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Figured I would throw this out there for all you alarm guys.
My mother was over this weekend and she had a story as usual. She had a friend who's husband was out golfing. Somehow he locked his keys in the trunk of the car. Called his wife to bring the extra set of keys to open the car. Being a smart ass he said just hold the transmitter up to the phone and unlock the car for me. She swears up and down that this worked. Anyone care to discuss or even attempt?
 

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It could happen... depends on the distance she was from the golf course and the range of the remote.

Either that or he had a smartphone enabled remote starter :)
 

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Mythbusters debunked this. However I tried it from opposite sides of my house once and it worked. Go figure...
 

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Opposite sides of your house with your car in the driveway? Of course it's going to work. Most systems have about a 1/4 mile range. Obviously obstructions, frequency, etc. come into play.

I call BS. This isn't the first time I've heard this myth, but it's just that a myth.

If you think about how the remote transmitter works and how cell phones work, or even land lines, you'll know logically it can't.
 

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Opposite sides of your house with your car in the driveway? Of course it's going to work. Most systems have about a 1/4 mile range. Obviously obstructions, frequency, etc. come into play.

I call BS. This isn't the first time I've heard this myth, but it's just that a myth.

If you think about how the remote transmitter works and how cell phones work, or even land lines, you'll know logically it can't.
I have never seen a stock remote that works at 100 yds much less a 1/4 mile!!!

When I did it, it worked with the phone but not without it. Explain that...
 

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might have used your phone as an antenna. try holding your remote up to your head. you get a greater distance out of it. and maybe brain cancer. Of which I don't have to worry about. :)
 

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might have used your phone as an antenna. try holding your remote up to your head. you get a greater distance out of it. and maybe brain cancer. Of which I don't have to worry about. :)
Yeah I've done the mouth trick often. My mouth tends to amplify everything that goes through my head anyways! :)
 

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Good ol 'chin trick'.. works every time! ;)
Turns your body into a end-fed radiator with a ground stub whereas holding it makes your body a dipole.

The body is actually the antenna in this situation. Sometime back up a decent distance and see how far it work when you sit the remote on the ground and poke it with a yardstick... No body coupling, ****ty antenna. By altering the place on the body where the transmitter couples you change the pattern of said radiating antenna. The chin makes the pattern a bigass doughnut shape due tot he ground stub whereas the dipole effect by holding your arm out may have less gain in horizontal plane but has more of an omnidirectional pattern.

The phone trick. The ONLY way this would work is IF the phone is running at or close to the same frequency, or a multiple of 2, as the transmitter and by holding the one up far away you somehow couple the transmitter with the multiplexor section of the phone transmitter by sheer luck.

This is assuming that the IF section of the phone receiver is loose enough to let that signal pass.

That sounds possible, but it's not, because phones are not point to point devices and the audio you hear is not actually the person's voice. it's a series of vocoders that reproduce the person's voice from data extrapolated from the phones digital signal. In other words, in no way, on a current cell phone that is still in use (I do believe they have nixed analog right) is the audio/RF output of the remote phone even close to being that of the receiving phone, in fact one phone may be transmitting on one band (like Verizon) whereas the other will be receiving on a GSM band) the RF trick will not work.... debunked via common sense.

It would be fun to try with loose consumer level radios, but since FRS runs at 465 meg (or close,) and Key FOBS run at 315 meg... then it's pretty much impossible to get pass the IF filter or into the multiplexor section without enormous amounts of loss.
 

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what about a cordless phone. not practical though I guess.
 
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