But what police are calling a public safety measure, scanner hobbyists are describing as a blow to transparency. Now they're asking plaintive questions about whether it portends the end of a pastime once incubated in science clubs and Scout groups.
"Who's to blame? Who caused it? . . . What's the future?" despaired one enthusiast in a YouTube video shot amid his scanners and wires.
"Is our hobby dying?" lamented one chat thread on RadioReference.com.
"The easy days of scanning are gone," prophesied one post on eHam.net.
In the Washington region, the keeper of the scanner code, and a source of stability in these turbulent scanning times, is Henney - director of the Capitol Hill Monitors group, publisher of the Capitol Hill Monitor periodical and author of the 534-page Washington-Baltimore Scanner Almanac. He spends his days at home now, tending to his ailing 87-year-old mother, planning annual regional scanner gatherings, listening to the channels he still gets and tweeting updates in the staccato voice of a just-the-facts-ma'am newsman. Meanwhile, he apportions blame for the possible collapse of his obsession.
High up on the list: Radio Shack.
There was a time when Henney was getting started - just a boy and his scanner, given to him by his father as a birthday gift - that Radio Shack was a haven for enthusiasts like him. But then the company pivoted from the radio to other electronics, and the sense of disillusionment in the scanning community was great indeed.
"Abandoned," Henney mourned. "Many of us felt abandoned by Radio Shack."
It was only the beginning. Police and other public safety agencies started switching to a more complicated trunked radio system, requiring the purchase of additional equipment and sending the hobby's expenses soaring. Then came the terrorist attacks of 9/11 and with it increased concern over securing communications. More recently has arrived the next generation of Americans, less enamored of the radio waves, preferring social media and newer technologies.
"I'm not saying enthusiasts my age do not exist," said Kenny Lorber, 27, who also volunteers with the Montgomery County Park Police. "But they are definitely dwindling."
So, too, were the number of people going to Henney's annual scanning meetings, plunging from a height of roughly 50 people in the 1990s to fewer than half that number these days. Even longtime scanning buffs started dropping out.
"In November, I turned 80 years old," said Willard Hardman, who wrote the scanning almanac with Henney. To him, scanning is no longer "cost effective."
"As a result," he said, "I sold or gave away my equipment and left the hobby."
Those who have left, and those who aren't willing to get going at all, are missing out on what scanning buffs describe as an unfiltered, fully texturized reality - undiluted by information gatekeepers such as journalists and spokesmen.
"This radio traffic really gives you the pulse of the city and makes you realize how many stories are not being told," said Luke Berndt, who got into this when he was living near a Washington fire station and his daughter kept wondering where the trucks were going. The answer, it often seemed - to tend to an overdose. This was an event, he learned, that occurred thousands of times every year in the city but was rarely reported.
This plumbing of a city's underside, accessing knowledge few have - all of it mingles to yield an intoxicating feeling that has kept Henney, who supports himself with rental properties in Delaware's Rehoboth Beach, coming back for more.
He now stood for lunch. He buckled one scanner onto his belt. Then he put on a black vest with big cargo pockets. Into each, he fitted a scanner. He started for the door wearing five or six scanners and got into a car fitted with two extra radio antennas and equipped with a catalogue of radio channels.
"What if something big happens and I miss it? I don't like to miss stuff," he said by way of explanation as he drove to a local restaurant. There, he set up shop at a side table, arraying his scanners before him. Sometimes people look at him a little funny, but he rarely pays attention. His focus is on the news that could happen at any moment.
So far that day, there had been only one bit of news that he said "rises to the level of a tweet."
It hadn't been big. Just an ATV crash near Camp Springs, Maryland, with "serious but hopefully [nonlethal] injuries for the ATV rider," as he'd reported. But it had been big enough: Enough for the public to know. Enough to distract him from the feeling that one day he may not have any more news to share at all.
Back at his house an hour later, he saw no one had followed up on his tip. But maybe someone would with the next one.