Mode 4 Challenge Video Adjustment Using AN/UPM-137A

TM 11-6625-667-45/NAVAIR 16-30APM123-2/TO 33A1-3-367-22

Pulse Width

e. Set and adjust AN/UPM-137A oscilloscope

Test Point

Adjust Control

controls as follows:

A1TP1 . . . . . . . . . . .. A101 . . . . . . . . . . . . .. 0.30.01

(1) VERTICAL-CHAN A-AC/DC to DC.

A1TP2 . . . . . . . . . . .. A1R11 . . . . . . . . . . . .. 0.30.01

(2) VERTICAL-CHAN A-75 IN OUT to

A1TP3 . . . . . . . . . . .. A1R14 . . . . . . . . . . . .. 0.30.01

OUT.

A1TP4 . . . . . . . . . . .. A1R17 . . . . . . . . . . . .. 0.70.01

A2TP1 . . . . . . . . . . .. A2R2 . . . . . . . . . . . . .. 2692

(3) VERTICAL-CHAN A-VOLT/DIV to 2.

A2TP2 . . . . . . . . . . .. A2R7 . . . . . . . . . . . . ..12 0.l

(4) DISPLAY/CHAN A/ALT/CHAN B to

A1TP5 . . . . . . . . . . .. A1R22 . . . . . . . . . . . .. 1507.5

ALT.

(5) HORIZONTAL-SYNC to EXT DC -

MARK

5.1-24. Mode 4 Challenge Video Adjustment

( 6 ) CALBIRATORSXTAL

Using AN/TPM-25A

SEC) to.1 & 1.

( 7 ) CALIBRATORS LEVEL to mid-

a. Perform the procedures given in paragraph

position.

5-22a and b.

f. Connect equipment as shown in figure

b. Connect the equipment as shown in figure

5.1-7.1.

5.1-12.

g. Apply power to equipment and permit 15-

c. Set AN/USM-281 DELAYED TIME/DIV

minute warmup.

to 1 SEC, and adjust DELAY DIV to observe

h. Adjust AN/UPM-137A rf signal generator

t h e first pulse of the challenge video on

OUTPUT ATTEN control to -9 dBm minus

oscilloscope A INPUT and the 1 s markers on B

cable attenuation marked on cable connected to

INPUT.

test set PROBE jack.

d. Adjust control A1R32 until the pulse width

Example - 9 dBm minus 0.9 dB is 8.1 dBm

is 0.5 0.1 s.

e. On the transponder test set, set ISLS to ON

i. Continually press and release test set PUSH

Adjust control A1R29 until the spacing between

TO TEST switch and adjust control A1R43 to

the first challenge video pulse and the fifth, isls,

just ACCEPT Indication. Adjust

pulse is 8 0.05 s.

AN/UPM-137A rf signal generator OUTPUT

ATTEN 0-100 dbm to 3 dB less than that in step

5.1-25 Mode 4 Challenge Video Adjustment

Using AN/UPM-137A

j. Connect AN/UPM-137A oscilloscope

a. Perform procedures given in paragraph

VERTICAL-CHAN A-VIDEO IN jack to test set

5.1-23 a through g.

test points listed in chart below. Set test set

b. Connect cable from test set PROBE jack to

PUSH TO TEST switch to LOCK and adjust test

AN/APM-270(V) RF IN jack.

s e t control indicated until performance

c. Connect AN/UPM-137A oscilloscope

requirement is obtained.

V E R T I C A L - C H A N A-VIDEO IN jack to

NOTE

AN/APM-270(V) DET VIDEO jack.

Adjust the AN/UPM-137A

d. Adjust AN/UPM-137A oscilloscope con

oscilloscope controls as necessary to

trols as necessary until first pulse of pulse train is

observe signal.

observed.

e. Adjust control A1R32 until pulse width is

0.5 0.2 s.

f. Set test set ISLS switch to ON and adjust

AN/UPM-137A oscilloscope to observe first five

pulses. Adjust control A1R29 until spacing

between first and fifth pulses is 8 0.15 s.

5.1-33

Change 5