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zippy656
17-12-2010, 08:15
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We might not all be aware but sending an SMS requires less signal than making a voice call.

The new service from emergencysms.org.uk (http://www.emergencysms.org.uk/) lets registered users send an SMS to 999 in case of emergency rather than having to call.

clivvy
17-12-2010, 08:37
weird, so how does it locate you then? can only fit so much in a text, and it takes more time and more concentration to text than speak...still, its there isnt it!

lacroupade
17-12-2010, 12:17
weird, so how does it locate you then? can only fit so much in a text, and it takes more time and more concentration to text than speak...still, its there isnt it!

Agree...was involved in mobile from the very earliest technology when you had a handset attached to a thing the size of a car battery, and the fact is your phone either has a signal or it doesn't - so it either works or it doesn't. Might be confused with the tiny amount of bandwidth that a text uses, which is why 10p is/was soooooo expensive......relatively its like charging £40-50 a minute for a voice call, hugely profitable.

It may be that, if the phone is tipping in and out of signal, then it has time to send a text (with its tiny amount of data) even though it can't lock on long enough to make a voice call (with its larger amount of data). But it doesn't handle more or less data depending on where you are in a cell, its just the length of time you can hang on to a signal for something to happen thats the issue. :)

rayf3262
17-12-2010, 12:26
When making a voice call the phone and the cell to which is attached to are required to negotiate a delay variable, this is to reduce the effects of echo etc.
This timing is based on distance between the two and has a finite range (it's actually only 8 bits) which results in a theoretical maximum range for an audio call to be established. I think it's in the region of some 20 odd miles.

An SMS has no such requirements, and ball park location can be achieved by identifying the cell that handled the SMS.

Thomas-the-Terrano2
18-12-2010, 10:49
is this like the setup where cars involved in crashes can contact emergency
services themselves, think based on car's brain detecting sudden braking
and air bags firing. forget which brand is offering it, gm? in states, sort of
thing would expect volvo to be in on?

does this sms thing overide normal networks too like 112 can to get the
message out what ever way it can?