Radiobeacon System Map for North Atlantic (1952)

Radiobeacon System
FREQUENCY is given in kilocycles.
CHARACTERISTIC CODE is shown in combinations of dots and dashes.
UNITED STATES and CANADIAN radiobeacons, in general, are assigned group frequencies and definite operating minutes. The sequence within a group is indicated by a Roman numeral. Stations with the same sequence numbers transmit during the same minute.
When a Roman Numeral is shown, the characteristic code is transmitted for 60 seconds, silent 120 seconds during fog or low visibility and during two 10 minute periods out of each hour in clear weather.
If no Roman numeral is shown, the radiobeacon characteristic code is transmitted continuously.
The scheduled 10 minute periods of each hour of clear weather are not displayed on the map but is shown in the table of sequenced radiobeacons. For example, a clear weather schedule of 1-4 indicates that the characteristic code is transmitted during the first and fourth 10 minute periods of the hour. The last minute of each clear weather 10 minute period is silent. (See clock face diagram on map for definition of each clear weather period.)
If no clear weather schedule is shown, the radiobeacon characteristic code is transmitted for 60 seconds, silent 120 seconds when a Roman numeral is shown, and continuously when no Roman numeral is shown.
At the stations marked the radiobeacon and sound signal are synchronized for DISTANCE FINDING.
Radiobeacons marked are of low power for local use only. They operate continuously on the frequency and they have special characteristics as indicated for each case. The above notes relative to sequence, characteristic, and schedule do not apply to these radiobeacons.
The service range is a reliable average range as follows:
      Class A: 200 Miles
      Class B: 100 Miles
      Class C: 20 Miles
      Class D: 10 Miles

Sequenced Radiobeacons

286 I Ambrose Lightship 3-6 Yes  etc.B 40 27.1 73 49.4
286 II Barnegat Lightship 3-6 Yes B 39 45.8 73 56.0
286 III Fire Island Lighthouse 3-6 No B 40 37.8 73 13.2
288 I West Quoddy Lighthouse 1-4 Yes C 44 48.9 66 57.1
288 II Hen and Chickens Lightship 1-4 Yes C 41 27.0 71 01.1
288 II Mount Desert Lighthouse 1-4 Yes C 43 58.1 68 07.7
288 III Portland Lightship 1-4 Yes B 43 31.6 70 05.5
290 I Cross Island (Can.) Lighthouse 1 No
Three times
C 44 18.7 64 10.1
290 I Cross Rip Lightship 1-4 Yes C 41 26.9 70 17.5
290 I Smith Point Lighthouse 2 Yes C 37 52.8 76 11.0
290 II Cape Henry1 2 Lighthouse Yes A 36 55.6 76 00.4
290 III Wolf Trap Lighthouse 2 Yes C 37 23.4 76 11.4
292 I Eastern Point Lighthouse 3 No C 42 34.8 70 39.9
292 II Cape Cod Canal Breakwater Lighthouse 3 No C 41 46.5 70 29.8
292 III Nobska Point Lighthouse 3 No C 41 30.9 70 39.4
294 I Matinicus Rock Lighthouse 2-5 Yes C 43 47.0 68 51.3
294 I Point Judith Lighthouse 3 No B 41 21.7 71 28.9
294 II Little Gull Island Lighthouse 3 Yes C 41 12.4 72 06.4
294 III Partridge Island (Can.) Lighthouse 1-4 Yes
Three times
C 45 14.4 66 03.3
296 III Sambro (Can.) Lightship 1-4 No
Three times
B 44 21.8 63 25.7
298 II Stone Horse Lightship 1-4 Yes C 41 32.8 69 59.1
298 II Winter Quarter Lightship 1-4 Yes B 37 55.5 74 56.4
298 III Five Fathom Bank Lightship 1-4 Yes B 38 47.3 74 34.6
300 III Manana Island Fog Signal 1-4 Yes B 43 45.8 69 19.7
302 I Highland1 Lighthouse No A 42 02.4 70 03.7
302 II Boston Lightship 2-5 Yes B 42 20.4 70 45.5
302 III Vineyard Sound Lightship 2-5 Yes B 41 22.6 71 00.2
306 I Cove Point Lighthouse 1 Yes C 38 23.2 76 22.9
306 II Montauk Point1 Lighthouse Yes C 41 04.3 71 51.4
306 II Overfalls Lightship 1-4 Yes B 38 48.0 75 01.4
306 III Sandy Point Shoal2 Lighthouse 1 Yes C 39 01.0 76 23.1
308 I Cleveland Ledge Lighthouse 3-6 Yes B 41 37.9 70 41.7
308 I Cornfield Point Lightship 1-4 Yes C 41 12.9 72 22.2
308 I Western Head (Can.) Fog Signal 2 No
Three times
B 43 59.3 64 39.7
308 II Lurcher Shoal (Can.) Lightship 2 No
Three times
B 43 48.5 66 31.8
308 III Seal Island (Can.) Lighthouse 2-5 No
Three times
B 43 23.5 66 00.9
310 I Execution Rocks Lighthouse 3 Yes C 40 52.7 73 44.3
310 II Brenton Reef Lightship 1-4 Yes C 41 25.6 71 22.6
310 II Stratford Shoal Lighthouse 3 Yes C 41 03.6 73 06.1
312 I Chesapeake Lightship 1-4 Yes B 36 58.7 75 42.2
312 III Halfway Rock Lighthouse 3-6 Yes B 43 39.4 70 02.2
314 I Pollock Rip Lightship 2-5 Yes A 41 36.1 69 51.1
314 II Nantucket Shoals1 Lightship Yes A 40 37.0 69 38.3
314 III Block Island Southeast1 Lighthouse Yes B 41 09.2 71 33.1
 1 Characteristic code superimposed on a carrier which is on for 60 seconds and off for 120 seconds.
 2 Also Special Radio Direction Finder Calibration Station.

Continuous Radiobeacons

294 Scotland1 Lightship C 40 26.6 73 55.2
 1 Characteristic code superimposed on a carrier which remains on continuously.

Marker Radiobeacons

292 Cape May West Jetty1 Lighthouse ½ sec. dash repeated for 13½ sec., silent 1½ sec. D 38 56.0 74 52.0
296 Butler Flats1 Lighthouse ½ sec. dash repeated for 15½ sec., silent 14½ sec. D 41 36.2 70 53.7
300 Newport News Middle Ground2 Lighthouse ½ sec. dash every sec. D 36 56.7 76 23.5
312 Manasquan Inlet South Breakwater1 Lighthouse ½ sec. dash repeated for 13½ sec., silent 1½ sec. D 40 06.0 74 01.9
 1 Marker radiobeacon, operates continuously.
 2 Marker radiobeacon, operates for calibration purposes only upon request.