TM 11-6625-847-45
4-6. Test Set A2, Dc-to-Dc Converter and Regulator Module A3 Tests
Dc-to-dc converter and regulator module AS (module A3) (fig. 3-10) is in the bank of the test set front panel and is secured to the bottom plate by four captive
screws. The general support test of this module utilizes the test set as test equipment.
a. Test Equipment and Materials.
(1)
Multimeter AN/PSM-6B.
(2)
Oscilloscope AN/USM-140(*).
(3)
Charger, Battery PP-1451/G.
(4)
One each of the following load resistors:
(a) 39 ohms, 25 watts.
(b) 10,000 ohms, 1 watt.
(c) 2,490 ohms, 10 watts.
(d) 8.45 ohms, 10 watts.
(5)
Fabricate the -test cable as shown in figure 4-2.
c. Procedure.
Step
Control settings
No.
Test equipment
Equipment under test
Test procedure
Performance standard
1
AN/PSM4B
Test set A2
a. Set the PP1461/G power
Less than 18 to more than 22
FUNCTION switch:
a. POWER switch: OFF
switch to OFF.
volts dc.
DCV-20KΩ/V
b. SERV SEL switch: OFF
b. Connect a jumper wire be-
RANGE switch: 250
c. PA/RT switch: PA
tween pins 64 and 40 on
d. KEY switch: OFF
connector J1.
e. XMIT STATUS switch: OPR
c. Connect a 39-ohm, 25-watt
f. ALC VOLTAGE INFO
resistor between DC
switch: max ccw OFF
VOLTAGE 20, test con-
g. ALC VOLTAGE TUNE
nector A1J11, and ground
switch: max ccw OFF
pin 38 on J1.
d. Set the power switch on the
i. MC FREQ 10MC switch: 0
PP-1451/G to ON.
MC FREG 1MC switch: 0
e. Set the POWER switch on
MC FREQ .1MC switch: 0
the test set to ON; rotate
j. 600 VDC LOAD switch:
the SERV SEL switch to
LOW
STBY.
k. 2400 VDC LOAD switch: 1
f. Check to see that the test
set POWER indicator is
lighted.
g. Connect AN/PSM-6B across
the 39-ohm load resistor.
h. Rotate the test set DC VOLT-
AGE 20 control from fully
counterclockwise to fully
clockwise.
i. Set the test set POWER switch
to OFF, and disconnect
the 39-ohm load resistor.
2
Same as step 1 above,
Same as step 1 above.
a. Connect a 10,000-ohm, 1-watt
Between -31 to -35 volts dc.
except set RANGE
load resistor between pins
switch to 50.
89 and 70 of J1.
b. Connect the AN/PSM-6B
across the 10,000-ohm load
resistor (observe polarity);
Connect the positive lead of
the AN/PSM-6B to pin
70 on J1, and the negative
lead to pin 39 on J1.
c. Set the POWER switch on
the test set to ON (SERV
SEL switch is still at
STBY).
d. Observe and record the volt-
age reading on the AN/
PSM-6B.
e. Set the POWER switch on
the test et to OFF, and
disconnect the 10,000-ohm
load resistor.
3
Same as step 1 above,
Same as step 1 above.
a. Connect the 2,490-ohm, 10-
Between 115 and 135 volts dc.
except set the ANI
watt load resistor between
PSM-6B RANGE
pins 36 and 70 of J1.
switch to 250.
b. Connect the AN/PSM-6B
across the 2,490-ohm load
resistor.
c. Set the test set POWER
switch to ON. Observe and
record the reading on the
AN/PSM-6B.
d. Set the test set POWER switch
to OFF, and disconnect
the 2,490-ohm load resis-
tor.
4
Adjust the controls
Same as in step 1 above.
a. Connect an 8.45-ohm, 10-
Between 12 and 14 volts, peak-
on the AN/USM-
watt load resistor between
to-peak, square wave.
140(*) for a square
pins 37 and 38 of J1.
wave of approximately
b. Connect the AN/USM-140(*)
15 volts peak to
across the 8.45-ohm load
peak.
resistor.
c. Final-adjust the AN/USM-
140(*) as required for the
performance standard in-
dication.
d. Disconnect all test equipment,
set the test set POWER
switch to OFF, and set
the power switch on the
PP-1451/G to OFF.
4-7
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