TB 9-6625-086-35
Table 5. Range and tracking Performance Check (Without Power Meter Calibrator) - Continued
Test
Test
Dc Voltmeter Indications (vdc) (Readings
Adjustments for Model
Instrument
Instrument
for Model 431B are in Parenthesis)
431C (fig. 3)
Switch
Indication
200-Ohm Mount
100-Ohm Mount
200-Ohm
100-Ohm
Settings
Min
Max
Min
Max
Mount
Mount
3
3
7.67
7.83
10.84
11.06
R9
R6
(7.52)
(7.98)
(10.6)
(11.3)
10
10
14.00
14.28
19.80
20.20
R8
R7
(13.7)
(14.6)
(19.4)
(20.6)
10
8
12.52
12.78
17.71
18.07
(12.3)
(13.0)
(17.4)
(18.4)
10
6
10.84
11.06
15.34
15.64
(10.6)
(11.3)
(15.0)
(16.0)
10
4
8.85
9.03
12.52
12.78
(8.67)
(9.21)
(12.3)
(13.0)
10
2
6.26
6.38
8.85
9.03
(6.13)
(6.51)
(8.67)
(9.21)
NOTE
Each time the TI RANGE switch is changed, turn the dc power
supply off and zero the TI meter.
(7) Repeat the technique in (5) and (6) above for the remaining positions of the TI
RANGE switch. If both a 200-ohm and 100-ohm thermistor mount is available, perform (1)
through (6) above for both mounts.
adjustment can be made on model 431B.
12. Oscillator Frequency
NOTE
Do not perform the oscillator frequency check if all parameters
in paragraphs 8 through 11 above are within tolerance.
a. Performance Check
(1) On model 431C, connect frequency counter (A4) to the positive end of C18 (fig. 1)
and ground, using cable (B4). On model 431B, connect the counter to the positive end of
C125 (fig. 2) and ground.
(2) Connect 200-ohm thermistor mount (A8) to the TI and terminate the mount
with termination (B6).
(3) Set the TI MOUNT RES switch to 200Ω.
(4) If the frequency counter does not indicate between 9,990 and 10,010 Hz for
model 431C, perform b(1) below. For model 431B, if the frequency counter does not
indicate between 10,025 and 10,275 Hz, perform b(2) below.
11
