TB 9-6625-2163
11. Video Reply and Comparison Pulse Width
a. Performance Check
(1) Disconnect oscilloscope probes from test points A8TP2 and A9TP4 (fig. 2).
Connect CH 1 probe to test point A11TP1 (fig. 2).
(2) Set oscilloscope TIME/DIV switch to 100 ns, TRIGGER SOURCE to CH 1,
and adjust HORIZONTAL POSITION control to position pulse on CH 1 for a pulse width
measurement. If video pulse width is not between 0.65 and 0.7 s, perform b(1) below.
(3) Disconnect oscilloscope CH 1 probe from test point A11TP1 (fig. 2) and connect it
to A11TP2 (fig. 2). If width of comparison pulse is not between 0.49 and 0.51 s, perform
b(2) below.
NOTE
When visual accuracy of oscilloscopes timing is questionable
(as in the paragraph above and subsequent paragraphs), use
oscilloscope width measurement or cursor function to obtain
required accuracy.
b. Adjustments
(1) Adjust control A11R6 (fig. 2) until pulse width is 0.675 s (R).
(2) Adjust control A11R15 (fig. 2) until pulse width is 0.5 s (R).
a. Performance Check
(1) Disconnect oscilloscope CH 1 probe from test point A11TP2 (fig. 2) and connect it
to test point A11TP1 (fig. 2).
(2) Connect oscilloscope CH 2 probe to test point A11TP2 (fig. 2).
(3) Set FUNCTION switch to I/P and press PUSH TO TEST switch and turn to
LOCK position.
(4) Set RTS INTERROGATOR Menu 3 REPLY SIGNAL to ID OF POS.
(5) Perform a power measurement on RTS. Stop measurement after reading has
been obtained.
(6) Press oscilloscope AUTO-SCALE pushbutton and set TIME/DIV switch to
and ACCEPT lamp will glow.
(7) Set TIME/DIV switch to 500 ns and adjust HORIZONTAL POSITION control
to reference C1 pulses on CH 1 and CH 2 to center graticule line on display. If pulse on
CH 2 is not centered within pulse on CH 1, perform b(1).
