Microwave bands for Amateur Radio
Microwave frequencies are useful for more than cooking food. Most people are aware that space missions communicate using the microwave frequencies and we have seen the pictures of huge dishes used by space tracking stations such as those at Tidbinbilla, ACT for communicating with satellites and manned space missions.
Radio amateurs also successfully use these frequencies for interstate and earth-moon-earth amateur radio communications. The microwave bands, also known as the gigahertz bands, hold a special appeal to many experimentally-minded amateurs, and there is still much scope for experimentation. While commercially-available equipment for these bands is not common, a range of easily-built kits has recently come available that allow operation on these bands. Once again, the use of very high gain dish antennas means that only a small amount of power is needed to establish communication. As with the VHF/UHF bands, tropospheric ducting can allow thousands of kilometres to be spanned over large expanses water, such as the Great Australian Bight. Reflection of signals by rain showers is also a frequently used propagation mode on 10 GHz and above. This is however, limited to countries where there is rain. (Australia seems to be in a permanent drought).
There are several good Australian websites dealing with amateur microwaves, including those maintained by Robbie VK3EK, David VK5KK and Alan VK3XPD.
Other useful references are:
- Peter Day G3PHO has an excellent website illustrating what can be done on microwave bands.
- Paul Wade W1GHZ publishes a multi chapter text book on microwave antenna techniques for radio amateurs. Bookmark it!
Microwave equipment is obtainable either in kit form, or as fully assembled equipment, from:
Also parts, cables, connectors and test gear are available in Australia from Alan Devlin VK3XPD. If you are looking for connectors, cables, attenuators, dishes, horns, waveguide, amplifiers, GPS-controlled or Oven Controlled oscillators, it's also worth checking on what's being sold on Ebay, in Australia, in the US and the UK.
Next: Communicating via Amateur Satellites
