RF Technology PA220
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OPERATING INSTRUCTIONS
13. Internal Adjustments
TEMP LED
The temperature (TEMP) LED indicates illuminates should the
amplifier's internal temperature become too high. The RF power is automatically
reduced if the internal temperature rises above safe limits.
1.3 Internal Adjustments
All internal adjustments are factory set and should not need to be changed under normal
conditions. A possible exception to this is the RF output power level which may need to
be changed to comply with local licensing requirements. The low forward power
warning circuit should be set at the same time as the forward power level.
WARNING
Ensure that the power setting complies with the
requirements of your licensing authority. Failure to do
so may result in penalties being imposed by the
licensing authority.
Output Power
The output power is set by RV2. This is nominally set to 100 Watts
(+50dBm), but may be set to any value between 20 and 100 Watts depending upon
local regulations in the destination country. RV2 determines the threshold
affecting the ALC voltage that is fed back to the transmitter module to regulate RF
output power.
RF Level Detector
The forward RF power threshold associated with the RFO LED on
the amplifier front panel is set by RV3. This is nominally set at half to three-
quarters of the preset output power.
1.4 Amplifier I/O Connections
The PA220 has three connectors on the rear panel.
1.4.1
RF Input
The RF drive is delivered via a BNC connector. The absolute maximum power that
should be applied to this connector is 25 Watts.
1.4.2
RF Output
The RF output signal is available from an N-type connector.
