Injectable nanogel can monitor blood-sugar levels and secrete insulin when needed.
From communicating with disaster-stricken parts of the world to organizing airport pick-ups of arriving freshmen, MIT's ham radio club has been putting its skills and equipment to practical use for most of this century.
Members of W1MX, the short-wave station's call letters, talk with other radio operators around the world from their headquarters on the top floor of Walker Memorial. Outside the window runs a thin, ladder-like wire that extends to the roof of East Campus and thence to one of the club's antennas atop the Green Building. Another station with many of the same members, W1XM, broadcasts and receives VHF signals from a shack on the same tall building. Those signals are about 10 times the frequency of those sent and received by W1MX, which generally operates in the range of 3 MHz to 30 MHz.
Ham radio enthusiasts are probably best known for establishing links with people in places where normal communications have been disabled by war or natural disaster. Bosnia, for example, is one place W1MX members and others have been in contact. Because each amateur facility is independently manned and powered, "in emergencies, typically quite a few of them survive" to provide outside contact, noted Stephen Finberg, a former station manager who now works at the Draper Laboratory.
After the recent earthquake in Kobe, Japan, amateur radio was used more for internal communication with emergency personnel than with the rest of the world, since most Japanese ham operators have only a basic license that doesn't allow global communications, explained Matt Reynolds, W1MX vice president and station manager, who is a sophomore in electrical science and engineering.
To practice their emergency preparedness and engage in some good-natured competition at the same time, ham radio operators set up field stations in outdoor locations nation-wide during the last weekend in June and try to contact as many other stations as possible in a 24-hour period. In recent years, W1MX has set up shop on the steps of the Student Center during the event. At other times, radio contacts to distant points are confirmed by mailing QSL cards (QSL is a radio code for "Can you acknowledge receipt?").
Although radio signals travel in a straight line, at some frequencies, they can travel between two points on the planet's curved surface by skipping off the ionosphere one or more times and returning to Earth somewhere over the horizon. The frequency at which this occurs is variable and depends on the solar ion flux, the condition of the upper atmosphere and the time of day. "This is what makes the HF band so interesting. You never know what you're going to get," said Tim Shepard, a graduate student in electrical engineering and former club officer.
Chatting with fellow operators in faraway places is only one activity of the club, however. Members also act as dispatchers for vans of students who pick up freshmen arriving at Logan Airport during R/O each fall, and they also provide radio checkpoints during the annual Community Service Fund road race. In addition, they administer many of the region's FCC exams for ham licenses, and they run a monthly Swap Fest during the summer months where people come from all over New England to buy and sell used electronic equipment.
The history of amateur radio on campus goes back to early 1909, when both MIT and Harvard founded the first college stations in the country, although there is still friendly debate as to which edged out the other. (There is also no consensus over the origin of the word "ham;" some say it is an abbreviation of "home amateur," while a few believe it is the initials of the three founders of the hobby). MIT established the first transatlantic voice link in 1924, the year after the late President Julius A. Stratton-a former secretary of the club-graduated from MIT. "Radio back then was the cutting edge, like computers today-it was something that brought people to MIT," observed Wayne Baumgartner, a junior in physics and W1MX president.
Like Dr. Stratton, many people find their way into engineering as a result of tinkering with radio sets in their youth. As a high school student in Raleigh, NC, Mr. Reynolds drove around with a police officer after a tornado had heavily damaged parts of the city. While the police backup communications system was being readied, he filled the gap with a hand-held radio and his club's repeater (a device usually placed on a tall building that picks up, amplifies and retransmits messages to their destinations).
W1MX can also provide a practical application for classroom knowledge. "A lot of people pick up hands-on experience through ham radio," Mr. Reynolds said. Although it is a relatively old branch of electrical engineering, radio has recently become a booming field again with the recent growth of wireless communication such as cellular telephones, Mr. Finberg noted.
Though venerable, the hobby of amateur radio is always taking advantage of the latest technologies. There are currently about 23 repeaters on small satellites built by ham radio operators that have been launched into orbit aboard experimental rockets, Mr. Reynolds said. Equipment on other, even smaller satellites can receive ham radio transmissions over one spot on Earth, store them and then download them to the recipient when the satellite is over that location.
W1MX plans to assemble a new station in its current headquarters to make better use of these satellites. In addition, two digital repeaters maintained by the club offer a non-commercial Internet gateway whereby computers can communicate via radio signals. Elsewhere, some VHF clubs with access to large antennas are even developing ways to bounce signals off the moon, Mr. Baumgartner said.
For the immediate future, club members are planning the challenging task of installing a new rotatable antenna on the Walker roof, replacing the current one which is stuck pointing northeast. Acquiring, assembling and maintaining equipment probably takes up more time than actually using it, particularly when lightning strikes an antenna protruding from the tallest building in Cambridge. "Every six or seven years, they get blown to bits," Mr. Finberg said.
Anyone interested in joining W1MX or learning more about their services can call x3-3776 or e-mail
A version of this article appeared in MIT Tech Talk on March 1, 1995.