TB 9-4920-360-35
Test instrument
Frequency counter indications (Hz)
FUNCTION SWITCH
FREQ adjustments
settings (%RPM)
switch settings
Min
Max
2.079 ms1
5
+5
2.087 ms
1
5
-4
20.791 ms
20.875 ms
1
5
-5
20.791 ms
20.875 ms
15
0
718.56
721.44
70
0
3353.28
3366.72
90
0
4311.36
4328.64
110
0
5269.44
5290.56
110
-5
5029.92
5050.08
110
-4
5077.82
5098.18
110
-3
5125.73
5146.27
110
-2
5173.63
5194.37
110
-1
5221.54
5242.46
110
+1
5317.34
5338.66
110
+2
5365.25
5386.75
110
+3
5413.15
5434.85
110
+4
5461.06
5482.94
110
+5
5508.96
5531.04
1Set
frequency counter for period measurement. When the FUNCTION SWITCH is at 5 percent and the variable
frequency adjustment is at -5, the frequency output is 1 percent rpm (not 0 percent rpm), equivalent to 48 Hz or 20,833
ms.
b. Adjustments
(1) Connect frequency counter to TP1 (fig. 1).
(2) Adjust R10 (fig. 1) for indication of 1 MHz on frequency counter.
10. Final Procedure
a. Deenergize and disconnect all equipment.
b. Annotate and affix DA label/form in accordance with TB 750-25.
