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Author Topic: What's The Noise Heard On A Speaker/Radio Before My Mobile Phone Rings ?  (Read 3796 times)

Offline neilep

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Offline graham.d

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There is a two way data communication between your phone and the cell site as part of a call set up. What you hear is the effects of the radio signal from your phone interfering with nearby electronic equipment.
 

Offline RD

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Q. What's The Noise Heard On A Speaker/Radio Before My Mobile Phone Rings ?

A. http://beta.freesound.org/people/rutgermuller/sounds/50699/

« Last Edit: 18/08/2011 13:23:55 by RD »
 

Offline neilep

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There is a two way data communication between your phone and the cell site as part of a call set up. What you hear is the effects of the radio signal from your phone interfering with nearby electronic equipment.

Thank ewe very much indeed graham !..Does this interference occur during the phone call as well ?
 

Offline neilep

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Q. What's The Noise Heard On A Speaker/Radio Before My Mobile Phone Rings ?

A. http://beta.freesound.org/people/rutgermuller/sounds/50699/



Fantastic RD....If only it were available on CD..I'd buy it !  :)
 

Offline graham.d

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There is a two way data communication between your phone and the cell site as part of a call set up. What you hear is the effects of the radio signal from your phone interfering with nearby electronic equipment.

Thank ewe very much indeed graham !..Does this interference occur during the phone call as well ?

Not usually. It is during the negotiation with the cell site that the phone gets keyed on and off at a frequency that is in the audio band and at high power. During a call the interference is not usually noticeable.
 

Offline techmind

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The interference often does persist during a call, although usually at a much quieter level as the adaptive-transmit-power turns down the transmit power of the phone during a call if you're not far from a base station.

Also you'll only get the brrrrrrpp brrrp de brrpp de brrrp brrrrp brrrp noise during "2G" GSM communications as this pulses the transmission into 217Hz bursts. If you're communicating using a funky 3G network you won't get the same interference as this newer technology doesn't pulse the transmitter in the same way.
 

Offline techmind

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One day I'll configure a snippet of a recording of the brrrrrrpp brrrp de brrpp de brrrp brrrrp brrrp sound as my SMS alert sound-effect. Geeky!
 

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