VOACAP or Voice of America Coverage Analysis Program for HF Propagation Prediction

 VOACAP or Voice of America Coverage Analysis Program for HF Propagation Prediction is a free software, originally developed for Voice of America by Institute for Telecommunication Sciences, the research and engineering arm of National Telecommunications and Information Administration (NTIA). OH6BG has a web portal which provides predictions for amateur radio HF bands from 3.5 to 28 MHz. That portal has additional options of VOACAP for Marine HF band from 2 to 25 MHz and VOACAP for 11m or the Citizen band which gives from 26 to 28 MHz. There are also VOACAP DX Charts which gives HF propagation predictions for amateur radio DXpeditions, VOACAP Greyline which gives Sun related data for any given location like times for sunrise, sunset, dawn, dusk, solar midnight and Space weather charts and indices.

There is a VOACAP for Ham Radio User's Manual in pdf format available for download on the OH6BG website, which runs into 39 pages and is worth going through before using the HF propagation prediction charts. 



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