Safe Speed Forums

Think it depends on the network, i've certainly rcieved the message "the phone you are calling is switched off" before now.

Modern phones communicate with the cell when you turn them off. I presume that they say 'bye bye, I'm going off now'.

You can check what your phone does by holding it near a detuned am radio and listening to the bleeps and bloops.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Presumably though, this only applies if you switch them off gracefully via the power button/powerdown menu option/etc, as opposed to simply yanking out the battery... Indeed, on my MDA Pro (and most/all Windows Mobile-based phones), removing the battery is the only way to switch them off completely.

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Chris

Yup, the only way (on O2 at least) for the caller to receive the message that the call cannot be connected is to remove the battery.
If you switch the handset off properly, then the caller receives the message that the phone is switched off.

Well, I've been building antennas for a few decades now, there are many wonderful and varied designs. I find it quite funny that people think that any beam antenna only receives from one direction (and so transmits as well). It is better to say that it "concentrates" the signal from/to the direction it is pointing. Some have quite good gain....in the order of 15 db...or a bit more, but the sidelobes on the "domestic" type can be only 3-5db down on the main lobe, and the front-to-back ratio can be as good as 30db different, or as bad as only a few db. If you want a decent front-to-back and a good gain then you really need a parabolic dish. The problem with aiming a high gain antenna at a cell base is not finding it (they ain't hidden much) but of throwing a thousand watts of power at a close cell base, and also at any others in the beam path....and you also have the problem of reflection from obstacles in the path....and the cell system can still approximate your distance from one base because of the continual handshaking from the system.
As for turning the thing off....not so good if you want to be not found. The majority of mobiles don't actually go off...just a form of standby...some can even be commanded on by the system...

As for the "bug-phone"....I've seen the software around...mobango or some such site.....and also seen the version that enables your phone to be used as a remote video surveillance system !!!

http://www.youtube.com/watch?v=ujosfSkHFrQ

http://www.news.com/2100-1029_3-6140191.html

That is if call diversion is not used. If it is , then the phone will switch straight to Voicemail, as it would if you were on the phone. ( least thats on our work O2 network)

That idea of Paul's with AM radio works well with cordless phones too .

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

The thing to do is NOT have a mobile phone.

I haven't got one - and I wouldn't have one even if you paid me much fine gold.

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Save a cow - eat a vegetarian

Yup!..... Done this too Twister! (in the absence of a tin or bacco foil of course)..............