NAVAIR 17—2OAX—737
4.5.18 Use the oscilloscope delayed sweep function to expand the portion of the TI signal indicated in
Figure 1, with the oscilloscope delayed time base set for 10 p.s/div. such that the display is similar to Figure
2. Verify that the deviation of the expanded display corresponds to delta time
(st)
=
48.5 p.s ±2.4p.s.
Figure 2. 9960 Hz Deviation (Expanded)
4.5.19 Verify that the electronic counter indicates between 9958.008 and 996 1.992 Hz.
4.5.20 Adjust the TI 9960 FM tone modulation control to UNCAL [fully ccw (0)].
4.5.21 Set the TI 30 Hz tone modulation control to the CAL (UNCAL lamp off) position.
4.5.22 Verify that the electronic counter indicates between 29.994 and 30.006 Hz.
4.5.23 Set the TI 9960 FM tone modulation control to the CAL (UNCAL lamp off) position, the
FREQUENCY MHz switches to 118.000, and the Meter function switch to OFF.
4.5.24 Verify that the electronic counter indicates between 1014.9 and 1025.1 Hz.
4.5.25
If the TI is a NAV—750B, proceed with step 4.5.26. Otherwise, if the TI is not a NAV—750B, skip
to step 4.5.32.
4.5.26 Set the TI FREQUENCY MHz switches to 075.000, and the Meter function and Tone Selector
switch to 400 Hz.
4.5.27 Verify that the electronic counter indicates between 397.2 and 402.8 Hz.
4.5.28 Set the TI meter function and tone selector switch to 1300 Hz.
4.5.29 Verify that the electronic counter indicates between 1290.9 and 1309.1 Hz.
Deviation
13
