Can an existing roof mount antenna be used as a GPS for laptop?
First post... what I'd like to do is utilize several roof mounts I have left over on my truck from when my dad had the truck. They're NMO/Motorola-style mounts... is there a way I can interface a coaxial antenna (using mini-coax) into my laptop so I can use a PC-Based GPS program? I'm using S&T's... does anybody make a USB adapter or PCI card that would allow me to plug in a coaxial antenna cable and use it as a GPS antenna? Thanks in advance,

Ken in Regina
Hi JonN,

Welcome to the forum.

I apologize if I have misunderstood your question. To use a navigation program like Streets&Trips on your laptop, you can't just use an antenna, like for FM or CB. You must use a GPS receiver.

A GPS receiver for a laptop -- like, say, the Globalsat BU-353 - includes an antenna and an electronic signal processing module that receives the GPS signals from the GPS satellites, decodes those signals, does the calculations to figure out your position and delivers the decoded digital position data to the laptop computer.

Right, I'm aware of that. In the commercial antenna catalogs, there are GPS antenna that mount on the roof of the vehicle. However, most of the antennas are coaxial... what I want to know is if there is an interface that would use a GPS antenna on the roof of my truck with my laptop? I would think there would be a PC card that would contain all the electronics and processing components and would also have a coaxial input. Is there such a thing? Is there any way I could work something like that?

BTW, thanks for the welcome! I didn't expect a reply so fast...
Marvin Hlavac
Hi Jon. Look for a USB or Bluetooth GPS receiver that has a connector for an external antenna. Holux GPSlim 236 comes to mind, but there may be others.

The Holux GPSlim 236 does have an internal antenna, but it also allows you to connect an external antenna, if you so desire. The antenna would have to work on the specific frequency.
Ken in Regina
Well, you never know when someone may be hanging around on these forums.

I wanted to make sure you understood what you were asking for because most people don't know, and don't need to know, the difference between a GPS antenna and a GPS receiver.

The most common connectors on GPS antennas are MCX because most use really thin coax for the cable. But you can get them with BNC and a variety of other connectors from antenna suppliers like Gilsson. And you can get adapters for things like BNC -> MCX and vice versa.

Many of the personal navigation devices like Garmin's Nuvi models and some other handheld models have MCX connectors to allow connection of an external antenna to enhance their ability to receive signals in difficult conditions. But these are complete self-contained navigation devices. I don't know of any similar arrangements for the receiver components for a laptop.

All of the devices I am aware of for use with PCs are combined receiver/antenna units. That doesn't mean there aren't any that can accept an external antenna connection. It just means I haven't looked really hard because the USB and Bluetooth receivers that are available have been satisfactory for me in all respects.

For instance, if you want something you can mount on the roof, receivers like the Globalsat BU-353 are contained in weatherproof housings and have a magnetic base for attachment on the outside of a vehicle. They are identical in size to the typical active antennas you would get from a company like Gilsson or Wi-Sys. They connect directly to a USB port and work nicely with all of the navigation programs I've tried on my netbook and laptop ... that's all the programs you see listed on Laptop GPS World's home page and at least a couple or three that aren't.

My BU-353, when mounted on the roof and connected to my netbook, has the same receive performance as, say, my Wi-Sys external antenna when it's connected to my Nuvi 765T.

Ken in Regina
If your circumstances require you to use a laptop for navigation rather than a personal navigation device that will accept an external antenna (or you just prefer it) AND you really need to be able to connect the signal from an external GPS antenna rather than sticking a combined receiver/antenna unit on the outside of the vehicle, there is one more possible solution: a reradiating antenna. Here's one example:

GPS Central (Canada), Re-Radiating Antenna

Ken in Regina

Here is a receiver you might be interested in: Holux GPSlim 236.

It's a Bluetooth receiver that accepts an external antenna. The following post describes a personal experience with it.


laptopgpsworld.com About