[Milsurplus] airborne radio activity

[Cletus W Whitaker]

de WB2CPN South Central Pennsylvania   2002.07.01

Dave is right, the 522's were not duplex.  They put two 522's in tandem.
An added squelch relay (BK-35) in the receiver in one box was used to key
the transmitter in a second box.  Audio was coupled across in the usual
transformer fashion.  There were a few reasons for repeaters; the 522 was
used on the ground (J-Pole antenna) by FAC's, but a main reason was the
restriction on frequencies the usual VHF airplane could use. Only four
channels, no more.  (Some key airplanes had more than one 522 in order to
have eight VHF channels. Reason, what with one channel being tied up for DF,
two for ATC, and various organizational frequencies, and the increase in 
airplanes and use of VHF, it became difficult to have one channel that all
airplanes who were being shot at could use.  Maybe an old pilot will confirm
that just about all the communications between the bombers and the P-47's
and P-51's in the early days was done by hand signals and flares. 
                      73  Clete