TB 9-6625-2089-24
Table 3. Internal PRF Frequency Accuracy
Test instrument
Frequency counter indications
PRF SELECT
(Hz)
control settings
(R)
RANGE
MULT
Min
Max
X1K
10.00
9000
11000
A1R3 for 10000 Hz
X100
10.00
900
1100
---
X100
1.00
90
110
A1R14 for 100 Hz
X10
1.00
9
11
---
X10
10.00
90
110
A1R19 for 100 Hz
(4) Set MEASUREMENT PRF RANGE switch to X10 and PRF SELECT MULT
control for a measurement meter indication of 1.5. Frequency counter will indicate between
13.5 and 16.5 Hz.
(5) Position controls as listed in table 4. If frequency counter does not indicate
within limits specified, perform adjustments in table 4.
Adjustments
Test instrument
Frequency counter
indications
PRF
Measurement
Measurement
(R)
(Hz)
SELECT
PRF RANGE
meter
RANGE
indications
Min
Max
X10
X10
10.0
95
105
A10R24 for 100 Hz
X100
---
1.0
90
110
---
X100
X100
10.0
950
1050
A10R20 for 1000 Hz
X1K
---
1.0
900
1100
---
X1K1
X1K
10.0
9500
10,500
A10R16 for 10,000 Hz
1If
measurement meter does not indicate full scale, perform b (2) and (3) below.
(6) Set MEASUREMENT FUNCTION SELECT switch to PRF REPLY.
Measurement meter will indicate 10.0.
b. Adjustments
(1) Adjust A1R9 (fig. 1) for a frequency counter indication of 1000 Hz (R).
(2) Connect oscilloscope to A10TP3. Adjust PRF SELECT MULT control until
(3) Adjust A10R27 (fig. 1) for a pulse width of 99.0 μs as indicated on oscilloscope (R).