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Courtesy of the U.S. Coast Guard

Radio fax, also known as radio facsimile or weather fax, is a meansof broadcasting graphic weather maps and other graphic images via HF orshortwave radio. Maps are received using a dedicated radio fax receiver.Pictures can also be received using a single sideband shortwave receiverconnected to an external facsimile recorder or PC equipped with a radiofax interface and application software.

The National Weather Service (NWS) radio fax program prepares high seasweather maps for broadcast via four U.S. Coast Guard (Boston, New Orleans,Pt. Reyes, and Kodiak) and one DOD transmitter site (Honolulu). These broadcastsare prepared by the Marine Prediction Center, Tropical Prediction Center,Honolulu Forecast Office. and Anchorage Forecast Office. Limited satelliteimagery, sea surface temperature maps and text forecasts are also available.The International Ice Patrol also broadcasts radio fax charts from Bostonsharing the same transmitters.

The U.S. Navy terminated all regularly scheduled radio fax transmissionswith the exception of the Mediterranean beginning January 1, 1998. Thesystem is operated in a back-up mode for on-demand service by fleet unitsupon request. Previous plans to permanantly terminate the Navy radio faxprogram by January 1, 1999 were under review and no additional informationis currently available on the status of that program. These transmissionsare to meet the requirements of the U.S. military and have no direct connectionto the National Weather Service's radio fax program.

Table 1 below is an abbreviated version of the NWS radio fax broadcastschedules. All radio fax broadcasts of National Weather Service productsemploy a radio fax signal of 120 lines-per-minute (LPM) and an Index-ofCooperation (IOC) of 576. These values must be entered into the users equipmentor software program in order for the radio fax image to be displayed properly.

Radio Fax BroadcastBoston, Massachusetts (NMF): 6340.5, 9110 and 12750 kHz Start Broadcast 0230Z   0800Z   1430Z   2005ZBroadcast Schedule      0243Z   1903Z   Ice (Seasonal, ~Feb- Sep)       1600Z1  1810Z11 International Ice Patrol, call letters NIK. New Orleans, Louisiana (NMG): 4317.9, 8503.9 and 12789.9 kHz Start Broadcast 0000Z   0600Z   1200Z   1800ZBroadcast Schedule      0630Z   1830ZKodiak, Alaska (NOJ): 2054, 4298 and 8459 kHzStart Broadcast 0400Z   1000Z   1800Z   2200ZBroadcast Schedule (Mon, Fri)   1838ZPoint Reyes, California (NMC): 4346 (except 2300Z), 8682, 12730, 17151.2 and 22527(2300Z) kHz Start Broadcast 0245Z   0815Z   1100Z   1415Z   2015Z   2300ZBroadcast Schedule      1104Z   2324ZHonolulu, Hawaii (KVM70): 9982.5, 11090, 16135 and 23331.5 kHz Start Broadcast 0533Z   1150Z   1733Z   2350ZBroadcast Schedule      0533Z   1150Z   1733Z   2350Z(Note: National Weather Service station, not U.S. Coast Guard)

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