Tuesday, November 2, 2010
Tuesday, September 28, 2010
Before there was either commercial or government radio, there was amateur radio. Guglielmo Marconi is often quoted as saying that he considered himself to be an amateur.
At the root of the word “amateur” is the Latin verb “to love.” Radio amateurs love radio. It is an avocation pursued without pecuniary interest, although their enthusiasm often leads to employment in the field of technology or communications. To an amateur, radio is not simply a substitute for wires; it is a natural phenomenon with infinite dimensions to be explored. That was true a century ago and is still true today.
The earliest radio amateurs were students and amateur scientists. This tradition of scientific investigation and experimentation has continued to the present day. Also, radio amateurs now provide communications in the wake of natural disasters. In addition, they provide other noncommercial public-service communications and engage in activities that offer technical education, develop operating skills, and enhance international good will.
Today there are almost three million licensed radio amateurs on all continents and in nearly all countries of the world. To obtain a license, one must demonstrate technical and operational qualifications by passing a written examination administered by or on behalf of one's telecommunications administration. Most licensed amateurs are adults of all ages, both male and female, but many are students. The country with the most amateurs is Japan, with approximately 1.3 million stations currently licensed. Second is the United States with approximately 680,000. The European country with the largest number of radio amateurs is Germany, with 84,000 licensees.
The typical radio amateur became interested in electronic technology as a student. For many, amateur radio provided an opportunity to develop practical skills that influenced their career.
For example, in the mid-1950s, high school student Joseph H. Taylor, Jr. of New Jersey, USA, conducted experiments in very high frequency ionospheric propagation. In 1958 at age 17 he wrote a paper describing the results of his research that was published in the leading amateur radio periodical. He went on to become a professor of physics and in 1974, while conducting radioastronomy research, discovered ultra-dense stars called binary pulsars. For this achievement, in 1993 he was awarded the Nobel Prize in Physics. Tens of thousands of radio amateurs have made similar, if less dramatic, contributions in a wide range of scientific and technical fields. (Today, Dr. Taylor is an active radio amateur with the call sign K1JT.)
Amateur radio stations are used for two-way communication. The typical station is installed in a residence or automobile. The basic unit of equipment is a transceiver that can transmit and receive one or more modes of emission on a range of frequencies in one or more radio frequency bands. Voice emissions are the most popular, although Morse code telegraphy remains in wide use for long-distance international communication because it is effective at low power levels and with simple antennas and because it helps to overcome language barriers. Amateurs also use a wide array of digital data and image modes.
While administrations typically permit amateur stations to operate at power levels of from 400 to 2000 watts, the typical amateur station operates at 100 watts or less. Building and operating equipment that operates at very low power levels, five watts or less, is a popular and challenging activity. Antennas range from short whips for mobile and portable operation to Yagis and other high-gain, highly directive arrays, the most common being simple verticals and wire dipoles.
Amateur Service Spectrum Requirements at 7 MHz
An information paper by the
International Amateur Radio Union
International Amateur Radio Union