TM 11-6625-1633-45
c. Set controls of the AN/URM-149 as follows:
dicated in the following chart and make the adjustments
(1) POWER OFF toggle
on (up)
shown to obtain maximum indications on the wattmeter;
switch:
make each adjustment in incremental steps.
(2) MODULATION selector
cw
switch:
(3) ATTENUATOR
-10 dbm
NOTE
Repeat each set of prior adjustments be
MICROVOLTS/-DBM
fore proceeding to the next adjustment, to
control:
obtain the maximum power output
(4) Center frequency selector
600
throughout the entire frequency range.
handwheel:
Center frequency
Adjustment
Wattmeter
d. Turn on the TS-186D/UP and allow a minimum 2
selector handwheel (MHz)
potentiometer
indication
hour warmup period before proceeding.
600
600 MC (A4R3)
maximum
e. Calibrate the TS-186D/UP by turning the IND
1000
1000 MC (A4R6)
maximum
switch to each of its positions.
1850
1850 MC (A4R19)
maximum
f. Compare the meter indications with those listed in
1100
1100 MC (A4R8)
maximum
the following chart:
m. Perform the klystron beam current adjustment and
IND SWITCH position
Meter indication
repeat the procedure outlined in l above.
BEAT IND
.8 - .9
through the ranges listed in the chart below.
DET
.2 - .4
o. Set the ATTENUATOR control as required for
XTAL
.02 - .05
wattmeter indications, but not more than - 7 dbm and
HET OSC
.6 - .95
make the tracking adjustments indicated for maximum
wattmeter indication.
g. Make certain that the IND switch is in the HET
OSC position.
Center frequency
h. Determine the dial setting corresponding to the
selector handwheel
Adjustment
Wattmeter
600 MHz reading and set the TUNING DIAL and as-
range (MHz)
potentiometer
indication
sembly accordingly; refer to the calibration manual.
725 to 850
800 MC (A4R5)
maximum
i. Put on the headset.
850 to 975
900 MC (A4R10)
maximum
j. Adjust the volume control until the background
1200 to 1350
1250 MC (A4R13)
maximum
1350 to 1460
1400 MC (A4R14)
maximum
noise is at a comfortable listening level.
1460 to 1550
1500 MC (A4R15)
maximum
k. Adjust the TUNING DIAL for zero beat in the vi-
1550 to 1720
1600 MC (A4R16)
maximum
cinity of the setting determined in f above.
p. Repeat the procedure outlined in l through o above
NOTE
until no further adjustments are required.
q. Set POWER OFF toggle switch to OFF position
Frequency meter zero beat must be
and disconnect the test equipment.
observed between 597 and 603 MHz.
5-9. RF Output Frequency Test
l. Repeat the procedure outlined in e and f above at
each frequency indicated in the chart below, making
certain not to move the TUNING DIAL.
b. Set Frequency Meter TS-186D/U controls as fol-
lows:
600-1850 MC
FREQUENCY METER
FREQUENCY MC
REQUIRED ZERO BEAT LIMITS
(1) POWER switch:
ON
counter
MINIMUM (MHz)
MAXIMUM (MHz)
(2) IND switch:
BEAT IND
600
597
603
700
697.9
702.1
800
796.6
802.4
(3) XTAL CAL:
ON
900
897.3
902.7
1000
997
1005
(4) VOLUME control:
Max ccw
1100
1096.7
1103.3
1200
1196.4
1203.6
(5) HET Osc:
ON
5-3
