TB 9-6625-096-50
NOTE
A 1-Hz lissajous drift is permissible in (4) above and (6) below.
(5) Record frequency counter (A3) indication.
(6) Adjust necessary controls to obtain, on oscilloscope, a maximum intensity ellipse
within the lissajous pattern corresponding to the upper FM swing. Zero beat will occur at
approximately 10,440 Hz.
(7) Record frequency counter indication.
(8) Subtract the value recorded in (5) above from the value recorded in (7)above.
(9) Divide the difference obtained in (8) above by two. The quotient will be between
470.4 and 489.6 Hz. If not, perform b below.
(10) Add the value recorded in (5) above to the quotient obtained in (9) above. This
sum will be between 9,760.8 and 10,159.2 Hz. If not perform b below.
b. Adjustments
(1) Rotate 9960 FM DEV control (fig. 3) fully counterclockwise.
(3) Adjust 9960 FM FREQ control (fig. 3) for a 1:1 lissajous pattern.
(4) Adjust test oscillator for a frequency counter indication of 9,480 Hz.
control to obtain a maximum intensity ellipse within the lissajous pattern.
(6) Repeat a above.
16. VOR Azimuth
a. Performance Check
NOTE
On all test equipment power cords, use 2 prong to 3-prong
isolation adapters to prevent ground loops.
(1) Connect ZIFOR (A1) INPUT connector to TI AUDIO OUT jack, using cable (B8).
(2) Position TI controls as indicated in (a) through (c) below:
(a) AUDIO SELECTOR switch to VOR.
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