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What's the best GPS antenna mounting location for my situation?
tlukasavige172
So I have a Ford F250 and I'm looking at mounting locations for the GPS antenna. I carry a truck bed camper so the bed overhangs the entire roof of my truck. I'm looking for something that is highly reliable and accurate. So, I've gotten as far as the BR-350 permanent mount and BU-353 magnetic. I like the BR-350 because it has 15' of cord. My laptop is mounted in the middle of my truck and I'd like to tuck the cord away and bring it through the firewall. That said, do they make extensions for the USB cords? I was thinking of drilling a hole right in the middle of my hood and mounting the antenna there. Do you think this would be a good location (since the roof is covered)? How about the length of the cord, will it take away from the accuracy or strength of the signal? I also have a cb antenna on the edge of my hood, will it affect the GPS at all or vise versa? Thanks in advance for all the knowledge.
tcassidy
In the olden days, it was important to have the GPS antenna in a location that was open to the sky in all directions. GPS devices are much more sensitive now and a dash mount will usually suffice, even with the camper overhang. Of course a mount outside such as the BR350 is great but may not be necessary. The BU-353 is waterproof and magnetic so could be mounted outside but the cord is pretty short. A reasonable quaility/ length USB extension should work fine.

Your CB antenna location should not affect the GPS performance. I suppose it could overpower the GPS antenna while you were transmitting if you put them side by side though.

Terry
tlukasavige172
Thanks for the info. What do you look for in USB extensions? What kind of wire should it be made of? Would there be any adverse effects of having 15 feet of cable instead of the 5 they provide? Thanks.
tcassidy
I think USB is rated for at least that length. The only signal on the cord is digital (the GPS converts the satellite signal into simple low speed digital data) and the 5 volts to run the GPS. Look for a reasonable quality extension to ensure good shielding. I have a 10 foot one that cost about $25 CAN several years ago but have never tried it for that purpose.

If the BU-353 will reach the dash, why don't you try it there before doing all that wiring?

Terry
malaki86
You can also get what's called an active extension cable. It's a powered cable that receives power from the USB port for longer lengths. I ran a 25' active extension cable in my truck to a 4-port hub in the front, which I had my touchscreen display, keyboard/touchpad & USB receiver hooked to.

As for the mounting of the antenna, I had mine on a metal plate mounted within inches of the CB antenna. It never caused a problem.
Ken in Regina
I'm with Terry. With the BU-353 magnetic mount you can mount it out on the hood (with an extension) if you really need to, and there might be some occasional situations when that is necessary, like deep mountain canyons or deep city canyons. But I think you'll find that most of the time it will work just fine on the dash out as close to the windshield as you can get it.

With an extension, keep in mind that you can't use a long one anyway. You can't have the connector outside in the weather, so the cord on the BU-353 will have to come inside the cab far enough for the connector to be just inside. Probably in through the front of the passenger door. The weather strip in the door is soft and flexible enough that it won't hurt the cable. Then you just need a long enough extension to reach the laptop. 10 ft. will likely be way overkill.

Also keep in mind that the wavelength of GPS signals is way shorter than CB so you only need a tiny ground plane. About 4" or 5". So you don't need to place the antenna in the centre of the hood. If you run it out the front of the passenger door you are better off to place it on the right front fender so you can get it as far forward from the camper overhang as possible. That will buy you more than having it centred.

...ken...
Mandolin Guy
I used to have a Class C motorhome with the overhang over the cab. Both the PC-connected antenna (for S&T & DeLorme) and the vehicle unit worked great while sitting on the dash. I'm sure there was some degradation in the amount of data received but it wasn't noticeable. I never had a problem.
tlukasavige172
Awesome. Thanks for all the advice guys. I'll buy the BU-353 and do some playing around with it to see where the best spot for it would be. Thanks again.
kft
If you have rooftop ac the enclosure is the perfect place for a thru mount antenna, and of course its the highest place on the rv.

We did this on our B+; to get to the interior I also drilled a small hole in the plenum, its plastic also and used duct putty to seal. From here it was a simple matter to drop the coax down, too easy really.

Performance is perfect.

This weekend I am mounting a thru mount antenna for the Smooth Talker booster, if you wish I take pics of the gps antenna mount.
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