Moments after people began using radio waves as a mode of communication, jamming or deliberate interference was invented. In the early days of radio communications, patent owners and radio technology manufacturers were in a constant battle to have supremacy over the airwaves.
The early days of radio business, companies that manufactured radio equipment also trained its operators and supplied trained operators along with the radio equipment when they sold radio transmitters to clients.
At some point, it was a written policy that operators trained by one manufacturer were forbidden to communicate with operators trained by another company in order to maintain some sort of supremacy over the airwaves. Subsequently, fears competition between radio manufacturers was the source of what were understand as radio signals jamming. In those days, communications were performed in morse code and more often than not, random “Dits” & “Dahs” were transmitted over ongoing transmissions in an effort to discredit the quality of service offered by these radio companies and punish operators for pledging allegiance to a particular radio service company. infamous “jamming” events between company operators such as England’s Marconi and Germany’s Telefunken were at the heart of some of the first radio signal jamming practices.
The World Wars: Commercial jamming technics quickly evolved into military strategies to undermine opponent’s attempts to use radio waves as a communication technology. From World War I (1914) to the Iraq War (2003) and every wars in between, radio signal jamming has been a constant throughout the years.Jamming
Over a century later, things have not changed much, but technology has. Radio manufacturers no longer train and supply operators, but radio signal jamming is still very much present in our everyday lives, at least, in the lives of Amateur Radio operator. Militaries have much to gain in mastering the art of radio signal interference or jamming as many countries still use the airwaves as their primary method of communicating with troops. I have personally encountered the frustration of having some of my microwave broadband networks go down because of a few high tech firm nearby testing jamming equipment being sold to the military. Unfortunately, I just happened to have one of my retransmission node too close to their testing laboratories. Clearly, they we’re illegally jamming public ISM bands and it took me over a month to locate the source of the jamming signals. Other than a few strong words with one of their public relation person, I had little chances of winning any fights against this “Military Jamming” high-tech firms.
Jamming might render completely inoperative opponent’s mode of communication, it may also be used as a propaganda strategy to lower the confidence levels of opponent’s troops. The evolution of radio technology allowed for the creation of counter measure methods, not only improving on scrambling the message being transmitted, but also allowing message to be transmitted on several frequencies, hopping from frequencies to frequencies, therefor bypassing jamming signals. But those are subjects for another topics I’m working on.
I cannot listen to Amateur Radio signals for an hour without witnessing some form of jamming or interference deliberately caused by Amateur Radio operators (Also referred to as QRM). While most operators I listen to have over and above ethical conducts on amateur bands, there are the relentless few who make it their hobby to jam other signals. What are the reasons behind these deliberate interferences ? Politics, religions, opinions, jealousy, contempt, spite, hatefulness or plain old bigotry are all behind acts of interference.
There is quite a palette of jamming types, none of which happen on any particular bands. To the contrary, I’ve heard jamming signals of all bands, all frequencies, in and out of Amateur Radio allocated frequencies. It’s everywhere and neither the FCC (United States) and Industry Canada appear to have much resources available these days to track down and dismantle jamming stations.
Here is an example of one of the most famous jamming which happened on 80m band, involving what was called then “The Marconi Net” which operated around 3.842 Mhz:
Marconi Net Jammer Sample:
A good example of deliberate interference. (Source: Youtube)
The host of “The Marconi Net” was literally peppered, often for the duration of his net, with endless inferences composed mostly of music broadcast, derogatory and obscene comments, cartoons noises and sometimes, as in this example shows, an endless loop promoting “Macaroni”. What is truly baffling with this example is the fact that the host relentlesly endured such abuses night after night for years, occasionally winning some battles, but was it worth it? If you enter into a communication realm and get plastered by the village idiot, wouldn’t you get a hint to move on?
There is another type of phenomenon which I sadly noticed on the bands, operator wars! Yes, where there are men, there will be wars! One of the most infamous war going on involves a hand full of Canadian and American operators exchanging foul language and accusations over the upper portion of the 20m band, specifically, on 14.313 MHz. I was dumfounded when I assisted at my first heard one of these war sessions. A Canadian station monologued for over 45 minutes and probably used the “F” word a few hundred times during this transmission. Here’s a sample;
Wars on 20 meter Sample: (Source: 14.313 Mhz).
Warning: Foul language used at perpetuity!
Update: It didn’t take long after I wrote this article that the culprit identified in the clip above started attacking me on his internet blog. It just shows how much narcissist people try to blame their problems on others.
While I was blogging this article, I decided to tune on 14.313 MHz out of curiosity… lo and behold, there he was again, broadcasting another monologue to his nemesis. This particular group warfare has be going on for many years and you can sadly listen to is almost everyday, pending propagation on 20m. 14.313 MHz is the proverbial landfill for 20m. Seems like everyone without a shred of decency enjoy broadcasting their 2 cent’s worth in the form of music, sounds effects, recordings, propaganda and hate messages, but the bottom of this iceberg appears to be revolving around a few operators.
The clip above is a clear example of the total indifference or acute powerlessness of broadcast authorities. All out wars are not limited to Canadian or American stations. I frequently witness international verbal wars between operators who, for some reason or another, decide to duke it out in their relative native language. What often triggers these international exchanges is near frequency proximity transmission. A powerful station deciding to call “CQ CQ CQ” one MHz away from an ongoing QSO is enough to ruffle some feathers.
When I first had the guts to broadcasted my callsign on the local 80m call frequency to introduce myself, I was greeted with by the “regulars” with condescending comments; “Your signal is weak, The antenna you use is a toy.” and so on. Don’t worry, if you are new at this, you’ll eventually meet those guys and discover how insecure they really are. And if you do and don’t like what you are hearing, move on. The hobby is too much fun to be dampened by minorities. Funny enough, the nicest people I’ve ever met was on Amateur Radio.
I believe that where ever you will find men, you will find men behaviour and men stupidity. Upon witnessing deliberate interference, I recommend you change frequencies or turn off the rig. Don’t encourage anyone by making comments or joining the wolf pack. If the jammers knows he has an audience, it will fuel his efforts to do more. Besides, don’t you value your time more to do something better than listen to someone ‘s stupidity? I do.
Before I got my operator license, I used to listen to an Internet stream of a Los Angeles VHF repeater. This repeater “W6NUT 147.450 MHz” (Known for being home to Hams nobody else wanted), was a jaw dropping experience.
Have a listen: Warning Foul language used.
I was sad to see how W6NUT reflected negatively on the hobby with pure ignorance, racism, hate and defamatory comments. I simply tuned-out after a while. Although bad Amateur operator behaviour is everywhere, VHF-UHF bands simply seem to have more. Local Amateur Radio clubs often have to deal with deliberate interference on local repeaters and it’s an ongoing battle. Jammers are often rogue club members which makes it that much more difficult to catch them in the act, but sometimes, they do.
In conclusion, there is little you can do to avoid deliberate interference. If you talk on the radio, someone somewhere will probably not like what you are saying and create interference on your QSOs. The only thing you can do is to ignore them, do not acknowledge they interference or presence. Change frequency or channels. They will eventually go away. As for Amateur Radio wars, you might find it entertaining to listen to “On the Air” verbal wars, I don’t. My recommendation is to stay away and never to take sides. You will avoid getting caught in the crossfire. Some people are just impossible to reason with and you certainly don’t want to waste your time trying to reason with them.
I’m writing on an article discussing the various types of interference technics and countermeasures as I find this subject somewhat fascinating. Don’t go thinking interference warfare is something of the past, au contraire my friends, more and more technologies today are relying on radio frequencies to operate and understanding how they work and how they can be jammed gives makes this hobby much more interesting.
Here are a wide variety of deliberate interference (jamming) found outside Amateur bands.
North Korea Jamming sample;
Popular Pirate Radios in the UK;
Mossad jamming a number station;
The infamous Russian Woodpecker Radar sometimes causing havoc on HF frequencies;
And finally, watch this interesting documentary about the
legendary UVB76 (MDZHB) Russian station and number stations;