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![]() FM Radio "FM" radio is relatively new on the scene. While experiments began as early as the 1930's, it did not come into widespread usage until after the Second World War. Canada's first FM radio station went on the air in 1947. Like the term "AM radio", what we know as "FM radio" is a bit of a misnomer as well. FM is short for "frequency modulation". "FM" is not only used for radio broadcasting, it's also used for the audio portion of television broadcasting, two-way radio communications and even for things like "baby monitors". The "FM radio" band in most parts of the world occupies the spectrum between 88 and 108 Megahertz (MHz.) There are some slight differences in some other parts of the world. For instance in Japan the band runs from 76 -90 MHz. In the former USSR and some Eastern European countries it occupied the spectrum between 66 and 74 MHz. These frequencies are all in the "VHF" or "Very High Frequency" part of the radio spectrum. FM radio is much less prone (but not immune) to interference from human made devices and from other stations occupying the same frequency. If two close-by stations occupy the same frequency you will always hear the "stronger" of the two. Although if you happen to be in an area where signals are "marginal" you may hear different stations fading up and down. It's also possible to "multiplex" FM radio signals to enable stereo sound. Nowadays virtually all FM radio stations in Canada (aside from a few low-powered CBC Radio One transmitters) broadcast in stereo audio. Because the FM radio band is in the VHF spectrum, signals will normally travel about 200 KM at best from the transmitter site. However, if you are at a relatively high elevation in relation to a transmitter tower you may find that signals will travel a little further. If you're sitting in a car travelling along the highway you'll find that as you climb a hill a signal will get stronger. But, as you go back down a hill you may end up losing the signal completely. There are some circumstances where FM radio signals will travel much further than normal. One such circumstance is during periods of changing weather patterns where "tropospheric ducts" will form creating a radio "pipeline" between one location and another. This most frequently happens in the summer months in southern Ontario usually in the evenings and early in the morning. Another phenomenon that can create long distance FM radio propagation is during periods of "sporadic-E skip" where signals literally skip off of the E layer of the ionosphere. Sporadic-E skip is related to solar weather and most frequently happens during the week or two before and after the winter solstice and for a month or two before or after the summer solstice. Periods of E-skip don't last nearly as long as tropospheric ducting and usually will most affect frequencies at the lower end of the FM radio band. However during "E's" signals can travel much further than during "tropo" openings. Here in southern Ontario, it's not uncommon for there to be an "E-skip" opening into central Florida. Not nearly as frequent are "F2" openings where signals can travel for literally thousands of miles. This will happen during periods of high solar activity at the peak of the eleven year sunspot cycle. The last "peak" of the cycle was in the 1999-2001 period. As of this writing we're still heading towards the bottom of the cycle. Again, there are radio hobbyists who take advantage of all of these "freak" types of radio propagation hoping to "bag a new one" for their "collection". They're known as "FM DX'ers". Because both TV and FM radio occupy similar parts of the radio frequency spectrum most FM DX'ers are also TV DX'ers! Here are some links that you might find helpful on "FM DXing". Even if you aren't a radio hobbyist these links can help you with improving your "normal" day to day FM radio listening. Ontario DX Association World-Wide TV FM DX Association Mike's TV and FM DX Page FM DX Resource List DX Radio - (UK site) Bill Hepburn's World-Wide Tropospheric Ducting Forecasts TV/FM Propagation Logger on "DX World" top As you can see from the list below, the FM radio band in and around Toronto is very crowded! What stations you'll hear will depend very much on where you are! TORONTO AREA FM RADIO STATIONS
* Linux unfriendly audio streaming. ** Uses "Right Now Radio" service to stream audio. This service advertises itself as "Radio Without Limits". Well you have to register on the site to listen to the audio stream. Sounds like a "limit" to me! Oh well...just login as "y@y.com" and enter the password "111111". *** Audio stream offline when last checked Streaming Media formats change all of the time and so alot of this info is really hard to keep up-to-date. Please report any errors, ommissions or updates on this list to feedback@ve3sre.com ![]() ![]() feedback@ve3sre.com |