It’s common lore on the Vineyard that when the President visits, wireless communications immediately improve due to upgrades installed for reasons of national security.

But emergency responders who have been struggling with an array of problems with radio communications this summer have a decidedly different story to tell.

Following a mandate from the federal government, beginning two years ago police, fire and ambulance departments across the country were required to cut in half the amount of bandwidth used for emergency communications. The change also affected frequencies used by public utilities, schools and mass transit agencies. Each agency is assigned and licensed for a set of frequencies to exclusively transmit and receive radio communications; as a result there was little room left to issue new licences. By requiring the use of new, more efficient technologies, the FCC intended to open up a larger spectrum of frequencies for new departments or agencies needing to expand.

On the Vineyard every base, mobile and portable police and fire radio on the Vineyard was modified to meet the requirements. But the transition has not been smooth, and in times of emergencies, radio communications have been spotty.

A long-term plan is in place to correct the problem and Island emergency managers say there is no threat to public safety.

“We haven’t had an emergency where something that should have happened didn’t happen,” said Dukes County Sheriff Michael McCormack. “It’s become sort of a pain, people have to repeat themselves or call more than one time, or the transmissions are broken up. It’s more of an aggravation than a safety issue, although I suppose it could be, in a certain set of circumstances, a safety issue.”

Tom Bardwell of Bardwell Electronics in Vineyard Haven, the contractor that helps Island first responders deploy and maintain radio systems, said there are more than 1,000 two-way radios currently in use on the Island. To meet the new bandwidth requirement, technicians had to modify every emergency radio. Now Bardwell is in the process of ordering and installing new electronic programming cards in most of the radios. Sheriff McCormack said the work should be completed by the end of summer.

Meanwhile, issues with reduced coverage range were immediately apparent beginning early this year. At times police officers could not reach the communications center, located near the Martha’s Vineyard Airport, by radio. During an early summer house fire in a remote area of Vineyard Haven, firefighters had difficulty communicating with each other by radio. Most of the problems are with portable radios carried by first responders, usually lower power devices compared with the mobile radios installed in vehicles and at base stations.

“We’ve had a degradation in our radio signal, it’s detectable,” said Lieut. Eerik Meisner of the Tisbury police department. “There are some areas that are more prevalent than others, in terms of radio communications.”

To compensate for the reduction in range, Tisbury police began using a repeater located in Oak Bluffs. A repeater receives a weaker two-way radio signal and retransmits it at a higher power.

“It improved things, absolutely,” Lieutenant Meisner said. “Probably in Tisbury, we’ll be working toward getting our own repeater in town.”

Edgartown police chief David Rossi said technology upgrades often cause initial difficulties. But he said the current system that involves using different repeaters that may not necessarily work across towns or agencies needs improvement.

“It’s kind of ridiculous,” the chief said. “Sometimes you can call and you may not be able to hear somebody that’s just a house away.”

Still, he said the problem is unlikely to place the public or an officer in danger.

“Could it happen? Yes. It’s not good, but should there be a panic? No,” Chief Rossi said. “I don’t think it’s at that level.”

In remote Aquinnah, police chief Randhi Belain said his department has experienced few problems.

“I think because of the repeater on Peaked Hill, we’re not so affected by the narrow banding,” he said. “We’re more on cruiser radios than portables most of the time. We know whenever you can get to a mobile radio rather than a portable radio, you want to do that. That’s not to say there aren’t issues, because we know there are.”

For the future, the Martha’s Vineyard Law Enforcement Council is considering a different technology for emergency communications. Instead of using five repeater sites around the Island, new technology would provide simulcasting capability. Dispatchers at the communications center would send a radio transmission, which would use land-based phone lines to relay the signal to portable, mobile and base radios.

“That should immensely improve our ability to communicate,” Sheriff McCormack said. The upgrade will be expensive; a preliminary cost estimate came in at more than $1 million.

Also in the works is a regional channel mapping and planning exercise that would allow dispatchers to designate a specific channel for an individual event like a fire or an accident.

Mr. Rossi said Island departments are working hard to correct the problems, noting that beyond all the complex technical issues, it is critical that first responders be able to communicate with each other, and with their dispatchers.

“When I pick up the radio and use it,” he said, “I want somebody on the other end to hear me.”