Becker Designed AR 3201 operation manual Testing after installation Ground testing with engine OFF

AR 3201 - ( )

2.6Testing after installation

2.6.1Ground testing with engine OFF

After installing the transceiver, measure antenna matching between antenna base and antenna feeder by means of a VHF reflection meter (voltage/standing-wave meter).

Over the complete frequency range of the transceiver, the voltage/standing-wave ratio must be within the value 3 : 1. Exceeding this value is an indication of mismatch, which can be due to a wrong or inadequate counterweight.

After antenna measurement, carry out a voice test with the ground station.

2.6.2Ground testing with engine ON

With the engine running make sure that the aircraft voltage is within the permissible tolerances at approx. 14 V. Make the test at engine cruising speed. Carry out speech test at a long distance away from the ground station. At engine cruising speed the cabin noise of the aircraft must only be heard muted thus making for clear, intelligible conversation. Hold microphone close to lips when speaking. Switch on intercommunications by means of the IC switch (when provided) and carry out speech test at engine cruising speed.

If necessary, correct volume by means of IC control (see Fig. 2-7).

Apply squelch switch and check squelch function. The squelch threshold can be set from without by means of the squelch control.

CAUTION

In speaker operation no acoustic feedback should occur via the sidetone. If necessary, turn down sidetone by means of the SIDETONE control.

Fig. 2-7 Location of IC control

Page 2-8 DV 28110.03/.04 Issue 04/92