TM 55-1680-351-10
33.
Operational Siting and Operating
Procedures
a.
General. General instructions for correct handling of the
AN/PRC-90 are provided below. Specific instructions are included in
subparagraph b.
(1)
The AN/PRC-90 is normally used as a beacon transmitter
which transmits a continuous, "down-going beeper" AM signal for
approximately 14 hrs. Whenever possible, the radio is placed on a high
point, free of obstructions, and left in the BCN 243.0 mode until search
aircraft or other vehicles approach. The antenna should be vertically
oriented (perpendicular to the search vehicle radio) as shown in figure 9.
(2)
If a search vehicle appears near the operator he may use
one of two voice channels or transmit international Morse Code (MCW) to
communicate with the search vehicle.
(3)
When informed that a firm location has been determined, the
radio can be used to communicate with other crewmen to join forces for
recovery operations.
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