TB 9-4931-539-35
FREQUENCY ADJUST control setting is currently set at 265.2. This setting can be
broken down as follows:
10-8
10-9
10-10
10-11
2
6
5
.2
Because there was a decrease in the MICROSECONDS counter reading in our example,
we will add the FFE result of 2.36 x 10-9 to the current FINE FREQUENCY ADJUST
control setting. This will adjust for the phase deviation between the VLF carrier
transmission and the local oscillator. The new control setting will be:
10-8
10-9
10-10
10-11
+2
6
5
.2
2
3
.6
2
8
8
.8
If there had been an increase in the MICROSECONDS counter reading, it would have
been necessary to subtract our FFE result from the current FINE FREQUENCY
ADJUST control setting. The new control setting would be:
10-8
10-9
10-10
10-11
-2
6
5
.2
2
3
.6
2
4
1
.6
FREQUENCY CALIBRATION SYSTEM STANDARD OPERATING PROCEDURES
will be referenced to the DOD standards for time and time interval, maintained by the
USNO, or to acceptable international standards for overseas areas defined in table 1 or 2
above.
frequency to the maximum extent practicable.
10. Traceability
a. By DOD directive 5160.51, 14 June 1985, all frequency measurements must be
traceable to standards maintained by the USNO. Traceability of all U.S. Army
calibration frequency standards is maintained by utilizing standard frequency
transmissions.
b. The APSL will maintain traceability to the USNO by means of VLF radio signals
or GPS. Each TSA shall be directly traceable to the USNO through its VLF capability.
DOD VLF signals, DOD Omega signals or GPS will be used for frequency calibration.
VLF stations can be received worldwide, but the convenience of their use will vary with
