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Cannot believe anyone would think it could work. Sending a radio signal (or for older cars infrared) via a voice channel on a mobile... The wind-up is someone even asking on here??
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I feel a bit of a muppet for saying this, but when this did the rounds at work last year we tried it, and managed to unlock my car from an office block a good 10 minutes walk from the car park. I wonder if we were close enough that the mobile amplified the signal from the key rather than transmitted it......
May try it again now :-)
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Cannot believe anyone would think it could work. Sending a radio signal (or for older cars infrared) via a voice channel on a mobile... >>
I take no responsibility for being the author of the original email. I get the impression it was American in origin so that probably speaks volumes in itself.
The wind-up is someone even askingon here??
Don't panic, I had my doubts as to the authenticity but hey, years ago they all thought the Sun went round the Earth until someone proved them wrong so someone had to try it to disprove the theory. Anyway if some keyfobs emit radio waves, isn't it at lease partly believable that a phone emitting radio waves, or radio frequency electromagnetic fields could affect a locking mechanism using the same technology?
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Anyway if some keyfobs emit radio waves isn't it at lease partly believable that a phone emitting radio waves or radio frequency electromagnetic fields could affect a locking mechanism using the same technology?
Only if the wormhole generator is connected to the flux capacitor.
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Didn't MINI offer a starting/unlocking gadget which had something to do with a mobile?
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I seem to remember Jeremy Clarkson proving that pressing a key remote control to your head amplified the signal enough to unlock a vehicle some distance away.
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Yes, there is a fair chance that one's head will reflect the signal in such a way that it will boost the signal level received by the car and hence open it, although it certainly won't work 100% of the time.
For that matter there is a remote (ha ha) chance that the RF signal from a mobile phone will interfere with a car's electronics in such a way that the car will unlock.
But there's no way you can send the signal from a blipper over a phone network .
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"Only if the wormhole generator is connected to the flux capacitor"
and even then it would require a reverse flow co-axial warp phase generator surely?
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>>I take no responsibility for being the author of the original email
Still asked here though ;-)
If this worked, then on similar principles (which we know do not work) you could get your wireless broadband by using free minutes to call home to "listen" to your wifi network. That's nonsense but so is the opening of cars.
Edited by rtj70 on 04/03/2009 at 22:38
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Does it has to be a spouse or can a friend/cleaner/gardener be able to do it ?
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Of course the Sun goes round the Earth...it goes over the western horizon and in the morning it comes up behind you in the east. If that's not going round, I don't know what is !
Ted
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It won't work at all. I don't know all the technical details anymore [I once would have done, spent too much time studying radio frequencies and mobile phone technologies etc].
Some of these mythes are true though, such as the remove fob pointing to your brain thing, you can extend the distance by at least 20 times by doing this as your body acts as an anthena.
Btw does anybody know what frequencies remote key fobs use? I have very limited experience of them but it should be possible to build an electronic black box quite easily which will open a lot of cars but I guess modern remote fob codes are all encrpyted etc to make this sort of thing harder.
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Btw does anybody know what frequencies remote key fobs use?
Toyota keys use 433Mhz, not sure its the same for every brand.
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I heard Chris Evans on Radio 2 tonight (Wed) mention about using mobiles and transmitting signals - I couldn't believe that he was mentioning this on national radio - but could imagine lots of people going out and tying to do so there and then - muppets.
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Looking at the GSM specifications (I know most phones are now 3g, but all phones are GSM) it seems they do transmit in the same range as a car fob, so it may well be possible to write a peice of software which can send the data signal to a car and open it. However you could do with this by building your own circuit anyway.
My guess is that car fobs use quite fancy encryption and it is not just a simple 64 byte code.
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When remote radio fobs first came out the signal could be captured and replayed to gain access to a car. Then they changed them to use rolling codes which means the code needed to unlock the car is different each time.
GSM is a 900MHz or 1800MHz signal. It would not be in the same range as mobile phones or phones would interfere with it. The radio spectrum is closely controlled and profitably sold - look what they did in the UK for 3G. Soon some of the GSM 900MHz frequency will be up for sale for use for 3G too.
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Looking at the GSM specifications (I know most phones are now 3g but all phones are GSM) it seems they do transmit in the same range as a car fob
Transmission frequencies for car based remote keyless entry systems = 315MHz/ 433MHz.
Transmission frequencies for GSM mobile phones = 900MHz/ 1800MHz (world except USA) and 850MHz/ 1900MHz (USA).
Only exceptions I know of are GSM systems for military use which use 380 and 410MHz and some really old systems in Finland and Sweden, pioneered by Nokia and Ericsson in the mid eighties, which use 450 and 480MHz.
UMTS (3G) presently uses 1900MHz and 2100MHz (AFAIK).
I'll get my coat.
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That will treat me not to trust Wiki, though it was probably the Swedish spec it was refering to it, I thought at the time it seemed a little low but it was nearly 2:00am and I was not thinking properly.
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Looking at the GSM specifications (I know most phones are now 3g but all phones are GSM) it seems they do transmit in the same range as a car fob so it may well be possible to write a peice of software which can send
No they don't, speaking as someone as someone with 15 years plus phone network design experience! As already pointed out, keyfobs use 433 MHz, GSM tansmit in the UK uses 935 - 960 MHz and 1805 - 1880 MHz, UMTS FDD band 1 ( 3G) uses 2112 - 2167 MHz - off the top of my head. The only close transmit band is GSM450 and its variants, which are used pretty much nowhere in Western Europe.
As I already said earlier in the thread there is a remote chance the TX pulse from the phone could interfere with the car's electronics in such a manner that the car would unlock, but it certainly isn't likely.
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I apologise for that, I got my info from wikipedia wrong. I can't remember exactly how it works but when you trasnmit a radio signal you get extra undwanted signals don't you, e.g a singal at 935mhz would also have unwanted flares outside that range, I cannot remember the name for it now :( Sidebands?
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Yes, you are correct that some level of out of band transmission is allowed, indeed pretty much inevitable, I can't remember the phone spec. off the top of my head, but the base station could transmit -30 dBm at 433 MHz.
LOL, I've just realised I posted the base station transmit frequencies in my previous message, rather than the phone ones, so I'm off to flush my head down the loo now.
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>>..but could imagine lots of people going out and tying to do so there and then - muppets. >>
What! That would mean missing the Chris Evans programme....:-)
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