Using a car aerial with a GPS receiver

heyitsroth · Occasional Visitor Joined: May 28, 2007 Posts: 4

Hi, I've just bought a Sony Ericsson W950i and am planning to use sat nav with it when in my car.

I don't have a stereo/Headunit in my car and I would really like to hide the GPS receiver where it used to go, so it would be perfect if there was a way of connecting my redundant car aerial to a GPS receiver (seeing as it would all be the right place and everything) in order to avoid using one of those external antennas and everything.

Is this possible? If it is do I have to look for a receiver with the appropriate connector, or do I simply buy an adapter that plugs into the common external antenna connectors whcih seem to be on most of the receivers.

Thanks in advance- Tom

p.s. any receiver I get needs to be bluetooth to work with my phone

mikealder · Posted: Mon May 28, 2007 3:09 pm Post subject:

Welcome to the forum Tom, you cannot use a car aerial to feed a GPS receiver it simply will not work, FM radio uses 88 to 108MHz the GPS system uses around the 1575MHz.

There are special aerials that can feed GSP and car radio signals from the same unit, but they are not cheap and you might have to drill a hole for it to fit, see This for such a device.

If you get a SiRF-III GPS receiver you will probably find it works even in the glovebox without an external feed - Mike

heyitsroth · Occasional Visitor Joined: May 28, 2007 Posts: 4

Thanks for the fast reply! I don't mean to dispute what you said (i've probably misread it) but is this not an appropriate adapter?

If it isn't (probably true) are there any products which allow me to replace my current aerial with one which can pick up GPS frequencies - a simple plug and play replacement with no need for drilling etc?

And one final question: is this sirf III specification like a chipset - so any sirf III receiver I buy will be basically the same thing with a different case (and different price!)? The reason I ask is I want to be sure the receiver I buy is capable of receiveing traffic information..

mikealder · Posted: Mon May 28, 2007 5:59 pm Post subject:

Lets have a look at your last question first, GPS devices will pick up signals from satellites in order to determine their position, they do not pick up RDS-TMC information UNLESS you get one specifically designed to do this duel role, do you have a device in mind?

Such devices can receive GPS information AND RDS-TMC it is the RDS-TMC side of things the addaptor you link to might be handy for, this will not supplement the GPS reception though.

Then there is the slight issue as to what software can use such a device, again what package are you thinking of loading to the new W950i not all navigation software can make use of RDS-TMC and to be honest Traffic reception in the UK via RDS is not too good to be honest (see I can understate something).

The plus point is that you can use the existing car aerial for RDS-TMC if you decide that is the route to follow, what you cannot do is use the car aerial for GPS positional information as the frequencies are too far apart for it to work correctly.

SiRF-III is a GPS receiver type, any that conform to this specification will offer very good reception even when placed in demanding conditions.

Your original post made little mention of RDS-TMC so I still stand by the original answer that a car aerial cannot be used for GPS reception, if you can let us know what nav software you are thinking of loading to the 950i we can be a little more specific in terms of an answer - Mike

heyitsroth · Occasional Visitor Joined: May 28, 2007 Posts: 4

I was thinking of tomtom 6, but I've just read up on it and I think it uses the gprs in the phone to get traffic info, rather than getting it from the receiver - sorry!

Do you think tomtom is a good choice? - my Dad used to have it in his pda before, and I thought the directions could be a bit ambiguous sometimes, and it was very glitchy with getting a gps signal, but I suppose that was just the receiver he had with it. I'm also slightly worried about the size of the screen, but I guess it'll probably be ok once i get it.

mikealder · Posted: Mon May 28, 2007 7:21 pm Post subject:

Well at least your phone is listed as compatible with TomTom 6 so thats the first hurdle over with - you know it will work.

Next you need to choose a good SiRF-III based GPS receiver, or look at the i-Blue/ Q-Starz device as a good alternative - write up Here

The only way to get traffic information with TomTom on your device is to subscribe to their service and then pay the additional GPRS usage costs, if you really think its worth while. To be honest try it for a month when you first get the software (for free, other than the GPRS cost) and work out if it is any good for your style of usage before paying for the 12 months package - Mike

heyitsroth · Occasional Visitor Joined: May 28, 2007 Posts: 4

Thanks very much for the help - I've just bought an i-blue receiver for £30 off ebay! And yes I agree with you on the traffic software with tomtom - I had thought it was free - how naeive!

One final question - which sat nav program is the best? :D A bit of an impossible question I know, but which one do you use?

Once again, thanks for all the help, and the quick replies

alix776 · Posted: Mon May 28, 2007 8:16 pm Post subject:

because you are going to a phone and not a pda/phone this does limit what is compatable with it i think your either stuck with copilot or tomotm at the moment on that hand set
_________________
currently using aponia truck navigation on windows phone. Good bye IOS don't let the door hit you on the way out .

Oh the joys of being a courier.
device Lumia 950 xl

mikealder · Posted: Mon May 28, 2007 8:22 pm Post subject:

Good luck with the receiver it should work fine for what you want. As for what software to use, you are somewhat limited by the device - not many software suppliers list that phone as compatible.

I would stick with TomTom, the other software I like to use is Route 66 but your phone is not listed as supported so steer clear of that for now. The actual software is down to what you want from the device, I don't think you will go far wrong with TT to be honest - Mike

	PocketGPS
	Web