“Greetings, virus people!”

The on-air patter was hardly what you would expect from a radio D.J. addressing his listeners during a pandemic last week. But Ken Freedman, the station manager and program director at Jersey City’s WFMU 91.1 and 91.9 FM — broadcasting to the greater New York City area, “Your station from the epicenter!” — sounded practically chipper.

Like the rest of the country’s noncommercial, community radio programmers, Freedman has been forced into hastily improvising a response to the growing spread of Covid-19. Staffed largely by volunteer D.J.s taking time away from paying jobs as teachers, bartenders and everything in between, these scrappy local stations have had little in the way of either precedent or outside resources to fall back on. Operating independently of both National Public Radio’s networked affiliates, as well as the rigidly formatted music stations owned by corporate chains like iHeartMedia, they’ve been left to figure out the changed media landscape for themselves. Some have adopted a “keep calm and carry on” philosophy. Others have taken a decidedly different tack.

Indeed, Freedman’s jarring salutation was only a warm-up. He soon segued into disturbing aural collages, no less lyrically foreboding songs from John Cale and Big Blood and tongue-in-cheek announcements (“Tomorrow in Bushwick, the Millennial Bodily Fluids Festival has been canceled!”). For three hours, it was anything but sonic comfort food.

“That’s the nature of WFMU as a New Jersey institution,” Freedman explained over the phone last week. “We do have a real gallows sense of humor, an irreverence.” Which isn’t to say he hasn’t been taking the coronavirus seriously.

After one D.J. with symptoms self-quarantined while others seemed too cavalier about the risks of infection, Freedman felt forced to create a makeshift lockdown. Of the station’s weekly rotation of 60 D.J.s, a self-described skeleton crew of nine, several of whom already live together (and all of whom are pictured on the station’s website as, yes, skeletons running the radio equipment), are now the only ones allowed inside WFMU’s studios, with no more than three ever in the building together. A few more are broadcasting from remote locations, others are pre-recording their shows at home and archival programming fills out the rest of the schedule.

“This is the situation that so many broadcasters dream of!” Freedman said. “You have a global, captive audience, and everyone can share and commiserate their experiences. But it’s not safe to go to the station!”

That potentially sprawling audience isn’t just wishful thinking. New Orleans’s renowned live music scene has come to a screeching halt, but the city’s jazz and old-school R&B-focused WWOZ is more popular than ever.

“I’m looking out my window at the Mississippi River right now,” said Beth Arroyo Utterback, WWOZ’s general manager, speaking by phone from her station’s studio in the heart of the normally raucous French Quarter. “There’s not a soul in sight. Just a single barge. It’s surreal!”

But Utterback can look at the server that feeds the station’s signal online and see that listenership has jumped globally in the past week from 32,000 to 40,000. That’s in addition to the 80,000 people stuck inside and tuning in locally via 90.7 FM, up from 70,000 according to a recent Nielsen study. About a quarter of WWOZ’s D.J.s are coming into the studios to do their shows live, she noted: “We’re still manning the turntables, but everybody gets their own microphone cover now.”

If WWOZ is aiming for, as Utterback put it, “normalcy, as much as possible,” other community stations are embracing the otherworldliness of the moment. At dublab, the electronic dance music-flavored station in Los Angeles, each broadcast day now begins with a new episode of “The Quarantine Tapes”: short phone interviews with hunkered-down artists including the former Black Flag singer and author Henry Rollins and the filmmaker Werner Herzog.

Out in San Francisco, the eclectic KXSF is barely 18 months old, one of a recent wave of newly licensed low-power stations. Born out of a sense of crisis — members of its core team were previously volunteer D.J.s at the University of San Francisco’s station until the school’s administration suddenly locked them out and sold its license to a classical music network for $3.75 million — KXSF is relishing the challenge of staying live on the air at 102.5 FM.

For Carolyn Keddy, one of KXSF’s co-founders, that’s meant plenty of disinfecting wipes, but not a second thought given to changing up her own show’s steady diet of discordant punk and garage rock. Songs like the Weirdos’ bruising “Solitary Confinement” and Noxeema’s no less agitated “Don’t Touch Me” hardly seemed designed to soothe the frazzled nerves of those self-isolating. Which Keddy said was the point: “I know a lot of my listeners live by themselves. They’re bored, they’re scared, or both. This is what’s happening to us.”

Alison “Tex” Clark has been striking a similarly wry note on her show on XRAY, out of Portland, Ore. (107.1 and 91.1 FM). Was her airing of Mudhoney’s fuzzed-out 1988 singalong “Touch Me, I’m Sick” in poor taste?

“Good taste is overrated,” she quipped. Turning earnest, Clark explained that she actually derives as much benefit from doing her radio show as any of her listeners. After years of religiously listening to deafening bands perform into the wee hours, she was diagnosed in 2012 with multiple sclerosis, ending her late-night club-hopping. “Becoming a D.J. at XRAY, being able to take my love of music and my love of being social with people and transfer it all into radio, has become a really important part of my life,” she said.

The emergence of the coronavirus immediately posed a problem for her. “Being on the radio is a very tactile thing: Your face is right up against the mic, you’re touching all the buttons. I’m immuno-compromised. I’m someone without a lot of margin for risk,” she said. So she went online and gave herself a crash course in audio production, quickly buying some relatively affordable gear. The result isn’t quite a home studio, “more like a chair in my bedroom with the mic propped up on the armrest,” she laughed. “But it sounds all right!” Now pre-recording her weekly show, she’s still reaching her regular audience.

Yet, as more community radio becomes prerecorded out of a health necessity, there’s a growing fear that the very essence of radio — the shared, in-the-moment experience between a D.J. and a listener — will be lost. With the flood of podcasts on one side, and the rise of computer-generated streaming algorithms on the other, truly inspired community radio has already been under siege. Will Covid-19 be its death knell?

That has been precisely the concern over the past few weeks at Provincetown’s WOMR, which broadcasts out of a quaint old schoolhouse on the outermost tip of Massachusetts’s Cape Cod (and where I have been a past volunteer). With programming steeped in roots music and folk, the idea of being “on tape” seemed anathema to many of the D.J.s. “There was a worry that it would turn into a Pandora playlist,” explained the WOMR operations manager Matthew Dunn. “Yes, we can talk to each other on Facebook, but there’s something very different, very human, about hearing each other’s voices in real time.”

In the end, with Provincetown declaring a state of emergency, WOMR’s move to a mix of new prerecorded and archival shows was deemed the only responsible action. For now, D.J.s email their files to Dunn, whose own computer feeds into the station’s transmitter, which then blankets the entire Cape on 92.1 and 91.3 FM.

“It’s not ideal,” he admitted, but he’s no longer afraid of WOMR’s programming becoming homogenized. “As long as we have individual, independent, amateur citizens making our content, we’re going to be weird,” he added warmly.

Yes, he continued, “you lose some of the immediacy by pre-recording. But listeners are so grateful that we’re able to do anything. They’re terrified right now!” He pointed to his own afternoon show, where uplifting funk records — already a mainstay — are getting even more spins. “As much as anything else, this is an opportunity to spread joy at a time when people really need it,” he said. “We’ve had some things taken away from us, but radio is not one of them.”