FM Radio disturbances

I live in the south-western Canada, in a smaller town. In this area we have 3 radio stations; today we had at least 15...

This morning when I woke up the power was off, it had gone off at about 4 am prior (yes prior) to a heavy rainfall; it stayed off for about 4 hours.

When I left my house around 11 am I turned the radio on in my truck and found I was picking up an unknown station, so I changed the channel only to find another station I did not recognize. I skipped through the radio stations and discovered I was receiving stations from as far away as new mexico! Crystal clear!

How is this possible? I have witnessed such phenomenon with a CB radio, where radio waves bounce off the ionosphere, but these were never clear and always full of static.

I am currently toying with the idea that maybe there was a solar flare recently that could cause such a dramatic effect on FM radio? Maybe even HAARP technology? Whatever it was, I have never seen such a thing in my 28 years on this planet.

Any ideas, insights, or corroroborating stories are greatly appreciated!

It's rare in the north but the cause is Tropospheric Ducting.

Tropospheric Ducting (TrD)
...is an abnormal condition. An inversion has formed at a much higher level above the ground...the vast majority of duct-producing inversions lie between 450 and 1500 m (1500 to 5000 ft)..with a few between 1500 and 3000 m (5000 to 10,000 ft). These inversions are not formed due to nighttime radiation/cooling..but rather because of some other weather phenomenon (high pressure subsidence aloft, warm frontal boundary, cold frontal boundary, oceanic or lake inversion, Chinooks, etc.). Because of this..ducting can occur day or night (though it strengthens at night)..is not usually influenced by terrain (the exception being large mountain chains like the Rockies)..and from a DXers point of view is usually either uni- or bi-directional. In fact..typical ducts are sharply directional. Signals refract off of and also travel along the inversion..thus the analogy of a duct. Strong ducting can result in super-refraction where signals are bent so far in a downwards direction that they actually hit the ground and reflect off it, only to bounce of the top of the inversion again and so on. Distances are theoretically unlimited. One large area can have multiple ducts going on simultaneously..but they are usually parallel paths. It is possible in a very strong high pressure system to have large areas of ducting creating multi-directional openings. These are the rare "blockbuster" openings that bring signals great distances and cause havoc with interference. They are most common over the oceanic areas in the tropics and sub-tropics.

Source

Hope that Helps

I remeber working offshore in the Gulf Of Mexico and hearing houston and Miami USCG talking on VHF 16 which is also FM but higher in freq than broadcast FM. It can sometimes be confused with skip for the non HAM crowd.

[edit on 29-6-2010 by SWCCFAN]

reply to post by SWCCFAN

Wow, thanks.

Part of the research they do at HAARP is to research tropo ducts, we'd like to be able to produce them from point A to point B on demand.

So while what you heard wasn't a HAARP effect, they'd like to be able to do that one day, so they can take HF comms from here, to say, Stuttgart, without anyone being able to hear it between or needing a satellite for a relay.

reply to post by SWCCFAN


this thread was a good exaple of how ATS works..someone has a question about something they cant or dont understand..and then..BAM! someone from our distinguished community comes along and shares a little of thier specialty..no fluff..

good stuff


~meathead

In the two-way radio community, they refer to this as E-Static Skip, a bizarre but completely natural electrostatic condition of the Ionosphere that propagates relatively weak radio signals over thousands and thousands of miles. I live in the Smoky Mountains of the Carolinas, and using a common Citizen's Band transceiver, for example, I've talked to Ontario, Canada, South Texas and Puerto Rico within a span of a few minutes, although my radio is only capable of perhaps 10-mile transmissions under normal circumstances.

Radio enthusiasts eagerly anticipate these conditions; however, for some weird reason, the Federal Communications Commission has made it ILLEGAL to talk long-distance using E-Static Skip.

Yes, we know it's a completely natural phenomenon, but we're going to prosecute you if you take advantage of these unique conditions!

Crazy.

— Doc Velocity





[edit on 6/29/2010 by Doc Velocity]

Wow, when I read this title I thought I had found the answer to some weird FM issues I've been having. Maybe someone reading this thread can tell me what's causing my own issue since I don't have enough posts yet to create a new thread ---the topic IS FM radio disturbance.

I have just the opposite issue of the OP. A couple of days ago---3, I think---I got in the car to go to work and after a minute realized that the radio was just playing some low static. I usually keep it tuned to NPR and the local station sometimes has little dead spaces like that which last a few seconds so I didn't think a lot about it. After a couple minutes I went to change channels and discovered that ALL the FM stations were gone.

Since I live here at ATS, lol, my first thought was "Hmmn, has some S HTF somewhere? Wonder if the TV channels are out too..." Of course my second, more logical thought was "Crap, my radio quit on me. No more NPR." I switched to AM, which worked just fine (except for the fact that there's not a thing I want to listen to.)

So, I got home later and asked a couple friends if their radios were working properly just to make sure it really was only mine, and everyone else's was fine. And that would be the end of the story except---

The next day, I took my MP3 player with me, since it has FM radio too, and it was fine for about an hour, then lost all of the FM channels too. Go figure. Everything else about it works fine, but no FM. Haven't touched the radio on the house stereo for fear I'll somehow fry it too.

Any ideas?