WD8DAS via ARC5 wrote:

At an Ohio hamfest I bought a beautiful BC-AO-430 transmitter in black wrinkle finish (from W8AU). It appears from my online research this rig was part of the SCR-183/283 system, and based on the design I'm guessing those were an earlier aircraft radio system before the SCR-274N or ARC-5 command-set systems. Is that correct?

I have the manual and schematics from my online browsing but so far I've not come across any history of the system. Can anyone point me to such resources?

Thank you...