Not much luck on abpr, so I'll try it here. Got this on ebay just for
the fun of it, pics on binary under whatzitfor. It's a Signal Corps
Frequency Meter type BC-153, 75 to 1500kc. It consists of a large tuning
cap and three coils that are switched in series to get three different
bands, 75-225kc, 200-700kc and 600-1600kc. These form a tank circuit
with a meter in series with the tuning cap and coil. It also has an
adjustable buzzer feeding the top of the tank, and a battery for the
buzzer. I figure you set the buzzer going and pick up the freq you want
with the tuning. Someone has put a dc voltmeter in place of the original
one, probably was an ac ammeter, which shows the internal tank current,
a power indicator probably? There are no external connections except to
add more inductance for a lower resonance. My guess is, this tank
circuit radiated the resonant frequency to be picked up by a receiver,
like a sig gen. Any guesses out there, and what type meter might have
been used? I think this might be early 30's. Any info available? Ken