TB 9-6625-1947-24
8. Frequency Accuracy, Stability, and Range
a. Performance Check
(1) Connect frequency counter to TI COUNTER OUTPUT connector (rear panel),
using 50 feed-through termination.
(2) Set FREQUENCY RANGE switch to X10 and rotate FREQUENCY dial fully
cw. Frequency counter will indicate 10 Hz or less.
(3) Set FREQUENCY RANGE switch to X1M and rotate FREQUENCY dial fully
ccw. If frequency counter does not indicate 10 MHz or more, perform b below.
(4) Set FREQUENCY RANGE switch to X10 and FREQUENCY dial to 1.
If
frequency counter does not indicate between 9.70 Hz and 10.30 Hz, perform b below.
If frequency counter does not indicate within limits specified, perform b below.
Table 3. Frequency Accuracy Check
Test Instrument
Frequency counter indications
FREQUENCY
REQUENCY
RANGE
Min
Max
dial settings
switch settings
X10
5
48.5
Hz
51.5
Hz
X10
10
97
Hz
103
Hz
X100
1
98
Hz
102
Hz
X100
5
490
Hz
510
Hz
X100
10
980
Hz
1020
Hz
X1K
5
4.9
kHz
5.1
kHz
X1K
10
9.8
kHz
10.2
kHz
X10K
1
9.8
kHz
10.2
kHz
X10K
5
49.0
kHz
51.0
kHz
X10K
10
98.0
kHz
102.0
kHz
X100K
1
98.0
kHz
102.0
kHz
X100K
5
490.0
kHz
510.0
kHz
X100K
10
0.98
MHz
1.02 MHz
X1M
1
0.98
MHz
1.02 MHz
X1M
5
4.90
MHz
5.10 MHz
X1M
10
9.6
MHz
10.4
MHz
(6) Position controls as listed in (a) through (d) below:
(a) FREQUENCY RANGE switch to X1K.
(b) FREQUENCY dial to 1.
(c) OUTPUT LEVEL dBm switch to +10.
(d) Press IMPEDANCE 50 UNBAL pushbutton.
(7) Adjust AMPLITUDE control for a +10 dBm indication on TI meter.
If
frequency counter does not indicate between 980 Hz and 1020 Hz, perform b below.