TB 9-6625-2296-24
(15) Set signal generator AM off and repeat technique of (7) through (14) above for
remaining signal generator and TI settings in table 22.
Table 22. Amplitude Modulation Accuracy.
Measuring 1
Signal
Test instrument indications
generator Mod
LP
MOD
Min
Max
receiver
rate
filter
range
(%)
(%)
indications
1
kHz
30%
3 kHz
Autorange
-3
+3
1
kHz
40%
3 kHz
Autorange
-3
+3
1
kHz
50%
3 kHz
Autorange
-6
+6
1
kHz
60%
3 kHz
Autorange
-6
+6
1
kHz
70%
3 kHz
Autorange
-6
+6
1
kHz
80%
3 kHz
Autorange
-6
+6
1
kHz
90%
3 kHz
Autorange
-6
+6
100
Hz
30%
3 kHz
40%
-3
+3
100
Hz
90%
3 kHz
100%
-6
+6
10
kHz
90%
15 kHz
100%
-6
+6
10
kHz
30%
15 kHz
40%
-3
+3
Set the measuring receiver filters as needed.
1
b. Adjustments
NOTE
Pressing More (F6) will scroll various options on the bottom of
the display. The options will change the functions assigned to
the F1 through F6 function keys. This may be necessary to
obtain the Freq (F1) and Atten (F4) options required in the
following tests.
(1) Press Mod (F2) (Modulation Mode), DATA SCROLL arrow keys to select AM2,
and DATA ENTRY ENTER key (to select AM2).
(2) Press the FIELD SELECT arrow keys to highlight MOD (Meter) function, and
press DATA ENTRY ENTER key (Modulation Meter).
(3) Press Range (F1) (Modulation Range) and press DATA SCROLL arrow keys to
select 100% (MOD range), press DATA ENTRY ENTER key (to select 100% AM range),
and press Ret (F6) (Return).
(4) Position signal generator controls for 80% AM, and a modulation rate of
1000 Hz. Adjust signal generator amplitude modulation until measuring receiver indicates
80% AM.
(5) Press MODE MTRS (Meters Menu), AUX (F6) (Auxiliary Functions Menu), and
DATA ENTRY 1 (Calibrations) keys. Press FIELD SELECT arrow keys to highlight 4.
Modulation Meter and press DATA ENTRY ENTER key (to select modulation meter
(6) Press DATA ENTRY ENTER key (to activate correction factor mode). Press
DATA ENTRY keys to enter value displayed on measuring receiver into TI data field, and
press DATA ENTRY ENTER key (to set new correction factor).
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