User's Manual

Digital UHF Transmitter Chapter 2, System Description and
Customer Remote Connections
DT835A, Rev. 1 2-4
On the UHF exciter tray, switch (S1) is
an Operate/Standby switch that
provides the Operate command
(Enable), when in Operate, to the each
of the amplifier arrays. The Enable to
each amplifier array is split four, five or
six ways and then applied to the UHF
amplifier trays. The Enable is needed to
turn on the switching power supplies
located in the UHF amplifier trays.
When the UHF exciter is in Operate, the
green LED (DS2) is on and when the
exciter is in Standby, the amber LED
(DS1) is on.
NOTE: If the transmitter does not
switch to Operate when S1 is switched
to Operate, check that a dummy jumper
plug, with a jumper between pins 1 and
2, is connected to jack J7 on (A9) the
remote interface assembly in the single
UHF exciter assembly. This jumper
provides the interlock needed for the
operation of the transmitter. If the
interlock is present, the green LED
(DS5) on the transmitter control board
should be lit.
The operation of the transmitter is
controlled by the front panel switches on
the UHF exciter tray. During normal
operation of the transmitter, switch S2
should be in the Auto position. The front
panel of the UHF exciter also has LEDs
that indicate a Modulation Fault (Loss),
red LED (DS9), and a VSWR Cutback,
amber LED (DS7).
2.1.7 Metering Panel
Table 2-2: Metering Panel Meters
METER FUNCTION
Combination meter
(A13)
Displays power in terms of a percentage of the calibrated
transmitter output level on the scale; a full-scale reading is
120%
Switch (S1), meter Selects the desired % Forward, % Reject, or % Reflected
reading.
% Forward (0 - 120 %) Displays the output power level (≈100%)
% Reject (0 - 120 %) Displays the % Reject Output Power (<5%)
% Reflected (0 - 120 %) Displays the % Reflected Output Power (<5%)
Power meter side A
(A15)
Displays power in terms of a percentage of the calibrated
amplifier array output level on the scale; a full-scale reading
is 120%
Switch (S2), meter Selects the desired % Forward or % Reflected reading
Forward (0 - 120 %) Displays the output level of the array (≈ 95%)
% Reflected (0 - 120 %) Displays the % Reflected Output Power of the array (<5%)
Power meter side B
(A16)
Displays power in terms of a percentage of the calibrated
amplifier array output level on the scale; a full-scale reading
is 120%
Switch (S3), meter Selects the desired % Forward or % Reflected reading
Forward (0 - 120 %) Displays the output level of the array (≈ 95%)
% Reflected (0 - 120 %) Displays the % Reflected Output Power of the array (< 5%)