Section V
TM 11-6625-2781-14&P-2
ADJUSTMENT PROCEDURES (cont'd)
5-23. Tuning Range Adjustment (cont'd)
ANALYZER Control Settings (cont'd)
SCAN MODE ................................ ................................ ................................ ................................ ....................... INT
SCAN TRIGGER ................................ ................................ ................................ ................................ .............. LINE
8406A
COMB FREQUENCY -MC ................................ ................................ ................................ ............................ 100 MC
INTERPOLATION AMPLITUDE................................ ................................ ................................ ......................... OFF
OUTPUT AMPLITUDE................................ ................................ ................................ ................................ .3 o'clock
2.
Center FINE TUNE. Adjust FREQUENCY until dial pointer is centered on 100 MHz.
3.
Adjust A6A1R13 TUNING RANGE so that 100 MHz comb signal is directly over graticule line.
4.
Select the 10 MC COMB FREQUENCY on the 8406A.
5.
Tune the analyzer FREQUENCY control across the band. Go from 100 MHz down to 0 MHz stopping at 10 MHz
increments. The comb signals should be aligned with the center frequency mark on the display 5 divisions (1
MHz).
-5 ________+5 Div
6.
At 0 MHz, a slight adjustment of A7A1R3, LOW FREQ ADJ, will bring the local oscillator feedthrough signal to
the center of the display.
7.
Retune FREQUENCY to 100 MHz. If necessary, readjust A5A1R13 to center the display.
8.
Tune FREQUENCY to 90 MHz. The display should be centered 5 divisions (1 MHz).
9.
Set FREQUENCY to 50 MHz, BANDWIDTH to 300 kHz, and SCAN WIDTH PER DIVISION to 10 MHz.
10.
Turn FREQUENCY until the 50 MHz comb signal is exactly on the center graticule.
11.
Set SCAN WIDTH to 0-100 MHz.
12.
Adjust A4R7 SCAN ADJ on the A4 Scan Assembly until the 50 MHz comb signal is exactly on the center
graticule.
13.
MHz comb signal.
14.
Switch SCAN WIDTH to PER DIVISION. The 50 MHz comb should be centered t 4 divisions (+400 kHz).
-4 _________+4 Div
5-9
