Table 1. DOD VLF Radio Stations

TB 9-4931-539-35

Station And

Call

Frequency

Type

Nominal Radiated

Location

Letters

(kHz)

Operation

Power (kW)

Maintenance Weekly Schedule

NRS(T)

NAA

24.0

MSK

1000

Mon. 1400 to 2359 UT

Cutler, ME

(universal time) (If holiday on

USA

Mon., maintenance will be

44° 38' 50" N

performed on preceding Fri.)

67° 15' 54" W

1200 to 2000 UT 2d and 4th

NCS Japan

NDT

17.4

MSK

200

1st Thurs. And Fri. Of month

Yosami, Japan

2300 to 0900 UT

34° 58' 15" N

All others Thurs. And Fri. 2300

137° 01' 18" E

to 0700 UT

NRS(T)

NLK

24.8

MSK

234

Thurs. 1600 to 2400 UT (During

Jim Creek, WA

daylight savings time)

USA

1500 to 2300 UT each Thurs.

48° 12' 15" N

Scheduled off 2 Nov 1500 to 8

21° 55' 00" W

Nov 2359 UT

NAVCAMS

NPM

23.4

MSK

600

1800 to 0400 UT last Wed. And

EASTPAC

Thurs. Of month

Laualualei, HI

1800 to 0200 UT all other Wed.

21° 25' 30" N

And Thurs.

158° 09' 20" W

NRTF

NSS

21.4

MSK

1000

1200 to 2000 UT

Annapolis, MD

Testing 2000 to 2200 UT Tues.,

USA

Operator training 1800 to 2000

38° 59' 30" N

UT 2d and 4th Thurs.

NCS H.E. HOLT

NWC

22.3

MSK

1000

Mon. 000 to 0800 UT

NWC Australia

21° 49' 01" S

114° 09' 50" E

NIST

WWVB

60.0

VLF

No Scheduled Maintenance

BOULDER, CO

USA

Aquada P.R. NAU

NAU

28.5

MSK

100

1200 to 2000 Wed.

Rugby, England

GBR

16.0

FSK

750

1000 to 1400 UT Tues.

1May

be used if no DOD stations are available.

6. Frequency Measurement. Use of the 599J/K receiver for frequency calibration of a

local standard is simple and straightforward. Any relative frequency error between the

local frequency standard and the received VLF carrier signal is observable as a phase

drift on the MICROSECONDS digital counter and on the strip chart recorder. The rate

of this phase drift can be directly interpreted as a fractional frequency error (FFE) in

the local standard. The FFE for observed phase changes over various elapsed time

intervals can be obtained using the conversion factors listed below: