Why would someone jam RF communication signals?

I just read this news story on someone who used a couple “electronic signal-jamming devices” to jam WiFi, satellite signals, and cellular signals in their neighborhood.

Why would someone do this? What would be their goal? I even found a company that sells such devices.

I don’t get it.

Plenty of reasons to jam radio communications. Most of them illegitimate.
Legitimate reasons include jamming cellular phones in prisons, wiping out remote control capabilities near sensitive events and people (I would imagine there is a significant jamming capability anywhere the POTUS goes).
When mobile phones first became a big thing I remember discussion about deploying jammers in cinemas and theatres. The answer here was that this was totally illegal and would remain so.
Illegitimate reasons for jamming abound. Jamming police radios could be useful for some criminal activities, jamming and spoofing GPS has all manner of nasty uses. Long distance truck drivers use jammers to disable tracking. Military reasons for jamming of GPS are significant. Jamming anything really.
The linked news article is probably just some idiot with an antisocial bent. Very hard to ascribe motive to idiots. Maybe they thought that if they jammed the local 5G signal they could avoid getting Covid-19.

Wow–that one short article had 5 large ads that bypassed my ad blocker.

I suspect severe misunderstanding of one sort or another. Probably have no idea that they are putting far more waves of those frequencies into their immediate environment rather than eliminating them.

Need some sort of ad jammer.

We used jammers all the time, back in my former line of work. The idea was to prevent RF-command detonated IEDs from functioning. But, that was a legitimate purpose. I guess “legitimate” depends on who’s side you’re on…

After reading that article, I would tend to agree with @Francis_Vaughan, but I know that equipment isn’t cheap. Someone jamming signals surely for idiodic reasons is gonna dole out some cabbage for the capability–and is gonna get caught. My guess is that s/he was up to nefarious purposes, thought of by this quote:

Police said the severity of the signal jamming in the immediate area resulted in the loss of WiFi, a satellite signal and cellular signals along with a county radio communication tower located nearby.
(Bolding and italicization by Tripler)

County emergency communications representatives advised police that the electronic interference adversely impacted all southern Santa Clara County emergency radio operations, including that of Morgan Hill’s police and fire departments, Emergency Medical Services and the Santa Clara County Sheriff’s Office. The jamming also affected radio signals for the Gilroy police and fire departments, Cal Fire and other agencies.

So, maybe a local pickpocket who wanted to delay responses? Would-be bank robber that wanted to disable the bank’s VOiP phones? Wealthy-eccentric crackpot afraid of 5G?

Tripler
The OP’s article did not mention the presence of tin foil hats.

The jammer was in his own home. Unless he specifically purchased the house because it was near a radio comms tower so he could disable it, or he was the victim of a Adventure of the Red-Headed League-level of criminal scheme, I think the idea that it was part of some sort of criminal plot to disable county emergency services communications is vanishingly unlikely.

Far more likely,

Or anti-social curmudgeon who disapproves of all this newfangled wireless nonsense. Or anti-social troll who thought it would be funny. Or, perhaps most likely, some combination of the three.

Some guy installed a cell phone jammer in his car so those driving around him would not be on their phone while driving near him and thus paying better attention to driving and not be distracted. It made the news a few years ago. They caught him because the cell company noticed the disruption to their network and working with the FCC (IIRC) and law enforcement was able to find the guy who I believe got massive fines and perhaps jail time.

I see your point, but will throw in another angle: the dude’s a moron if he left it on all the time. If he’d done “spot jamming” over short, discrete periods of time (say, only during his crimes), then that would imply intent, and thus nefariousness. The article doesn’t say one way or the other, but if RDF was able to locate the device, then he was leaving it on for extended periods of time.

Wealthy-eccentric crackpot it is!

Tripler
A self-defeating crackpot: using RF to jam ‘harmful’ RF.

People who don’t want their employer tracking their vehicle sometimes do it (or course the fact that that the tracking isnt working may itself stand out). Sometimes they get noticed driving on the edge of airports.

I had a friend that believed he was being followed. He had a half decent case and I decided it may be true so I lent him a tool that I have that disallows use of GPS nearby. After a few weeks, the threat was over and he returned the device.

Bolding by Trip.

Huh? What’s with the airport edges?

Tripler
Airports need RF comms too. . .

If they’re driving on the edge of an airport, their jammer may interfere with airport communications systems, which is likely to be noticed.

Oh, I see what you mean now. I mis-read your post, due to attempted multi-tasking this morning. :man_facepalming:

Tripler
My signals got crossed.

Just popping in to say that sometimes the answer is mere irrationality, anti-social behavior, and/or, 'because I can." A career in local law enforcement taught me that much of the inexplicable is just that - there isn’t a “logical” reason or something a reasonable person would see as a benefit to the malefactor.

Many years ago there was a news article about the president (then) if Pakistan (Zia?). About half a minute after his convoy drove over a bridge, a bomb went off blowing up the bridge. Speculation was that the bomb was triggered by a cellphone call, and his vehicle had a jammer - so the call was delayed until the car was off the bridge.

Before cellphones were a big item, I recall some article about how when the US president visited a city, sometimes electronics in the local neighbourhood around where he was would act up. Garage doors nearby would, for example, randomly open and close. Presumably the same idea - active jamming of any remote control devices to thwart detonation of bombs, for example.

I remember too the news article about the guy jamming signals on the expressway - IIRC it was on one of the routes into Washington DC; the guy wanted to keep those annoying distracted drivers from being stupid around him. However, stupid is as stupid does. He had a predictable route and time. When complaints came in, it didn’t take the phone company and the FCC to figure out what was happening and start looking for the cause. (I never saw a follow-up on it what his punishment was.)

MY dad told me the story of back in the early 60’s, back when every annoying jerk had a transistor radio blaring on the public beach. This was the days before FM or cassette tapes, so always AM. A local hobbyist rigged up a battery-operated static generator unit to drown out the signal of the AM radios, so people in the area would turn off their radios and he could enjoy a quieter day at the beach.

I would think drivers around him would be looking at their phones, trying to figure out why they do not have a signal.

Earlier this summer I was having some trouble with my home WiFi. I would have my phone sitting on my desk during the day while I was working, and out of corner of my eye I’d see it pop up a message “WiFi disconnected” and I’d see the status bar switch from WiFi to 4G, then a few seconds later the WiFi would reconnect. And it would do this repeatedly throughout the day, every few minutes for an hour or two, and then it would be fine for a few hours then it would start again.

After confirming that it was happening on all WiFi connected devices in the house (not just my phone) I scheduled a service call from AT&T, assuming it was their equipment that was flaking out. A guy came out, found some issues with the wiring going into the box on the side of the house, replaced our gateway/router with newer equipment, and said we should be fine. That afternoon, a few hours after he left, it started again.

This went on for about six weeks then stopped as suddenly as it had started. Now, reading the article in the OP, I wonder if it was some knucklehead in our neighborhood screwing around with a jammer.

That was my thoughts about this when I first heard it.

There was some discussion / conspiracy theorizing a few years back that hotels were jamming 3g/4g signals so as to make their (overpriced) wifi the only option. 30s of googling didn’t find any resolution to this - just the original articles suggesting it might be happening - so I suspect it wasn’t really the case.

That’s setting aside that it would be illegal, per the FCC for someone not specifically authorized by the feds to do so.