Codan NGT 2010 RF Technical & Service Manual page 557

Adjusting the external high-power amplifier
NOTE
NOTE
NOTE
To adjust the external high-power amplifier:
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NGT Transceiver System Technical Service Manual
Ensure the dummy load and power meter are rated to 1 kW PEP (500 W
CW).
The transceiver must be in Service mode to perform this adjustment (see
page 154, Accessing Service
The output power is factory-set, so it is not likely to be outside the
specified limits. Check that there are no faults with the transmitter circuits
before attempting to adjust the power output.
Connect setup as per page 180, Adjusting high output
set to 100 W output (Links X2 and X3 open on drawing
output is greater than 100 W PEP on a frequency below 10 MHz, solder Link X2 as
per drawing 08-05910 (sheet
Select test channel 25.
Set the ALC ADJUST control on the High-power ALC Adaptor PCB fully
counterclockwise (minimum power).
Hold down PTT and note the output power.
Turn the ALC ADJUST control slowly in a clockwise direction until the required
output power is reached (see
The indicated PEP level with two-tone modulation depends on the type of
measuring instrument, as shown in
Check that the two-tone waveform is clean and undistorted.
If it is not clean and undistorted, further analysis is required.
Release PTT.
High power—Fault finding and adjustments
mode).
1)).
Table 17 on page 240).
Table 17 on page
power, ensuring the NGT is
08-05416 or, if the power
240.
243