hai pl explain what is FM Radio and how it works.?

Answer 1

Beyond the technical, I think your question deserves a better answer. A less technical answer. Oh, OK, technically, FM is a bandwidth. Stations transmit a signal on a frequency from around 88 to 108Khz and your device (a radio) picks it up. It's limited to "line-of-sight" meaning buildings, mountains etc. will get in the way and so its reach is limited. But the quality is great. That's FM. Frequency Modulation. Now that wasn't so hard - though still a bit technical.

But in the more Karmic sense: What FM really is - is the band that saved radio. Starting around 1970, just as today, people were becoming bored with radio, which was predominately on the AM band. (FM existed but was reserved mostly for non-commercial uses).

The music was stale and formatted. You would actually hear "Sugar, Sugar" by The Archies followed by Simon & Garfunkel and into The Partridge Family, The Carpenters, James Brown, Led Zeppelin... I know, hard to believe, but that was Top-40 back then; with a Glen Campbell and occasional Merle Haggard thrown in. The DJs were too talkative - and there were way too many commercials to deal with. Hard to imagine with today's very narrow niche-oriented stations. Well, except for the commercials part. Greedy buggers then - greedy buggers today.

But it had been the only game in town. The AM band has a more powerful signal, but the quality is junk - and there was no stereo available at that point. Then, stereo eight-tracks and cassettes and reel-to-reel recorders became inexpensively available and radio began to lose listeners, just as it is today with the advent of iPods, Internet and Satellite.

People lost interest in AM radio. Stations had fewer advertisers, things were going downhill fast.

Guys were coming home from Vietnam with incredible systems bought at ridiculously low prices while on R&R in Hong Kong or from their PX. Then the Japanese, who have always known a good thing when they heard it, started sending these systems, equipped with AM AND FM dials into the US. And the music was beyond Hi-Fi, it was STEREO. And not available on the AM band.

Suddenly the geniuses who owned the stations realized the public wanted better fidelity. These station owners thought to themselves, "Well we've got this FM signal we only use for elevator music (technically called The Schulke Format, invented by Jim Schulke), let's give it a try."

With all of this could come a re-invention of the medium. Marketing, branding, salvation!

Thus it started, originally with "progressive radio" (album cuts). And all of a sudden listeners could listen to the entire Allman Brothers "Live" Album, in stereo, on big ol' Pioneer CS-88 speakers from an Army PX. It was heaven in a box.

Listeners started buying tuners that would pick up FM signals. AM stations went south, fast - but eventually came back with talk and sports. Advertisers started buying commercials again.

Owners smiled, advertisers smiled, listeners smiled. Then came the Internet; a bunch of investors got together to launch a couple of satellites and beam music down to earth, Scottie; and Steve Jobs thought of a way to save his company.

But that's a story for another day.

-a guy named duh

Answer 2

The first answer you received has a URL that may shed some light on your question.

I'll try and answer your question as non-technically as possible. In either an AM or FM transmitter, if there is no sound being transmitted, you have a signal from each which is transmitting on only one frequency. You couldn't tell which is AM or which is FM.

If you were to play a single note into each transmitter (say A-440, a standard note in music), a big difference would appear. The AM signal will get stronger and weaker 440 times each second. How much stronger and weaker is dependant upon how loud the volume is. This is called modulation. AM stands for amplitude modulation and the amplitude (strength of the signal) varies along with the note (or music).

With FM, that signal does not get stronger and weaker; instead, the darn *frequency* actually changes. Up and down with the note. How much the frequency changes is dependent upon how loud the volume is (and hence, *frequency* modulation).

The two signals are decoded very differently, but the crux of the situation is that AM signals vary in *amplitude* and FM signals vary in frequency.

AM is pretty much standardized. 100% modulation is defined as when the amplitude of the signal just reaches zero when maximum audio is applied. Apply more audio and you have severe distortion.

With FM, it isn't quite as simple. More audio, more deviation. The problem here is that eventually the frequency change (deviation) of the signal is too much for the decoding process at the receiver and you get distortion. There are various FM services, each with different definitions as to what defines 100% modulation. This is set by the Federal Communications Commission in the United States and this allows proper communication within each service.

Hope this helps ;)


Best regards,
Jim

Answer 3

Radio that works on the principle of Frequency Modulation (FM).

Here the amplitude of the wave is unaffected. So, the noise level is low and the sound-quality is good.

Answer 4

fm radio is radio stations that play music from 88.1 to 107.9



ps i hav no idea how it works

Answer 5

i dont now search to yahoo

Answer 6

Why don't you just look it up on Yahoo!?

Answer 7

http://en.wikipedia.org/wiki/FM_Radio