The advantage of these SWC HF products is that alternate HF frequencies can easily be found for emergency uses, even during periods of very active space weather.

 

The following information is provided:

  • recent, current, and forecast 24-hour 7.23 MHz and 3.92 MHz frequencies' availability; this network is running on 14.325 MHz where there is a "net control" and then numerous stations check in from around the country; there is no central transmission location
  • current and forecast Near Vertical Incidence Skywave (NVIS) radio-wave propagation conditions most useful where line-of-sight propagation is ineffective; the NVIS frequency range is between 1.8 and 15 MHz and is used when the communication distance is more than 50 miles (80 km) and less than 130 miles (200 km)
  • currently available global radio propagation frequencies at 3.9, 7.3, and 14.3 MHz useful for those outside the U.S. trying to reach the East Coast
  • a link to the D-Region HF Absorption and Current Solar Flare Conditions, useful for understanding whether or not a solar flare may disrupt radio communications

 

Currently Global NVIS