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I read on the hull truth that you can mount an external GPS antenna inside your cabin or console and it will work just fine....Does anyone have any experience with this method?
Is there any reason not to put two gps antenna side by side?

I asked two marine stores if it was alright to position a depth finder right next to a GPS antenna and one said it was fine and the other said about one foot of the wiring from the fishfinder should be shielded.... Does anyone know whos right?

How far from a compass should a GPS antenna be? I also read on the hull truth that one company said the should be .9 of a meter. The person in the thread said it wasn't necessary and it also isn't necessary to be three feet from a vhf antenna as is recommended..... Any thoughts????

Last but not least I may be adding a buss bar that will be about three feet from the present one and would like some input as to the guage of wire to use...I'll be using the buss bar in conjunction with a couple of terminal strips for two chartplotters, a gds black box and a vhf so I can interface everything easier....I got two different answers on this..

It's not to hard to figure out that the weather is getting nicer and its time to start working on the boat....

Thanks for any help you can give....
 

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I have installed a couple and Ive always stuck to the Manufaturers recomendations. That was outside unobstructed. My handhelds have never worked indoors. The ones that come factory in autos do not work in the garage and the ant. is mounted on the roof. That being said many manufacture them with internal ant. How does that work sittin on the dash? Who Knows? The Shadow knows....And I bet the guys that built whatever unit you are using know too. That would be my first resource for good info.
 

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Wire gauge? It depends on the amperage you're planning on drawing from it. As a general rule do not go with a size less than what is already feeding the present bus bar that is installed. However, it can be a higher gauge (thinner) wire than that if the load you're drawing a small load. For an idea on what each wire gauge is designed to draw see: American Wire Gauge table and AWG Electrical Current Load Limits

I used to have the GPS mounted next to the fish finder with no ill effect. Will it work for you? To find out temp mount everything where you want it and look for interference between devices. Don't screw any mounts in place, just lay the components where they are going to go and power them up. GPS antennas are passive devices they don't emit any energy so its doubtful they will be the source of any, if any.

On the other hand the fish finder does emit and receive energy, but the frequency at which it operates is very different from that of the GPS. Usually any transmitting device has to be carefully shielded by th manufacturer to avoid it interfering with other devices in order for it to be licensed for sale in the U.S.

My handheld GPS does not see the orbiting satellites when indoors. In the boat it works fine. Inside the cuddy it also sees and hold satellites fine.

BTW, I would agree to go with the manufacturer's recommendation. The salesman probably does not have the technical background and experience to be making these kinds of recommendations.

Lou
 

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You ask some good questions. I know the answer to one real well.

Do not put your VHF antenna withing 3 feet of your GPS antenna. It will cause you to loose your GPS signal and your GPS unit will start beeping while on the radio after several seconds. Can you tell I have had this happen?

Also the GPS antenna shoudl be outside in the open, un obstrucked.
 

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My GPS antennae is mounted under the foward slope of my flybridge and has worked great. My unit is Raymarine, I don't if other brands would work the same. Bob
 

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If you are not going to go to the trouble of running an antenna cable out to an unobstructed area then why not just go with a GPS with an internal antenna? My first choice would be an external in an unobstructed area, 3 ft away from the VHF antenna and above or below the plane of my radome. However my handheld works just fine sitting at the helm.
 

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OK, here's another option that will keep you from having to fish wires. My first boat was this way and it worked fine. Mount it on the side of the cabin/console.
 

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one of my gps ant is only 1 ft from vhf ant. the unshielded radiating element is in the very tip of vhf ant not near the base , unless you have some cheap bargain basement vhf ant thats just a bare wire the whole way up the mast you shouldnt have any problems being close together,
 
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