Satellite Dissemination

Satellite broadcast is one method used by the NWS and others for disseminating the EMWIN data stream. Our goal is to make the data stream available nationwide, but not to provide detailed support (i.e. funding, manpower, or equipment) for state and local efforts to redistribute the data stream after downlink.

The NWS broadcasts EMWIN on NOAA's GOES East and GOES West satellites. GOES East is at 75 degrees West, elevation 45 degrees (from the latitude of Washington, DC). GOES West is at 135 degrees West. Data is uplinked to satellite from the NOAA Command and Data Acquisition (CDA) Station on Wallops Island, VA.

The GOES downlink frequency used for the 9600 baud EMWIN datastream is 1690.725 MHz, 275 KHz lower than the standard WEFAX 1691.0 MHz signal. The signal is passed through a down convertor, received as if a Radio signal at 137.225 MHz for example, and then demodulated to 9600 baud.

The EMWIN data stream is also currently uplinked to the Telstar 5 Satellite, located at 97 degrees West. The center frequency of the Telstar 5 EMWIN signal is 12,185 MHz, subcarrier frequency is 1.065 MHz.

If you need equipment, see the list of Commercial Vendors.