What is Amateur Radio?

What is Amateur Radio?

If you were to ask a dozen different amateurs what ham radio meant to them chances are you would get 12 different answers. Radio amateurs have discovered a richly rewarding high-tech hobby that has many different appeals to different people. Whether it is the ability to talk to local friends over the radio waves using a hand-held transceiver (HT), communicating digitally with packet radio to exchange personal messages or vital information in an emergency, talking to other hams anywhere in the world, or engaging in contests with other Radio Amateurs over the airwaves there is something for everyone.

Amateurs or Hams?

Amateurs are often affectionately called hams or ham radio operators and frequently the public is more familiar with this term than with the legal term Radio Amateur. The source of the name ham is not known but it has been around almost from the beginning of amateur radio in the early 1900s. The name amateur has nothing to do with skill or knowledge but rather implies that ham radio cannot be used for commercial or revenue generating purposes. It is truly a hobby but often one that makes a difference especially in emergency or disaster situations.

Modes of Communication

Amateur radio operators generally use radio transmitters and receivers to communicate with each other. As you will discover in these pages there are many forms of communication although voice (also known as phone) is still the most widely used. Some of the other forms of transmission are Radioteletype (Rtty), Morse code (CW), television, and digital modes such as Packet, Pactor and PSK-31. A recent survey shows that phone is the most widely used with CW standing second.

Getting Licensed

To become a radio amateur, you will need to get a license. Licensing requirements are different in every country with different rules, privileges, and classes of license. Basically, different levels of license give different privileges on the ham bands. The more challenging the license requirements the more privileges that are granted and the more interesting and enjoyable ham radio becomes.

HF Packet Challenges

Amateurs have been using packet radio on the HF bands for as long as packet radio has existed. And we have been less than happy with the results for about the same length of time.

The problem is centered on the way packet radio operates. Data is packaged into individual frame, which are then sent by the transceiver using two-tone audio frequency shift keying. If even one bit is corrupted within a packet radio frame at the receiving end. the entire frame must be re-transmitted. If the signal path is marginal, several retransmissions may be required to get the information through.

At VHF and above, packet is typically sent using FM transceivers and line-of-sight links, so corruption is kept to a minimum and the data flows reasonably well. At HF, it is a whole different ballgame. Now the packet signal must compete with noise, interference, and fading. Unless the signal path between two stations is particularly stable, corrupted data can become an enormous problem. The result can be a seemingly endless round of re-transmissions, or a complete communication breakdown.