TB 9-6625-862-35
8. Frequency and Stability
a. Performance Check
(1) Connect TI OUTPUT terminals to multimeter and frequency counter using step
attenuator.
(2) Set step attenuator to 40 dB.
(3) Set frequency counter impedance to 1 mΩ.
(4) Adjust AMPLITUDE (OUTPUT) control for a 50 V indication on multimeter.
If frequency counter does not indicate between 196 and 204 Hz, perform b below.
(5) Vary autotransformer output between 105 and 125 V ac. If frequency indication
does not remain between 196 and 204 Hz, perform b below.
(6) Adjust autotransformer output to 115 V ac.
(7) Set FREQUENCY dial to settings listed in table 3. If frequency counter
indications are not within limits specified, perform b (1) through (8) below.
Frequency counter indications (Hz)
FREQUENCY dial settings
Min
Max
25
245
255
40
392
408
70
686
714
100
980
1020
160
1568
1632
200
1960
2040
(8) Set FREQUENCY RANGE switch and FREQUENCY dial to settings listed in
through (12) below.
Test instrument
Frequency counter indications (Hz)
FREQUENCY RANGE
FREQUENCY dial
Min
Max
switch settings
settings
X100
20
1960
2040
X100
30
2940
3060
X100
50
4900
5100
X100
100
9800
10,200
X100
200
19,600
20,400
X1
200
196
204
X1
100
98
102
X1
50
49
51
X1
20
19.6
20.4
