GPS's that work through windscreens

**Jaz** · 07-23-2005, 12:28 PM

Hi,

i ordered another GPS reciever the other day, and it wont work inside the car, reception is really bad and it just wont find enough satellites.

am i going wrong somewhere with the ones i have tried?
so far ive tried these two...

http://linitx.com/product_info.php?c...roducts_id=548
and
http://www.fortuna.com.tw/u2.htm

now i know that my windscreen works with gps, as my friends bluetooth one used to work fine, as does the cabled tom tom gps for pda's. i cant work out why neither of these worked properly

anyone help me?

**grepzen** · 07-23-2005, 12:43 PM

My Holux 231 (bluetooth) works through my windscreen.. but then.. mine isn't tinted --metalic or otherwise

**Jaz** · 07-23-2005, 01:28 PM

mine shouldnt be metalic or heat reflective. and any tint on it is a standard factory tint.

signal is bad on rear window too.

**dan__wright** · 07-23-2005, 02:42 PM

if you look at the windscreen from an angle is there a blue tint to it?
i have a bu-303 with no tint and it works fine.

**Wiredwrx** · 07-23-2005, 03:24 PM

Originally Posted by Jaz

mine shouldnt be metalic or heat reflective. and any tint on it is a standard factory tint.

signal is bad on rear window too.

Factory tint can effect the signal.

This is not necessarily your receivers fault. While it may not be the most sensitive, it may not make a difference HOW sensitive it is, because of the windshield and the tint. Also realize that any type of seperation between the receiver and the signal will cause a signal degredation. Even though you can see through the winshield, that doesn't mean that the signal can make it through. Think of it this way, the GPS receiver is a an ear, and the signal is a sound wave (yes, all signals are waves, so they act in relatively the same way) While I can see through the windshield (light waves can penetrate because of thier very high frequency) sound waves may not penetrate (because of thier lower wavelength) so I may not be able to hear it. The same with your GPS receiver, the ear cannot hear the signal, even though you can see through it. Additionally, the angle of the windshield in relation to the signal source (could even be based on your location in the US) can affect the signal.

Try moving the receiver to the back shelf under the rear window (where there may not be any tint, factory or otherwise, and it has a different angle as well). See if that helps. Also, try outside the car. Unfortunately, there may not be a way to get the receiver to work inside your car. Also, another receiver probably won't make a difference, unless is it more sensitive, and from what I can see, there are only 2 common receiver ships, and they only differ by about -10db of sensitivity. While that may make the difference, it isn't a FAR superior receiver, just better.

Michael

**Jaz** · 07-23-2005, 03:54 PM

as i said, i know its not the windshield as other gps's (at least 4) have worked without a problem.

tried it on rear parcel shelf, signal is till poor on this 2nd unit, was better on the first one but still not acceptable really.

guess i will just have to keep buying them till i find one that works...

**Wiredwrx** · 07-23-2005, 06:29 PM

Originally Posted by Jaz

as i said, i know its not the windshield as other gps's (at least 4) have worked without a problem.

tried it on rear parcel shelf, signal is till poor on this 2nd unit, was better on the first one but still not acceptable really.

guess i will just have to keep buying them till i find one that works...

Then get one of the 4 that worked, and give back the ones that don't.

EDIT: Just realized, the ones that worked were not USB powerd, but powered by other means (BT has batteries, and the PDA version might be powerd internally, or by the PDA. You may have power issues powering the receivers, making them "deaf". Try them with a another computer, preferably with a different MB. It can be a laptop if you like. It is possible the low power is a result of the USB Bus on the MB you are using, or because of the PS you are using, not supplying enough power. Are you using a DC-DC, or an AC-DC? What MB are you using.

Michael

**Jaz** · 07-24-2005, 07:20 AM

good thinking.
i thought it would either work, or it wouldnt though.
i will it on a laptop in my car...

as u say tho, cant used the other types.. bluetooth isnt an option, and the pda ones dont support usb i dont think.

**Jaz** · 07-24-2005, 01:47 PM

damn. just tried it on a laptop. it worked fine.
same drivers etc.

Right... im running a P4 motherboard, a Jetway pm9ms or something, with a 2.5ghz celeron. and an opus powering it. the only things i have on the 5v rail are the cd rom drive. and then i have the touchscreen usb connector.

**ShawJohn** · 07-24-2005, 02:00 PM

I mounted my BU-303 on a small 4"x4" zinc plated (zintec) sheet (to stop interference from the cars electrics) under my sunroof (on top of the blind) and it worked great with a min of 7sats even through the glass, which has a very thin metal mesh on the inside, yet it wouldn't work under the screen with more than 4 sats. Try and mount it somewhere else... Seal it with some Sikoflex or something and whack outside of your car and it'll work miles better!