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> why does fones only have FM not AM?
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hello can someone tell me why is that most fones have FM not AM? I think the signal of AM much better. What's the different in FM and AM?
thanks
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Posted: 2005-08-27 09:09:19
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I can't remember the details but FM has a fixed Transmission radio spectrum. But unlike the AM frequency it has a Crest and trough spectrum(or a wavey transmission method)>>..So i guess that explains why my gas plane and nitro car have a AM frequency crystal.??
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Posted: 2005-08-27 09:16:35
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I think i see what you're driving at, SirH, although i'd agree that AM would be great... It'd allow me to get BBC, VOA, WRN, etc...
This message was posted from a Nokia
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Posted: 2005-08-27 09:27:47
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Isn't AM sonically inferior to FM? That might be it!?
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Posted: 2005-08-27 09:53:00
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Hi,
the reason is 90% economics and 10% technical.
AM = Amplitude Modulation
FM = Frequency Modulation
I won't bore you with details, except to say they are two different techniques for radio transmission. To also inlcude an AM reciever would require extra circuits (always a problem for a phone) and add extra complexity to the user interface (must be able to switch between AM & FM).
Now before you jump all over me to point out the extra curcuits & UI complexity is tiny, I know. Remember I said technical was only 10% of the reason.
The main reason is economics. All over the world, FM is the main mode of operation for commerical radio stations, mainly because it is more robust than AM (less influence from interference), thus providing a better sound reproduction. The exception is the US, where FM is the main mode in urban areas, but AM is still very popular, especially in rural areas where AM has better range than FM.
Thus SE figure it is enough to only support FM as this is good enough 90% of the time and besides, radio is a "gimmicky add-on feature" to the phone and not its main function.
Regards,
/Mike B.
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Posted: 2005-08-27 10:31:39
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And the added circuit would make the phone quite a lot bigger. The same reason mp3 players don't have AM radios.
This message was posted from a T630
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Posted: 2005-08-27 11:58:07
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It's simply down to the size of the antenna required. The broadcast wavelengths involved for AM transmissions are typically very much longer than those used for FM radio. The longer wavelengths demand bigger aerials. If you've ever taken a radio apart that has an AM receiver in it, you'll have noticed the ferrite antenna, wrapped with many turns of copper. That won't fit in a phone.
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Posted: 2005-08-27 13:22:39
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They just lazy ..i cant see why they can do it becouse they have the technollogy to do it ?what els do they want im loosing it comppletly
[ This Message was edited by: thami on 2005-08-27 17:05 ]
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Posted: 2005-08-27 17:57:14
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@mikeb
nice explanation
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Posted: 2005-08-27 17:59:51
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This thread had almost disapeared but oh no, people decide to shunt it back to the top, we have heard enough explanations as to why manufacturers have put FM not AM radios in their phones.
At least it has a radio, your phone is meant to be, guess what, a phone. For calls and text, and esato via wap
not just for an mp3 player and radio and camera and videocamera, etc. Isn't that enough for you, if you think you can do better please go and create your own phone the size and weight of a ton weight then laugh. Leave the manufacturers & technology of today to develop at its own speed not at ours.
Also please let this thread have a peaceful rest and don't shunt it back to the top by asking stupid questions
Best Regard's
Mr. Christopher Robinson
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Posted: 2005-08-27 18:05:27
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