[MrFixr55]

Hi Bob, this is a typical grid Leak detector with feedback, in other words, the Armstrong Regenerative receiver. The only differences are use oof a tetrode and a tuning capacitor as opposed to a variometer. Seems that the white wire is the antenna, black is ground, A- and B-, Red is +2V from a single lead acid cell and the final wire (pinkish?) is B+

My guess after reading the RC10 version of the RCA Receiving tube Manual is that B+ should be 45V. The manual states that plate voltage for a grid leak detector should be 135V through a 250KOhm resistor and a max screen of 45V. Since the screen, B+ lead and one pin of the phone jack are connected together and since by 1930 a 45V B battery existed, it is likely that the B Battery should be 45V. Grid leak should be a 2MOhm resistor and 250pF capacitor. The movable coil controls feedback. This is a simple radio, likely CA 1932 I wonder if it was a Words Airline and how much it sold for.