Make your beacon predictions using VOACAP
The NCDXF (Northern California DX Foundation), in cooperation with the IARU, has constructed and operates a worldwide network of high-frequency radio beacons on 14.100, 18.110, 21.150, 24.930, and 28.200 MHz. These beacons help both amateur and commercial high-frequency radio users assess the current condition of the ionosphere.
These automatic beacon stations transmit every three minutes on the given frequency, 24 hours a day. A transmission consists of the callsign sent in Morse code at 22 words per minute followed by four one-second dashes. The callsign and the first dash are sent at 100 watts. The remaining dashes are sent at 10 watts, 1 watt and 0.1 watts.
The current NCDXF beacon list is as follows:DX Entity Call Location Lat Lon 1 United Nations 4U1UN New York City 40 45 N 73 58 W 2 Canada VE8AT Eureka, Nunavut 79 59 N 85 57 W 3 United States W6WX Mt. Umunhum 37 09 N 121 54 W 4 Hawaii KH6WO Laie 21 38 N 157 55 W 5 New Zealand ZL6B Masterton 41 03 S 175 36 E 6 Australia VK6RBP Rolystone 32 06 S 116 03 E 7 Japan JA2IGY Mt. Asama 34 27 N 136 47 E 8 Russia RR9O Novosibirsk 54 59 N 82 54 E 9 Hong Kong VR2B Hong Kong 22 16 N 114 09 E 10 Sri Lanka 4S7B Colombo 6 54 N 79 52 E 11 South Africa ZS6DN Pretoria 25 54 S 28 16 E 12 Kenya 5Z4B Kiambu 1 01 S 37 03 E 13 Israel 4X6TU Tel Aviv 32 03 N 34 46 E 14 Finland OH2B Karkkila 60 32 N 24 06 E 15 Madeira CS3B Santo da Serra 32 43 N 16 48 W 16 Argentina LU4AA Buenos Aires 34 37 S 58 21 W 17 Peru OA4B Lima 12 04 S 76 57 W 18 Venezuela YV5B Caracas 10 25 N 66 51 W
Each station consists of a 100W transceiver and a vertical antenna.
Setting VOACAP input values
Just follow the nine easy steps below to set up your VOACAP correctly (we suppose you have made the default VOACAP installation at C:\itshfbc):
- Download ncdxf.zip (containing all user input data preset).
- Unzip ncdxf.zip (unzipped: ncdxf.voa) to the C:\itshfbc\saved\default\ directory.
- Create a directory called "user" under the C:\itshfbc\antennas directory.
- Unzip the following files to the C:\itshfbc\antennas\user directory: rxgp.zip (unzipped: rxgp.ant) and txgp.zip (unzipped: txgp.ant). These antenna files contain the typical pattern for a vertical antenna and will be used in the calculations. The files are courtesy of Fabio Bonucci, IK0IXI.
- Launch VOACAP.
- Open ncdxf.voa from the File menu (File > Open).
- Set the appropriate month and SSN (Smoothed Sunspot Number) to "Groups". The current SSN numbers can be downloaded from National Geophysical Data Center (Predicted Monthly Sunspot Numbers).
- Set the "Transmitter" location by choosing the location from a list that comes with the VOACAP package (ncdxf.geo), or by entering the transmitter location and coordinates manually.
- Set the "Receiver" location, e.g. the coordinates of your location.
Running the predictions
- Run the graphical prediction by choosing Graph from the Run menu (Run > Graph).
- When the calculations are done, you will be prompted to choose the output parameter you are interested in. Choose REL (Time availability, % time SNR exceeds required SNR).
The different colours will indicate the reliability (%) to achieve the required SNR for communication. The best reliability is shown in white and the worst in dark gray. Look at the colour legend for values.
Now when you are all set, try running the circuit analyses from various NCDXF beacon locations to your receive location, and you will get a glimpse of best times for openings to all corners of the world.