User's Manual

300-Watt Digital UHF Transmitter Chapter 5, Detailed Alignment Procedures
DT830A, Rev. 1 5-17
5.4 Output Power Level
Using a forward-calibrated coupler and
an HP power meter, or equivalent,
adjust the output power for a reading of
500 watts out of the bandpass filter on
the true average power meter. Adjust
R28 on (A10) the visual/aural metering
board in the exciter tray for 100% in the
% Forward Output position. The aural
power is not used; set the pots R20 and
R51 on (A10) the visual/ aural metering
board fully CCW.
Turn the power-adjust pot to 20% on the
meter in the Forward Power position.
Reverse the SMA cables on J1 and J3 of
(A7) the visual/aural metering board
(1265-1309) in the exciter tray
assembly. Adjust R39 on the visual/aural
metering board for a 20% reading in the
Reflected Output Power position.
Adjust R22 on the transmitter control
board (1265-1311) in the exciter tray
until the VSWR LED just begins to light
on the exciter front panel. Place the SMA
cables on the visual/aural metering board
in their original positions. The reflected
output power is now calibrated.
This completes the detailed alignment
procedures for the DT830A transmitter. If
a problem occurred during the alignment,
refer to the detailed alignment
procedures for that tray for more
information.