Radiobeacon System Map for North Atlantic (1971)

Radiobeacon System
Most radiobeacons must share a group frequency with other beacons. Therefore, radiobeacons in the same general geographical area are divided into groups of up to six beacons transmitting on a single frequency with the sequence being repeated continually. Each radiobeacon transmits for at least one-minute out of each six-minute period in sequence with the other beacons of the group regardless of weather conditions. If less than six radiobeacons are assigned to a sequence group, one or more of the beacons may transmit during two of the six one-minute periods. Various colors are used to distinguish each group on the above map.
The SEQUENCE within a group is indicated by a Roman numeral; however, an asterisk character if the station transmits twice during the six one-minute. If neither a Roman numeral or an asterisk is shown, then the beacon transmits continuously and is marked as (always black).
SERVICE RANGE is shown in miles.
The FREQUENCY is in kilohertz.
CHARACTERISTIC IDENTIFICATION consists of a combination of dots and dashes. The characteristic signal of all beacons is superimposed on a continuous carrier when they are transmitting. The last ten seconds of the minute are devoted to a long dash for maximum bearing accuracy using manual operation.
At the stations marked the radiobeacon and fog signal are synchronized for DISTANCE FINDING.
Marker radiobeacons indicated by are of low power for local use only. They operate continuously on the frequency, transmitting a series of ½-second dashes for 13½ seconds, silent 1½ seconds.

Sequenced Radiobeacons

286 I Ambrose Lighthouse No
T ( etc.)
100 40 27 32 73 49 52
286 II Fire Island Lighthouse No
RT ()
100 40 37 48 73 13 09
286 III Barnegat Lighted Horn Buoy B Buoy No
O ()
15 39 45 48 73 46 00
286 IV Stratford Shoal Lighthouse No
P ()
20 41 03 36 73 06 06
286 V Block Island Southeast Lighthouse No
F ()
70 41 09 09 71 33 07
286 VI Execution Rocks Lighthouse Yes
K ()
20 40 52 41 73 44 18
298 I Brandywine Shoals Lighthouse No
8 ()
20 38 59 11 75 06 49
298 II Five Fathom Bank Lightship No
UT ()
70 38 47 18 74 34 36
298 III Cape Henlopen Radiobeacon No
IMI ()
70 38 47 39 75 05 26
298 IV Cape Henry Lighthouse No
K ()
150 36 55 35 76 00 27
298 V Delaware Lightship No
RK ()
15 38 27 15 74 35 04
302 I Highland Lighthouse No
Q ()
150 42 02 24 70 03 40
302 II Nantucket Shoals Lightship Yes
OT ()
100 40 30 00 69 28 00
302 III Point Judith Lighthouse No
D ()
30 41 21 39 71 28 55
302 IV Chatham Lighthouse No
NO ()
50 41 40 17 69 57 02
302 V Buzzards Bay Entrance Lighthouse No
L ()
75 41 23 47 71 02 02
302 VI Boston Lightship Yes
Z ()
60 42 20 24 70 45 30
304 IV Smith Point Lighthouse No
X ()
20 37 52 47 76 11 03
304 V Wolf Trap Lighthouse No
Z ()
20 37 23 24 76 11 24
304 VI Cove Point Lighthouse No
W ()
20 38 23 10 76 22 55
306 II Little Gull Island Lighthouse Yes
J ()
20 41 12 22 72 06 29
306 III Faulkner's Island Lighthouse No
L ()
20 41 12 42 72 39 15
306 VI Montauk Point Lighthouse Yes
Y ()
20 41 04 15 71 51 27
308 II Partridge Island (Can.) Lighthouse No
U ()
50 45 14 13 66 03 17
308 III Southwest Head (Can.) Lighthouse No
N ()
50 44 36 03 66 54 20
308 IV West Quoddy Lighthouse Yes
Y ()
20 44 48 54 66 57 04
308 VI Seal Island (Can.) Lighthouse No
H ()
40 43 23 28 66 00 53
314 I Mount Desert Lighthouse Yes
B ()
20 43 58 07 68 07 44
314 II Matinicus Rock Lighthouse Yes
P ()
20 43 47 01 68 51 19
314 III Manana Island Fog Signal Yes
OE ()
100 43 45 48 69 19 38
314 IV Halfway Rock Lighthouse Yes
O ()
20 43 39 21 70 02 15
314 V Eastern Point Lighthouse No
RT ()
20 42 34 50 70 39 54
314 VI Portland Lightship Yes
K ()
50 43 31 37 70 05 31
324 II Butler Flats Lighthouse No
R ()
20 41 36 13 70 53 42
324 III Nobska Point Lighthouse No
G ()
20 41 30 58 70 39 20
324 IV Cleveland Ledge Lighthouse Yes
C ()
20 41 37 51 70 41 42
324 V Cape Cod Canal Breakwater Lighthouse No
U ()
20 41 46 28 70 29 50

Continuous Radiobeacons

290 Chesapeake Lighthouse
P ()
70 36 54 15 75 42 47

Marker Radiobeacons

292 Brenton Reef Lighthouse 41 25 35 71 23 22
294 Ocean City Inlet Lighthouse 38 19 30 75 05 18
294 Sandy Hook Channel Approach Lighted Horn Buoy 2A Buoy 40 26 31 73 55 01
302 Manasquan Inlet Radiobeacon 40 06 02 74 01 58
308 Indian River Inlet Radiobeacon 38 36 34 75 03 47
311 Shinnecock Lighthouse 40 50 32 72 28 44
316 Absecon Inlet Radiobeacon 39 21 57 74 24 37
317 Jones Inlet Radiobeacon 40 34 50 73 34 24
320 Cuckolds Lighthouse 43 46 46 69 39 02
320 Saybrook Breakwater Lighthouse 41 15 47 72 20 36
322 Barnegat Inlet Radiobeacon 39 45 28 74 06 21
324 Cape May Radiobeacon 38 56 38 74 52 20
324 Wachapreague Inlet Radiobeacon 37 34 24 75 37 03
326 Rockaway Lighthouse 40 33 07 73 56 22
Each marker radiobeacon transmits a series of ½-second dashes for 13½ seconds, silent 1½ seconds.