Table 35: Possible Faults In The Mobile Antenna Installation - Codan Envoy Reference Manual

I
NSTALLATION
M
OBILE STATIONS
Connecting the antenna to the transceiver
A vehicle antenna is a tuned antenna, and therefore, must be connected to the
transceiver using 50 Ω coaxial cable. Type RG58 cable is normally used. The cable
should be as far as possible from other vehicle wiring, especially high-voltage ignition
wiring.
In addition to an RF coaxial cable connection, an automatic tuning whip antenna also
requires a control cable to be connected to the transceiver.
The cables are supplied in standard lengths with the appropriate connectors fitted at
either end.
Earthing the antenna
For information on earthing a mobile antenna, see the documentation provided with
the antenna.
Tuning a mobile antenna
A mobile antenna uses an automatic tuner to make the physically small whip appear
larger to the transceiver.
To tune a mobile antenna:
1
Troubleshooting the mobile antenna
Common problems caused by incorrect installation are listed in
WARNING: Before using the antenna system see the safety information provided.
WARNING: Poor installation can damage the antenna beyond repair.

Table 35: Possible faults in the mobile antenna installation

Symptom
Antenna tunes when
stationary, but fails
when mobile
400
Scroll to the channel on which you want to transmit, then press PTT to tune.
Possible cause
Incorrect positioning of
the antenna on the vehicle
Action
Ensure correct installation and tuning procedures
are followed.
With an SWR meter in place, alter the position of
the antenna to achieve best forward-radiated
power.
Carry out all testing in the open, away from trees
and buildings etc. Leaning the antenna away from
the bodywork sometimes assists in tuning. Check
that the problem does not move to other channels.
E ™ T
NVOY
Table 35.
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RANSCEIVER EFERENCE ANUAL