Automobile passive cell phone antennas, do they work?

[scottmandue]

I see these antennas you can you can stick to the window of your car and supposedly they increase the signal to your cell phone inside the car.

My inner BS detector says they probably don't work.

However if I put my cellphone on the center console and use the bluetooth some times I have to pick up the phone and hold it up higher to get a better signal thus negating the "hands free" advantage of using bluetooth in the first place.

I see many of these antennas on cars around town but then I see lots of useless crap tacked onto cars around town.

Anyone use one of these things? Do they really work? It would be worth the $10-$20 if it did.

TIA

[island911]

They can help, a tiny bit ...sometimes. --kind of like when you have poor tv reception, unless you lift your right arm and left leg. Problem for the cellphone, is that you don't get quick signal-strength feed-back to know where the sweet spot is.

many handsets have an external antenna jack, which allows clicking into an coaxed external antenna. --that will do the most for ya.

[Schumi]

I'm guessing it's made up of a strip or two strips of metal together that are designed to resonate at the same frequency as the cell signals. This makes them act as tiny amplifiers between your phone and the towers. Just a guess though.

[9dreizig]

Try an aluminum foil hat while you talk on your cell, that should work even better!! LOL

[island911]

Schumi has it pretty well. The ones I've seen around have a full wave length topside, and a 1/4 or 1/8th wave antenna on the window side. (pretty much what your handset has.) And to make things worse (and sometimes better,) they have directionality about them.

http://en.wikipedia.org/wiki/Passive_repeater

I would skip it.

[scottmandue]

But more importantly... do chicks dig them? Yo!

[m21sniper]

If i had one they would.

LOL...

[Normy]

I'm calling BS on this one.

-The PO of my car [henceforth to be referred to by the moniker "butteater"] installed a passive repeater antenna on the roof of my '85 928. I've kept the thing because it is pretty innocuous, but I don't think it does anything. I never use my phone in my car, and if someone calls me I pull over, but when I am riding in someone else's car or in a hotel van I've not noticed any advantage because of this little antenna. I have a Motorola RAZR V3 phone.

N

PS: In the pic, the antenna is in the upper right hand corner.

[Schumi]

Normy... I love black 928's. Got any more pics for us? ?

[tcar]

Originally Posted by Normy

I never use my phone in my car, and if someone calls me I pull over

So do you get out, or are you 'using the phone in the car'?

Shouldn't make any difference whether you're driving or not.