TB 9-6625-2163-24
(9) Position jack A15Z1J2 (fig. 2) using mark approximately 10 degrees from
(10) Perform a (1), (2), and (4) above.
(11) If the bandwidth is too broad, rotate the mark on jack A15Z1J2 (fig. 2) slightly
toward mark on jack A15Z1J1 (fig. 2). If bandwidth is too narrow, adjust it slightly away
from mark at A15Z1J1 (fig. 2).
(12) Fasten jack A15Z1J1 (fig. 2) by replacing base plate.
(13) Determine bandwidth as described in a (1), (2), and (4) above. If necessary,
repeat (11) and (12) above.
10. Video Enable Delay and Gating
a. Performance Check
(1) Disconnect cable from RTS oscilloscope CH 1 and DEMOD OUT connector and
connect X10 oscilloscope probe from CH 1 to test point A10TP5 (fig. 2).
(2) Connect second X10 probe (also from RTS kit) from oscilloscope CH 2 to test
point A4TP6 (fig 2).
(3) Press oscilloscope AUTO-SCALE pushbutton and set TIME/DIV switch to 1 s.
Delay from leading edge of second pulse on CH 2 to trailing edge of pulse on CH 1 should
be between 1.6 and 2.0 s; if not, perform b below.
(4) Disconnect oscilloscope CH 1 probe from A10TP5 (fig. 2) and connect to test
point A8TP2 (fig. 2).
(5) Disconnect oscilloscope CH 2 probe from A4TP6 and connect to test point A9TP4
(6) Press oscilloscope AUTO-SCALE pushbutton once again and set TIME/DIV
switch to 2 s. Delay between leading edge of last pulse on CH 1 and trailing edge of pulse
on CH 2 will not exceed 6 s.
b. Adjustments. Adjust test instrument video enable delay control A10R7 (fig. 2)
until delay from leading edge of second pulse on CH 1 to trailing edge of pulse on CH 2 is
1.8 s (R).
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.