Locked the keys in the car

[bruce]

Some body forwarded me this; but was unsure if this really would work, has anyone tried it?
read below.....
**************************************
Locked the keys in the car? Your car has remote keys?

This may come in handy someday. Good reason to own a cell phone: If you
lock your keys in the car and the spare keys are home, call someone on your
cell phone. Hold your cell phone about a foot from your car door and have
the other person at your home press the unlock
button, holding it near the phone on their end. Your car will unlock. Saves
someone from having to drive your keys to you. Distance is no object. You
could be hundreds of miles away, and if you can reach someone
who has the other "remote" for your car,you can unlock the doors (or the
trunk).Editor's Note: *It works fine! We tried it out and it unlocked
our car over a cell phone!"

Regards
Bruce

[?ushk@r]

Cell phone!! Unlock!! Did u try that Bruce?

[Abhay]

http://www.breakthechain.org/exclusives/phonelocks.html

http://www.snopes.com/autos/techno/keyless.asp

This is total nonsense

[Conan]

It might work if the signals are sound waves, not sure but.

[viper]

Hey Bruce,

Only a part of the article or ad was forwarded to you. This was part of an article on a vehicle security system cant recollect the name though.

Viper

[Rishi]

How can u lock the car if the remote is in the car??

i am assuming that the remote is part of the key chain!

[shuvc]

I faintly recall this being discussed in some thread earlier

[airfoil]

I've tried this and it works!

A little bit of trial & error is involved - it worked for me when I put the cell phone on speaker. I use the Autocop system.

[viper]

Hey Bruce,

Check out Irwin's post on page 3 under Technical Stuff under the heading Car Security System. The product is called Microvbb.

Viper

[Boom Shiva]

Originally Posted by Rishi

How can u lock the car if the remote is in the car??

i am assuming that the remote is part of the key chain!

I think you have a point!

[RX135]

Does it work on sound waves?

[Samurai]

Ok, let me add my piece. I have extensive experience designing/developing telephony software, also I graduated as E&C engineer.

Here is one reason why this can't work.

When sound energy hits the mic in the cellphone, the membrane vibrates and converts the sound energy into electrical pulse/energy. Now, the human voice falls within 2KHz-4KHz frequency. Therefore, in order to reproduce it faithfully we only need to sample it at twice the highest frequency(Nyquist frequency). That means the voice is sampled at 8KHz or 8192 times every second. This process is called A2D or analog to digital conversion. After this your voice is just a stream of zeros and ones which gets transmitted to the destination. On the other side the process is reversed (D2A conversion and then to speaker membrane) to reproduce the sound.

As you see, if the frequency in question is greater than 4KHz, the chances of that passing to the other side is mathematically impossible. And I believe the remote locking frequency is definitely outside the audible frequency.

[filcord]

Originally Posted by Rishi

How can u lock the car if the remote is in the car??

i am assuming that the remote is part of the key chain!

I have the Maruti Nipppon system. This can be programmed so that the car doors automatically lock 30 sec after the ignition is turned off and the last door closes. You could theoretically have the key in the car in such a case.

I was warned by the dealer to be careful I have the key with me, so I have disarmed this feature, precisely to avoid being locked out.

[RX135]

Originally Posted by Samurai

As you see, if the frequency in question is greater than 4KHz, the chances of that passing to the other side is mathematically impossible. And I believe the remote locking frequency is definitely outside the audible frequency.

Didn't get this last part which you said is impossible. If let's say, the frequency is 5KHz, can't we sample at 10KHz and pass it on?

[Xsailor]

Originally Posted by filcord

I have the Maruti Nipppon system. This can be programmed so that the car doors automatically lock 30 sec after the ignition is turned off and the last door closes. You could theoretically have the key in the car in such a case.

I was warned by the dealer to be careful I have the key with me, so I have disarmed this feature, precisely to avoid being locked out.

Ditto that, filcord.

Useless feature that. I got it "cancelled" on the Nippon of my Santro.

Cheers