Externalt antenna

[gruntfuttock]

I have just orderd a GPS unit, Magellen explorer. Can any one tell me if I NEED an external antenna?
I was told at the shop it was a waste of money. Is this true?

I have a Defender

Cheers

[Bushie]

From my experience with Garmin units an external antenna in a defender is almost essential.

The GPS needs a good view of the sky to allow it to pick up the maximum satellites from all around. Satellite geometry has a big effect on accuracy. I have found that without an external aerial then you won't get good signal from any satellites behind you due to the almost vertical windsceen coupled with the roof.


Bushie

[sclarke]

Disco's you can get away with it, But Defenders nope.....

Get and external antenna, Cheap and they make a big difference.

[incisor]

external antenna is a must have IMHO

[solmanic]

With a Defender - definitely. The windscreen is too steep for the unit to pick up enough satellites from the dash. A nifty way to install an external antenna on a Defender permanently is to house it within your air snorkel (assuming you have one). The antenna is safe from weather and theiving hands and you can run the cable into the engine bay through the air pipe and then pop it out and through the firewall to the dash. The plastic snorkel then also means the antenna has a good, unobstructed view of the sky.

Incidentally, a friend of mine who is involved in manufacturing a GPS car minder system suggested that the entire aluminium roof of a Landrover should make a good antenna if you could wire it up correctly. Don't know whether this is likely, but shouldn't be too hard to test out.

[gruntfuttock]

Thanks,
I did try without but it could only get a fix on one or at the best two satilites. As everyone said it is a definte must have.

Thaks for the input style_emoticons/<#EMO_DIR#>/biggrin.gif

[gruntfuttock]

Tried today the same exercise. Found and had a fix on at least 6 satelites. The best I had was 13 without an antenna. I still have ordered an external antenna though.

[rmp]

The answer is "it depends". Specifically, the answer is a combination of:

- receiver antenna performance
- where you mount it in the vehicle
- where you drive it

If you spend lot of time in the High Country (hills, trees etc) an antenna is a good idea. If you're an outback tourist you probably won't need one.

Try without and if you find you need it, get it.