VOACAP Quick Guide

HF Propagation Prediction and Ionospheric Communications Analysis
by Jari Perkiömäki, OH6BG/OG6G

This is a 'work-in-progress' guide to using VOACAP (Voice of America Coverage Analysis Program) - free professional HF propagation prediction software from NTIA/ITS, originally developed for Voice of America (VOA). This guide should get you well started with VOACAP. A more comprehensive discussion about the finer details of using the software can be found in George Lane's book Signal-to-Noise Predictions Using VOACAP. A User's Guide. The book is now available on CD-ROM.

There is now also "The Official VOACAP Blog" - well, it's not too official.


VOACAP Online Prediction Services

Point-to-Point Predictions

11M Point-to-Point Predictions

  Coverage Area Maps

11M Coverage Area Maps

VOACAP Propagation Planner
Visual tool for HF contesters and DXers
  VOACAP DX charts
Predictions for upcoming DXpeditions

Nordic Real-Time HF Propagation Monitoring

The 24/7 real-time HF propagation monitoring cluster has been established to cover the entire HF spectrum from 1.8 MHz to 28 MHz, based on Skimmer and Skimmer Server.

What's New?

1. Downloading VOACAP

2. VOACAP - Backgrounds & Running the Prediction


The calculation engine, VOACAPW

Graphs & Colours

3. VOACAP - Understanding the Prediction



Signal Power & Noise Power

Antennas & Radiation Angles


4. VOACAP - Case Studies

5. VOACAP-related Papers

6. NTIA/ITS HF software HELP Topics

7. HamCAP User's Guide

8. Articles of interest





9. Tools & downloadable files for use with VOACAP

Find coordinates and Maidenhead grid locators just by pointing and clicking



Coordinate files

Save the coordinate files (*.GEO) at C:\ITSHFBC\GEOCITY\

Antenna and configuration files

Special Thanks
I wish to thank Mr George Lane for his friendship, invaluable comments and guidance - and his patience in this project. A special thank-you to Greg Hand who still maintains the code.

Disclaimer: Any software or service on this website is provided "as is". Use at your own risk.

© 2003-2015 Jari Perkiömäki OH6BG/OG6G. Last update: 24 July 2015.