TM 11-6625-2946-14/TM 08168A-14/1
Section IV. PERFORMANCE TESTS
5-8. Power Input Circuit Performance Test
5-7. General
The procedures contained in this section provide step-
s. Test Equipment and Materials.
(1) Power Supply PP-3940/G
by-step instructions for the testing of the test set to deter-
(2) Digital Voltmeter AN/USM-451
mine its serviceability prior to its return to, or to confirm
b. Test Connections and Conditions. Connect the
or isolate the faults reported by the using activity. Com-
power supply 0-30 VDC output cable to the 24 VDC
ply with the instructions preceding each table prior to
EXT connector on the test set.
performing the procedures contained within the table.
c. Procedure. Perform the procedures as described in
Perform each step in the sequence listed. Do not vary the
sequence. For each step, perform all the actions required
in the Control settings columns; then perform each pro-
cedure step, verifying the results against the correspond-
ing performance standard.
Table 5-3. Power Input Circuit Performance Test
Control settings
Performance
Test
Test
Equipment
Step
standard
procedure
under test
no.
equipment
a. None
POWER: EXT a. Adjust power supply COARSE ADJ and FINE ADJ controls for read
1
PP-3940/G
ing of + 32 vdc on its voltmeter
COARSE ADJ : fully ccw
b. + 14 0.5 vdc
b. Using digital voltmeter, measure voltage across test set + and
ON/OFF switch: ON
RADIO connectors.
AN/USh4-451
c. None
c. Readjust power supply for a voltmeter reading of + 19 vdc.
elector switch: 100 DC
d. +14 0.5 vdc
volts
d. Repeat step b.
e. 7.0 div. ap-
e. Momentarily hold test set FUNCTION switch in BAT position and
proximately
observe test set meter reading.
a. None
Same as step 1
POWER: EXT a. Turn off power supply, disconnect cable from 24 VDC EXT connector
2
on test set and 0-30 VDC output on power supply. Using clip leads or
locally fabricated cable, connect between power supply 0-30 VDC output
and test set + and BATTERY input connectors.
b. None
b. Adjust power supply COARSE ADJ and FINE ADJ controls for a
reading of + 14 vdc on its voltmeter.
c. + 14 0.5 vdc
c. Using digital voltmeter, measure voltage across test set + and
RADIO connectors.
d. Approx-
d. Momentarily hold test set FUNCTION switch in BAT position and
imately 7.0 div.
observe test set meter reading.
e. None
e. Readjust power supply for a reading of + 12 vdc on its voltmeter.
f. 12 0.5 vdc
f. Using digital voltmeter, measure across test set + and - RADIO
connectors.
g. 5 0.5 div.
g. Momentarily hold test set FUNCTION switch in BAT position and
observe test set meter reading.
h. None
h. Readjust power supply for a reading of + 7 vdc on its voltmeter.
i. 7 0.5 vdc
i. Repeat step f.
j. Less than 1
j. Repeat step g.
div.
C.
Procedure. Perform the procedures as described in
5 - 9 . RF Power Detection and Metering Cir-
cult Performance Tests (with Power
Amplifier)
5-10. RF Power Detection and Metering
a. Test Equipment and Materials.
Circuit Performance Test (without Power
(1) RF Signal Generator SG-1144(V)1 /U
Amplifier)
(2) Power Amplifier, Boonton 230A
a. Test Equipment and Materials.
(3) Wattmeter AN/URM-182
(1) Power Supply PP-3940/G
(4) Power Supply PP-3940/G
(2) Radio Set AN/PRC-68
b. Test Connections and Conditions. Connect equip-
(3) Wattmeter AN/URM-182
ment as shown in figure 5-4. Set power supply voltage to
24 vdc.
5-12
