Continued Airworthiness - Becker AR6201 Installation And Operation Manual

Problem
Speaker output is not
working.
The noise suppression
function of the squelch
is not working.
Receiver noise is always
present.
The display shows a
warning or failure
message
(LOW BATT, STUCK PTT, TX
HOT, FAILURE)
The Antenna VSWR exceeds
3:1.

2.13 Continued Airworthiness

The AR6201-(X0X) maintenance is defined as "on condition" only. No
scheduled or regular maintenance of this product is required.
To verify the frequency accuracy of the AR6201-(X0X) it is recommended
to perform a respective calibration test after 7 years.
DV 14300.03/.04 Issue 5 5/2013
AR6201-(X0X)
Possible Reason
Speaker is switched "OFF" Switch speaker "ON".
Some avionic (especially
non ETSO/TSO approved
avionic) is producing
quite high
electromagnetic
interference, possibly
received by AR6201-(X0X).
Refer to chapter 3.14.
Possibly caused by an
defective or
insufficient
counterpoise for the
antenna.
The impedance of the
antenna cable deviates
significantly from 50
Ohm.
Possibly caused by an
fault on the BNC
connectors of the
antenna cable.
Proposed Solution
Refer chapter 2.8.5.(Page:
CONFIG and MIKE TYPE) and the
explanation about /MIKE_SW in
chapter 2.4.2.
Reduce the interference
emitted by the avionic
around by improving
shielding, distance or
grounding.
Try to suppress the
interference by
adjusting the squelch to
a higher value.
Refer to chapter 3.13.2.
Note, that a higher
value causes a reduced
sensitivity.
Refer to chapter 3.14.
Check for sufficient
size of the
counterpoise and make
sure there is no
mechanical defect on
the antenna.
Make sure the used
antenna cable has 50 Ω
impedance and the cable
is not pinched or
kinked on its way from
the radio to the
antenna.
Check for proper
crimp/solder work on
the BNC connectors and
rectify as far as
necessary.
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