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by Buttons840 892 days ago
It also works holding it near your torso, don't have to use your head.

Although, the joke you tell your friends is that it only works if they open their mouth and stick out their tongue like a satellite dish.

The fact that it works next to your torso made me think it was just a matter of bouncing half the radio emissions towards the vehicle, thus doubling the signal. Just like someone holding an omni-directional campaign lamp close to their body increases the light headed in a certain directions.

4 comments

That was my first thought too, but the OPs tests had the range only improving when held to the head.
I've had my fob fail to work multiple times while walking away from my car, so I take it out of my pocket and put it near my lower back and it works (even though I'm now even farther away because I'm walking).
That's slightly different though, sounds like fob went from being blocked by your body to no longer being blocked by your body.
i suspect the torso's cavity isn't as amplifying as the liquid in your brain.

an interesting test would be to try a full bladder vs empty bladder...

We could then measure how the signal range changes as you pee, particularly with the length of the urine stream.

I'm serious. This would be an analogue to those navy experiments with shooting streams of sea water to fashion temporary antennas of arbitrary length, instead of having permanent ones that have fixed length and stick out.

Thanks for the liquid antenna pointer, I had no idea this was actually tried! Apparently not only the navy thought about this, but there are idea floating around about using liquid metal for variable length antennas.

One of the links I found: https://www.mwrf.com/technologies/embedded/systems/article/2...

It’s just using the water in your body as an antenna.

You can see the same effect by holding the car remote to a water bottle.

You’ll notice the water bottle gives you about the same extended range as your head.

> You can see the same effect by holding the car remote to a water bottle.

And this ^ doesn't actually work.

I know it because I specifically tested it. Went from 2L bottles and all the way to 8L jug. Nada. But the head works.

You’ve piqued my curiosity.

I will have to run more tests.

clean water isn't a great conductor - the body is a bag of dirty water...
I’ve always put the key behind my head when doing this, and can confirm, it extends the range through experimentation.

I thought for sure I’d be absorbing it with my head but I definitely get extra range.

vs holding it out at arms length but same height? Ground interference is a thing.
I can confirm that holding the remote next to the head doesn't work, but touching chin, temple or the back of the head does extend the range. This works not just with car remotes, but also with garage door openers.
My favorite place (and yes I do this since I saw the Top Gear) is under the chin, pointing the fob/key upwards and opening my mouth. So it doesn't use the skull's cavity but the mouth's (or so I think/believe)
Have you tried standing on one leg, and touching your nose with the free hand. Vast improvement over the amatuer technique
Yes, holding at same height. I did not know about ground interference! Thanks.
> Although, the joke you tell your friends is that it only works if they open their mouth and stick out their tongue like a satellite dish.

I cannot wait to trick someone into doing this