Initial Test Procedures Using AN/UPM-137A

TM 11-6625-667-45/NAVAIR 16-30APM123-2/TO 33A1-367-22

Control

Position

result should be 1,090 1 MHz. If it is not, adjust

FUNCTION . . . . . . . . . . . . . . SYSTEM

the AN/URM-64 until it is.

MODE . . . . . . . . . . . . . . . . . . 1

g. Connect the output of the MD-796 as shown

CODE(A, B, CA D) . . . . . . . . . . 0000

in figure 7-1.

ISLS . . . . . . . . . . . . . . . . . . . . OFF

h. Set the AN/USM-281 controls as follows

PUSH TO TEST . . . . . . . . . . . Released

DIR/RAD . . . . . . . . . . . . . . . . RAD

POWER: ON

Sweep Display Switch: Delayed

c. Set and adjust AN/UPM-137A rf signal gen-

Delayed TIME/DIV; 5

erator as indicated below:

Man TIME/DIV; 10sec

Control

Position

Sweep MODE AUTO

-6 dbm

OUTPUT ATTEN 0-100 dbm

MAIN SLOPE:

TRANSMITTER-XMTR

DELAYED SLOPE: -

FREE . . . . . . . . . . . . . . . . . XTAL

DIV DELAY: .02

TRANSMITTER-CW

Main Trigger Source Switch: EXT.

SOURCE . . . . . . . . . . . . . . . EXT 1090 MHz

DISPLAY: A

e. Set AN/UPM-137A Interrogator Signal

A VOLT/DIV: 5

A POLARITY: + UP

Simulator TRANSMITTER-XMTR FREQ to XTAL.

A Input Coupling Switch: AC

e. Set and adjust AN/UPM-137A SIS generator

i. Connect the rest of the equipment as shown in

as indicated below;

figure 7-1.

Control

Position

SIF 1 CODER-FUNCTION

j. PresS and lock and test set PRESS TO TEST

SEA. . . . . . . . . . . . . . . . . . . N

switch; set the MODE switch to 1, CODE switch to

SIF 1 CODER-CODE ... ... . 0000

7777 and FUNCTION switch to SYSTEM.

SIF 1 CODER-WIDTH ADJ . . Approx. center

k. Set the controls of the AN/UPM-98 SIF

SIF 1 CODER-SUBST PULSE

CODER unit as follows:

SEL. . . . . . . . . . . . . . . . . . . OFF

CODE: 7777

MIXED VIDEO-MIXED VID

FUNCTION: N

SEL.. . . . . . . . . . . . . . . . . . SIP 1

SUB PULSE SELECT: Cl

PRF-RANGE MULT . . . . . . . EXT.

SUB PULSE POSITON: O

TRIGGERS-DELAY TRIG

LEVEL: HI

(SEC)-DLY RANGE

PULSE WIDTH: 0.45

MuLT . . . . . . . . . . . . . . . . . X4

TRIGGERS-DELAY TRIG

/. Connect oscilloscope CHANNEL A to A8TP2

(SEC)-MULT1-11. . . . . . . 6.0

and observe the detected video. Adjust the

7-4. Receiver

Frequency

and

AN/UPM-98 AMPLITUDE control for a convenient

Bandwidth

amplitude of pulse.

NOTE

m. Connect the oscilloscope CHANNEL A to test

When the AN/URM-64 frequency is

point A4TP5 and CHANNEL A to A8TP6.

changed, the POWER SET meter of the

n. Set the AN/UPM-98 XTAL MARK SYNC con-

AN/URM-64 should be reset to 0.

trols as indicated below:

Connect the equipment as shown in figure 7-1. Set

Control

Position

and adjust the controls as described in paragraph

SYNC SELECT . . . . . . . . . . . . -EXT.

SUP . . . . . . . . . . . . . . . . . . . . MAXIMUM CCW

7-3.1.

TRIGGER DELAY . . . . . . . . . To the point where the first

a. Decrease the AN/URM-64 rf output with the

pulse at oscilloscope CHAN-

ATTENUATOR control until the teat set barely in-

NEL A is delayad 5 micro-

dicates ACCEPT and then increase the

seconds from the leading

AN/URM-64 rf output 3 dB.

edge of the second puke at

CHANNEL B.

b. Use the AN/URM-64 SIGNAL FREQUENCY

control to decrease the frequency until the test set

7-3.2. Initial Test Procedures Using

barely indicates ACCEPT. Use the AN/USM-207

AN/UPM-137A

a n d the CM-77A/USM to determine the

a. Use AN/UPM-137A to make connections

AN/URM-64 output frequency. Note this fre-

shown in figure 7-1.l.

quency.

b. Set and adjust test set controls as indicated be-

c. Reconnect the AN/URM-64 to the MD-796.

low:

Increase the AN/URM-64 frequency until the test

7-2 Change 4