TB 9-4920-456-24
(8) Adjust the oscilloscope controls as required to verify that the three reply pulses
have the following characteristics:
(a) Pulse amplitude between 3 and 5 V p.
(b) Pulse width between 0.3 and 0.7 s.
(c) Risetime of 0.1 s or less.
(d) Falltime of 0.25 s or less.
(e) Pulse spacing between 1.7 and 1.9 s.
(9) On radar test set, select menu CHALLENGES (highlighted) and press
pushbutton to M4: WORD B (highlighted). Press TI pushbutton CODE SEL key on MODE
4 keyboard to select word B (B light on, A light off).
(10) Adjust oscilloscope controls to verify three reply pulses on oscilloscope display.
(11) On calibration test fixture, move test cable from REPLY jack and connect cable
to DISPARITY jack.
(12) On radar test set, select menu CHALLENGES (highlighted) and press
pushbutton to M4: NORM to DISP (highlighted).
(13) On oscilloscope display, disparity pulse will appear and frequency counter will
indicate between 186 and 206 s.
NOTE
If frequency counter does not indicate any count or a stable
reading, adjust INPUT A and INPUT B TRIGGER LEVEL
for stable indication.
(14) Adjust oscilloscope controls as required to measure the disparity pulse for the
following characteristics below:
(a) Pulse amplitude between 3 and 5 V p.
(b) Pulse width between 0.35 and 0.95 s.
(c) Risetime of 0.15 s or less.
(d) Falltime of 0.5 s or less.
(15) Observe SLS (highlighted) indicator on TI MODE 4 keyboard. On radar test
set, press pushbutton S5: OFF (highlighted). SLS indicator light will go off.
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