TM11-5895-846-14
(10) Place the SHF MONITOR channel
(5) Adjust the OUTPUT LEVEL control
selector switch in each of the channel positions, one
(A2AT2) fully clockwise.
channel at a time, and adjust AT2 for the corresponding
(6) Adjust AT1 on the SHF output assembly
channel on the Al module to obtain an indication of 8 on
A6 to obtain an indication of 180 milliwatts on the SHF
the SHF MONITOR meter.
MONITOR meter.
c. Adjustments to Perform when SHF Drive
f. Fault Threshold Adjustment.
Assembly A2 is Replaced.
(1) Connect a modem and upconverter to one
of the SHF CHANNEL COMBINER CH INPUTS on the
(1) Check that the output level adjustment
amplifier/mixer and set them up for normal operation.
A2AT1 is fully clockwise and the gain adjustment A2AT1
(2) Set the SHF MONITOR meter switch to
the X1 position and the SHF MONITOR channel selector
(2) Place the SHF MONITOR switch to the
to SHF OUT and adjust A2AT2 for a 9.6 milliwatt
X10 position.
indication on the SHF MONITOR meter.
(3) Place the SHF MONITOR channel
(3) Observe the FAULT lamp. If the FAULT
selector switch to the SHF OUT position.
lamp is on, adjust A4R3 until the lamp goes off. If not
(4) Connect
all
the
SHF
CHANNEL
possible to accomplish the adjustment, replace the A5
COMBINER cables to the proper channel input
module and repeat this procedure.
connectors.
(4) With the FAULT lamp off, adjust A4R3
(5) Adjust AT1 on the SHF drive assembly A2
until the FAULT lamp comes on.
to obtain the correct output power reading.
(It is
(5) Adjust A2AT2 for a 12 milliwatt indication
assumed 180 mw is the correct reading unless otherwise
on the SHF MONITOR meter and observe that the
specified.)
d. Adjustments to Perform when the FET/TWT
FAULT lamp is off.
(6) If the FAULT lamp is not off, reattempt to
Assembly A3 is Replaced. This procedure is the same
obtain a normal indication by repeating steps (2) through
as for step c above. Repeat steps (1) through (5) above.
(5) above. If a normal indication cannot be obtained,
e. Adjustments to Perform When SHF Output
replace the A5 module and repeat this procedure.
Assembly A6 is Replaced.
(7) If the FAULT lamp is off, set the SHF
(1) Check that the variable attenuator AT1 on
MONITOR meter switch to the X10 position and adjust
the Al SHF channel combiner is adjusted fully clockwise
A2AT2 for a 160 milliwatt indication on the SHF
MONITOR meter.
(2) Place the SHF MONITOR switch to the
5-37. Removal and Replacement of Amplifier/Mixer
X10 position.
(3) Place the SHF MONITOR channel
Modules
selector switch to the SHF OUT position.
a. Removal and Replacement of SHF Combiner
(4) Connect
all
the
SHF
CHANNEL
COMBINER cables to the proper channel input
connectors.
5-58