Does TTN3 Bluetooth need to be in clear site of sky?

Jammer

Can someone tell me if the Tomtom Navigator 3 Bluetooth needs to be in clear site of the sky?

I've been having a few problems.
The manual says you should have it on the dashboard or something in clear view.

Does it matter if I have it hidden away in the glove box or something?

AND can I get an extra external antenna?
Would this be on any use?

Let me know.

Thanks.

Jam
_________________
iPaq 3870
Fortuna Clip On Bluetooth
Tomtom
London
Currently testing Fortuna to see if it's any good!

MrT · Posted: Thu Aug 19, 2004 6:19 am Post subject:

The receiver needs to be able to see a good proportion of the sky, the more the better. On the dash is usually a good position as it can see roughly half of the available sky.

GPS signals can travel with only a little attenuation through many objects such as glass and plastics but not through conductive material such as metal. If you glove box is plastic and is below the windscreen without any metal above it you should get a reasonable signal. Some windscreen heat reflective coatings (Renault for one) are conductive and stop the GPS signals. Windscreen heater elements such as in Ford's have virtually no effect on the signal

I have my TT BT unit in the glove box in my car and it gets a reasonable signal. However I have added a re-radiating antenna which has a receiver outside the car (on the middle of my roof) and effectively a transmitter inside the car which is near the TT BT unit. This gives a major increase in performance as it usually picks up around 7-10 satellites as compared to 4-7 without it. Of the stronger satellite signals there is a slight increase in signal strength. This reflects the re-radiating antenna having a better view of the sky.

The advantage of a re-radiating antenna over a fixed passive antenna is that it is not connected to the TT BT unit and if you have any other GPS equipment in the car at the same time, it will also feed it.

HairlessHeart · Lifetime Member Joined: Jun 16, 2004 Posts: 11

Hi

I've managed to use my TomTom bluetooth receiver successfully when it'd been in a rucksack in the boot of my car! Admittedly, the number and strength of satellites received is slightly lower than when used in the door pocket, for example, but it still works. :D

Doug

digitalbullet · Occasional Visitor Joined: May 08, 2004 Posts: 30

my BT GPS receiver is always in my glovebox and i get about 6 satellites constantly.

Jammer · Posted: Thu Aug 19, 2004 2:34 pm Post subject:

thanks for all the replies.
but can someone alos tell me where i get an external antenna from?
thanks.
_________________
iPaq 3870
Fortuna Clip On Bluetooth
Tomtom
London
Currently testing Fortuna to see if it's any good!

dodgydodgy · Posted: Thu Aug 19, 2004 3:01 pm Post subject:

http://www.expansys.com/product.asp?code=114519

Just as an example. Check the thread here

dodgydodgy · Posted: Thu Aug 19, 2004 3:03 pm Post subject:

Or http://www.mobiledatadirect.co.uk/product_info.php?cPath=34_101&products_id=1475 as someone suggested (slightly cheaper, but check postage costs)

dlegros · Occasional Visitor Joined: Aug 03, 2004 Posts: 30

Except both of those are the propietary external antenna for TT-Go
Dom

MrT · Posted: Sat Aug 21, 2004 6:44 am Post subject:

These are both suitable. The more expensive one has the advantage that all the bits are detachable so it is easier to thread through small holes. The power of either is more than sufficient.

http://www.globalpositioningsystems.co.uk/search.php?search=re-radiating&x=17&y=10

Handnav sell the same models but I seem to remember they give them slightly different names

Mr-B · Posted: Sun Aug 22, 2004 6:30 pm Post subject:

	PocketGPS
	Web