Figure 25. Radio Set AN/TRC-68, power control, schematic diagram.
Section V. CONTROL AND FREQUENCY SELECTION CIRCUITS
b. Energizing Tr Relays.
82. Push-to-Talk Circuit
(1) Tr relay K601 is energized by
26.4 volts from Dynamotor DY-
a. General. The rt unit functions as a
151/U (AN/VRC-24) or PP-1494
receiver in standby operation. When the
(AN/TRC-68) when NOR-BB switch
push-to-talk switch of Microphone M-29A/
S801 is in the NOR position. The
U (RT-323/VRC-24) or Handset H-33/PT
push-to-talk switch completes the
(RT-441/TRC-68) is pressed, or when a
ground circuit to relay K6-1 and
a retransmit ground is supplied from the
the relay operates.
AN/GRC-3 through -8 equipment, the rt
unit functions as a transmitter. The push-
(2) Tr relay K601 can be operated from
to-talk circuit receives 26.4 volts dc from
Radio Set Control C-1439/U only
the broadband encoder supply when NOR-
when radio-interphone s w i t c h
BB switch S801 is on the BB position.
S1504 is on the RAD or RAD-INT