When all else fails, there will always be radio.

That’s the way that amateur radio hobbyists see themselves, said longtime instructor Tom Scott.

Scott, who teaches a six-week course in Ledyard to get a radio technician license, has taught people how to operate amateur radio since the mid-1980s. He said people join his class for a variety of reasons, but the accessibility and omnipresence of radio is a big draw.

“Even if the phone lines are down, if you want to talk to Washington or the West Coast, we can do that,” he said. “And we can do it with radios that can be operated off your car battery.”

The attachment to amateur radio in the region is in part a holdover from the Navy Underwater Sound Laboratory, which operated at Fort Trumbull in New London for decades.

“In the lab, there had been radio and periscope systems, engineers, scientists: a significant number of people were amateur radio operators,” Scott said.

When the lab moved in the 1990s, most employees moved to Newport, R.I., but “some stayed here and retired,” Scott said. “And they’re dying off fast.”

Members of radio organizations in the area often turn out at local events but have an understated presence. They volunteer at triathlons in Mystic and Niantic Bay to provide “eyes and ears” to organizers, and coordinate with local relief organizations and municipal aid agencies in the event of a winter storm or disaster.

“We report any problems that happen, and (are) in contact with the police if something happens,” Scott said.

In the case of major road races, “operators are stationed along the course to report the progress of the runners and also provide help and welfare coverage,” he added.

Seven radio enthusiasts present at Scott’s class Jan. 18, who were learning the technical challenge of calculating resistance, included a mixture of people brushing up on their skills and younger folks interested in the medium.

All are preparing for a 35-question test at the end of the course, which will grant them selective access to bands in the electromagnetic spectrum – where amateur radio lives.

Weijie Wang, an education consultant from Gales Ferry, said he originally became interested in radio because of the sci-fi movie “Spectrum,” but during the first class was surprised to learn how many things were possible through radio, like communication with astronauts in space.

He plans to continue on to get his technician license.

“(Spectrum) is a science fiction movie — and it doesn’t exaggerate the power of radio,” Wang said.

n.lynch@theday.com