You are right, David, but I am still trying to figure out why they add a three tubes BFO to the circuit.

Comment

Comment by Alex R. Whitaker on November 29, 2022 at 8:17pm

Someone added the BFO so that they could receive CW (radio telegraph) or SSB (single side band, supressed carrier) signals, probably in the amateur radio service. The radio wasn't worth much of anything at the time, so it was pressed into amateur, or at least listening in on amateur, radio.