Becker Designed AR 3201 - Manual (Page 30)

3.11 Precautions
In order to secure a reliable transceiver operation, please note the following precautions:
a) Before running-up the engines, ensure that the transceiver is switched off.
b) Always conduct a verbal pre-flight check. Note that in the vicinity of a flight control, a broken or
shorted antenna cable must not necessarily impair the function. At a distance of 5-10 km from the
ground station, however, the connection will doubtlessly fail.
c) Transceiver communication contact should always be conducted using a clear, loud voice and by
speaking directly into the microphone. Otherwise, cabin background noise could predominate,
making the message inaudible.
d) Use suitable microphones or headset for aircraft only. With certain aircraft types (wood or fibre-glass
aircraft, gliders and helicopters) the signals transmitted by the unit’s antenna may be picked up
and enhanced by the integrated microphone amplifier (feed back). As a result, the signal received
by the flight control will be superimposed by whistles and/or strong distortion. This phenomenon
may not necessarily remain constant for all channels.
e) The PTT button of the microphone or control unit might jam, causing the system to remain in the
transmission mode. In order to rule such cases out, please ensure that the arrow in the frequency
display (from serial no. 4000 onwards) illuminates during the transmission mode, and extinguishes
when the PTT button is released.
AR 3201 - ( )
Page 3-6 DV 28110.03/04 Issue 02/92