When shuttle astronaut Owen Garriott first convinced NASA to include an amateur radio set aboard a 1983 shuttle mission, he never imagined it would one day become a permanent fixture on the International Space Station.

Garriott's mission, however, which featured highly publicized contacts with notables such as Barry Goldwater, quickly dissipated any lingering doubts.

Considering its place of honor in the upper atmosphere, much of the ham equipment used for these contacts is embarrassingly simple. In fact, the hand-held Motorola transceiver long used for shuttle flights is -- after $3,000 worth of testing -- almost indistinguishable from a model commercially available for a few hundred dollars.

Then again ham has always been a democratic, even fraternal, hobby. Hams use one another's antennas as repeaters to help send their messages leap-frogging around the globe. Hams randomly contact their radio brothers in every country in the world for the sole pleasure of saying hello and receiving a post card commemorating the contact.

Apart from equipment and electrical costs, use of designated amateur frequencies is entirely free, and there's no age limit for taking Federal Communications Commission licensing test; Barry Goldwater was a "ham," and so is Jonathan Fleischer, the 15-year-old president of his children's amateur radio club in Oxnard, California.

Like Barry Goldwater, Jonathan Fleischer got a chance to use a ham radio to say "hello" to shuttle astronauts. Jonathan's contact in 1997, in which nine other students from three organizations participated, was one of nearly 500 contacts organized by the Shuttle Amateur Radio Experiment with schools from California to Australia.

Given the array of the children's ages and interests, their questions have dealt with every facet of the human experience and curiosity, from personal hygiene to black holes and singularity ­- something about which a high school student from India once asked.

Apart from the scheduled contacts, astronauts occasionally scan the airwaves to make random contacts with fellow hams. Rosalie White of the American Radio Relay League said she once received a letter from a farmer in the Midwest who picked up the shuttle on his hand-held transceiver while plowing a field on his tractor.

"He didn't have a pen and paper on him," says White, "But he was so excited, he used a screw driver to etch the date and time of the contact on the side of his tractor."

The biggest boon with ham, however, has undoubtedly come to the astronauts themselves. At once cramped and isolated, astronauts have always had to cope with an extraordinary level of psychological stress, which is often underscored by the inability to phone home. Designating frequencies ahead of time, however, astronauts aboard the ISS will be able to use ham radio to contact family and friends at their leisure without taking up valuable time on official communications equipment -- and without having the entire mission control room listening in.

In addition to the hand-held transceiver, which looks much like a cell phone, the ham gear includes a packet module. A kind of ham modem, the packet converts radio waves into digital information and allows astronauts to exchange non-official e-mail with friends and family. One year after the initial deployment of amateur radio on ISS, NASA also plans to add ham TV.

Since ISS will function on a continual basis, chances for contacts will multiply exponentially. School contacts may happen as often as once a week, and random contacts could become daily events -- though with television on board that's hard to predict.