Finding rogue unlicensed HAM station

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natedawg1604

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In my area there is a rogue individual interfering with various VHF & UHF Ham repeaters, it's been going on for at least a month. As I understand it, whenever he speaks it involves profane and/or otherwise abusive language, and he sometimes announces an obviously invalid callsign. Often he doesn't speak, he just keys-up the radio and presses buttons or makes other random noises. So, at this point he is unidentified (other than being male).

In any event, does anyone have any tips for narrowing down the possible location of rogue stations like this?
 

skooterdave

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I would talk to your local Ham club. This is not a new problem to the Ham radio world and perhaps he/she/they/them can be identified and reported to big sister (FCC). Penalties are steep and most good egg Hams are interested in fox hunting, they often have the tools, motivation and time. If he is on a rant listen to the inputs of the repeaters to see how scratchy his is from various parts of the City that you think he is in.

Sent from my LGLS775 using Tapatalk
 

teufler

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in an area, interference is inverse proportional to an active fix hunt group. Unless the fox is mobil, you can df on locating the party. If you are never fox hunted, equipment is miniscle, but the technique is where the skill is at. If the offending party wakes up and finds numerous beam antennas having a convention in their front yard, they understand the jig is up. Most of the time, they give up, you don't hear them anymore, you are now happy, they are happy that they are not looking at a visit from the FCC and possible fines, the FCC is happy because hams police their own. Fox Hunting a mobile is a whole nother game.
 

toastycookies

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In my area there is a rogue individual interfering with various VHF & UHF Ham repeaters, it's been going on for at least a month. As I understand it, whenever he speaks it involves profane and/or otherwise abusive language, and he sometimes announces an obviously invalid callsign. Often he doesn't speak, he just keys-up the radio and presses buttons or makes other random noises. So, at this point he is unidentified (other than being male).

In any event, does anyone have any tips for narrowing down the possible location of rogue stations like this?

There is no such thing as an "unlicensed HAM station".

They are either a ham operator or not.

There are many ways to determine a location of a transmitting station, the easiest would probably be with directional antennas comparing signal strength values.

Do you have other people willing to help out?

A few beams from a few choice locations would be able to narrow it down quite easily enough.

The hardest part would be getting the manpower and cooperation.

Other than that I would just ignore the individual and he will probably get bored quickly.
 

natedawg1604

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Thanks everyone for the tips & advice, I will definitely talk with some other folks about this to see what can be done. I guess the first step is to find at least one location where the subject's repeater input freq. can be heard.
 

SpugEddy

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We used to find the ********* CB'ers back in the day by
driving around until you get a rough idea where he is. Then
when you think you're getting closer, we used to just unscrew
the coax from the back of the radio. When he comes through
your receive, that means you're just about right under his
antenna.
 

cmdrwill

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We used to find the ********* CB'ers back in the day by
driving around until you get a rough idea where he is. Then
when you think you're getting closer, we used to just unscrew
the coax from the back of the radio. When he comes through
your receive, that means you're just about right under his
antenna.


Been there, done that! But it was a So. Cal Gas Company VHF radio stuck on transmit back in the days before Time Out Timers, late 70's. Turned out to be a supervisor's take home car located in his driveway. And his house was in one of those canyons in the hills. Made for lots of reflections to track. Disconnected antenna on the SCG radio in my service truck when the signal got really strong and that did the trick. Still takes a lot of time driving around and figuring which way has the stronger signal, without a signal strength, S, meter.

Today we have better tools.
 
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When living in the Dallas area we held monthly foxhunts, some guys used beams and others (myself included) used Doppler's. With a Doppler you just drove and observed your direction indicator, no need to stop and take beam headings. The Doppler guys almost always found the fox first.
 

KK4JUG

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Several years ago, we were looking for an aircraft beacon. We quickly determined that it was coming from a predominately residential area and there certainly were no downed planes there. Since there was no downed plane, the resources committed to the event were limited: one CAP captain, one EMA officer and myself.

Ultimately, we used an Icom (I think) portable. We removed the antenna and inserted a small plastic and wire plastic bag tie. Then, holding the radio very close, I turned very slowly waiting for the signal to come and go. It was finally pinned down at a local high school. It turns out someone had donated an old air frame for the school to do with it as they wished. However, they failed to remove the beacon and when the would-be mechanics started playing with their new aeronautical toy, they set off the beacon.

A very crude direction finder but it worked great.
 

DJ11DLN

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Some of us used paper clips in SMA adapters on our H-T's a few years back to find a troublemaker who was jacking around with the county Fire Dispatch repeater. Only happened when a certain department was on a run. Turns out he'd been dismissed by them for several things that boiled down to acting like a 12-year-old. And he'd reported his H-T stolen from his car rather than turning it in.:roll:

We "discussed" the situation with him, and he decided to hand over the H-T and charger and to go crawl back under his rock and stay there.:twisted:
 

prcguy

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I have one and it works quite well. It will allow a single person to take accurate bearings from several locations and triangulate a source. Hopefully the source is not moving.

Any other method would involve many people stationed around town and coordinated via phone or secrete frequency. In my opinion its $400 well spent, otherwise you will spend 10X that or more in labor and wasted time.
prcguy


GLOBAL TSCM GROUP, INC. - Radio DF DDF2020T

Can calculate a bearing to a transmitter in less than a second.
 

robertmac

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I've found a couple of problems but probably by pure luck. One was a spurious signal that driving around could tell where the signal strength was greatest. Then when close, removed antenna and bingo. The other was on a local repeater that a Yaesu GM beacon was coming over the air every 15 secs. Again, drive around to find where signal was strongest and headed in that direction. And similar remove antenna and checked input and again bingo. There are Doppler systems now, I believe for reasonable amount so if there is interference a club or individual could purchase and wouldn't take long to find the offending signal. Not sure how effective SDR and computer would be, probably would be useful but suggestion would be for 2 people in a vehicle to avoid distracted driver.
 

Rred

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dawg, not that it is rocket science but unless you get a half dozen hams and some rdf equipment, the typical situation is that everyone is too busy to lend a hand, the rdf equipment costs too much, the fcc doesn't care (no resources, no profit) unless it is a situation like the idiot who was playing with police radios in NYC...the jammer will get bored after a couple of years of disrupting that repeater and that's the only way it stops.

If you can rouse the rabble and get folks up off their butts, and then file a specific complaint with the FCC, sure, you can get this over in a couple of weeks. Good luck with that.
 

robertmac

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dawg, not that it is rocket science but unless you get a half dozen hams and some rdf equipment, the typical situation is that everyone is too busy to lend a hand, the rdf equipment costs too much, the fcc doesn't care (no resources, no profit) unless it is a situation like the idiot who was playing with police radios in NYC...the jammer will get bored after a couple of years of disrupting that repeater and that's the only way it stops.

If you can rouse the rabble and get folks up off their butts, and then file a specific complaint with the FCC, sure, you can get this over in a couple of weeks. Good luck with that.

And the jammer in NYC was found. So others can be found.
 

ElroyJetson

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DO NOT ASK ME FOR HELP PROGRAMMING YOUR RADIO. NO.
I installed a variable attenuator between antenna and radio and kept adding more attenuation as I got closer toward the unwanted transmitter. Eventually I narrowed down the location to a single building while using a shielded dummy load on the radio to make it as deaf as possible. Given that the building was in a "secure area", I just turned over my findings to my boss and let HIM deal with notifying the FCC and maybe some unnamed government agency officials that they had a troublesome radio issue within that facility. It did get taken care of, don't ask me how, exactly. I don't really know and it wasn't my place to find out.
 

TheSpaceMann

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We used to find them with small loop antennas! Just triangulate the signal from 2 points of reception.
 

Rred

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"And the jammer in NYC was found. So others can be found."
ROFLMAO.
You're absolutely right. All you need, is to have the entire NYPD pissed off at you, big time, and a state senator motivating the FCC. Without that? Jammers in the NYC metro area typically go for years without being found or punished. Same thing elsewhere. If the jammer hadn't pissed off the NYPD, he'd still be on the air. NYPD policy on police radios is fairly simple: If you're not a cop, and you touch one, it doesn't matter why. You're going down. Zero tolerance.
 
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