A Radio Question - Whats the difference between AM and FM?!


Question: A Radio Question - Whats the difference between AM and FM!?
What is the basis on which operators decide to broadcast either on AM or FM frequency!?!?Www@Enter-QA@Com


Answers:
AM - amplitude modulation - AM radio ranges from 535 to 1705kHz (kilohertz, or thousands of cycles per-second of electromagnetic energy)!. These are the numbers you see on your AM radio dial, and some stations seen to endless repeat when they promote themselves!.

AM radio stations the ground wave doesn't go very far!. This means numerous stations can be put on the same frequency without interfering with each other — assuming they are far enough apart!.

The problem arises — if you want to see it as a problem — with the sky wave, which can end up in other states and provinces, or even in other countries!.

The ionosphere is much more effective in reflecting these radio waves at night!. (Incidentally, technically, it's refracting, not reflecting, but the effect is somewhat the same!.)

That's why at sunset most AM radio stations in the U!.S!. have to:

* reduce power

* directionalize their signal (send it more in some directions than others),
or
* go off the air (sign off until sunrise of the next day)
This may explain why your favorite AM radio station goes off the air at sunset, or becomes much harder to hear (because of reduced power)!.



--------------------------------------!.!.!.

FM - frequency modulated - they are on a higher frequency in the RF spectrum!. (The name RF, for radio frequency, was obviously named for radio, but when TV came along they just stuck with the name)!.

The FM radio band goes from 88 to 108 MHz (megahertz, or millions of cycles per second)!. Again, you can see these numbers on your FM radio dial!. FM stations must be 200kHz apart at these frequencies, which means that there's room for 200 FM stations on the FM band!.

But, unlike AM radio stations, FM stations don't end up being assigned frequencies with nice round numbers like 820 or 1240!. Thus, an FM station may be at 88!.7 on the dial!.
You may have noticed that FM stations don't reduce power or sign off the air at sunset!. Because of their higher frequency ionospheric refraction doesn't appreciably affect FM or TV signals!.



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They run on different frequencies and AM is an older and less commonly used station!. FM is newer and i think it's easier to getWww@Enter-QA@Com



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