I'm trying to do a bit of a stealth install of my AVIC F90bt. My car has a little compartment in the middle of the dash area which I was planning to hide the GPS antenna in. This would be equivilent to sticking the GPS in the middle of your dash right below the front windshield in most other cars, except there is a little bit of plastic in the way.

Unfortunately the metal pad that comes with the GPS antenna and the instructions say "must be used" and "can't be cut" sort of foils my whole plan of creating a little bracket and mounting the GPS antenna to the top of the compartment in order to allow the compartment to be fully useable afterwards. If I placed the metal pad down then attached the GPS I'd be placing items on top of the antenna which I'm certian would cause nav problems.

So my question really is what is the deal with the metal sheet? Does anyone know what it actually does other than providing a metal surface to stick to? Does it some how increase the surface area of the antenna allowing for more satellites to be tracked? Does it really have to be used?

i ran mine for about 3 days without because i didnt read the install manual, and it worked ok. i put the plate in anyway because it was easy and didnt effect the look because i have it mounted discreetly.

I think the most important part is to have it stuck to something metal. It is magnetic after all so they intended it that way

And more metal = larger antenna = better reception. In theory at least

i have mine stealthy tiewraped to my rear view mirror and its 100% dont worry about putting it on metal..

I put mine on the little metal plate and hid it under the plastic dash cover directly underneath my windshield. It works like a charm.

I put mine on the little metal plate and hid it under the plastic dash cover directly underneath my windshield. It works like a charm.

i just stick em to the top of the unit

done 100-200 like that and have had maybe 3 not get perfect reception (because there was metal in the dash, like vent systems, blowers, something dumb like that)

and you dont have to see it

Plastic is invisible to radio waves unless its painted with a paint that has metal in it. In that case it may be partially invisible then, but it depends on how much metal is in the paint. I have mine under an aluminum vent grille on the dash of my Jetta. It works but the grille reduces the signal strength so I'm looking for a plastic replacement now.

Charlie

If by chance you are talking about the compartment in the hhr, I put my antenna in there and it works perfectly. If it isn't the hhr, I still don't see why it wouldn't work since the one in my hhr works just fine.

I used the little magnetic sheet under my satellite antenna instead (installed on the rear shelf) and it dramatically improved the reception. The GPS antenna seemed to get signal no matter what (unless it was covered). Seems a lot less susceptible to signal loss.