[Milsurplus] BC-9

[Hubert Miller]

What was the rollout year for the BC-9, was it '21 or '22 ?
Then I wonder when the SCR-131 types appeared. I have the manual, but IIR it's a later edition, not the first. 
I would guess the "end year" for the later loop sets was maybe '42. I would guess they were used for training 
shortly into the start of the war, as expedient, but then set aside as the new, actual war radios came off the 
production lines. 
-H