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BARRETT 4075 LINEAR AMPLIFIER - OPERATING & INSTALLATION MANUAL
The antenna and feeders need to be in good condition, and where an ATU is
fitted, the antenna and counterpoise must be adequate. The performance of
the system relies entirely on the condition of the antenna.
A simple test to prove transmitter performance is to use the “Tune” function of
the Transceiver:
•
Tap and hold “Tune” on the front panel of the 4050 Transceiver and note
the readings of the forward power and VSWR displayed on the 4075 Lin-
page 8). This should be performed for each of the
programmed frequencies.
•
If an ATU is fitted and “Tune” is tapped, the system will invoke a tune
cycle. Once the ATU has attained a tune pass, additional “Tune” tapping
will produce the same results as above.
If Selcall is enabled, send a Selcall to ensure the correct modulation to achieve
full output power indication.
Note: As the Transceiver’s antenna type has been set to “4075 Linear Amplifier“, if
an external through-line power meter is used to measure the RF power out of the
4050 Transceiver, the Transceiver will NOT produce 125 W output power. A meas
-
ured reading between 50 W and 80 W is likely to be present at the antenna output
of the Transceiver, when “Tune” is invoked.
Maintenance
This unit requires low maintenance. Regular attention to the condition of all
eternal cables and connections is recommended, especially where the cables
are exposed to unfavourable weather conditions.
