GPS Antenna installation location

[gofishin]

With a bit of luck I will be installing my Raymarine A65 this weekend in my ally bowrider. The ‘destructions’ say to choose an antenna location;

• as low as possible
• away from other antenna or sources of interference
• away from other obstructions that block line-of-site
• etc etc

I have seen many different locations chosen; sidedecks/coamings, cabin top, rocket launchers, and quite often flush-mounted on the dash, beside other electronic equipment and under the windscreen (ally screen frames, s/s grab rails etc).

My question is how important is the location or who of you have had problems with the GPS antenna in certain locations?
Cheers
Brendon

[abundy]

Hi Brendon
I have only two weekends ago installed A65. Mounted antenna flush on side coaming. Opposite side to unit and all electronics, switch panel, etc. Used unit twice. No probs so far. In the installation book says the higher you mount the antenna you may have probs with top of the mast syndrome.
Have Navionics XL9 chart in it. The A65 is an awesome unit. Cant wait to get out this weekend just to use it. Happy days with your A65

Cheers Al

[Lapras]

Brendon,

GPS of today is a heap better than it was - the only real problems are the sky being blocked by objects, and radio transmitter interference. I'd stay away from any antenna that transmits. As for seeing the sky, typically GPS can use satellites down to about 10 degs from the horizon - the more sky it can see the better the position. Signals themselves can pass through thin non-conductive items like glass, plastic and most fibreglasses and can go around objects less than 100mm thick (assuming they are not right on top of the antenna).

Hope this helps,

Dave

[gofishin]

Thanks guys,

Al, yes it will be great when I can get out and play with my new toy. I too have the XL9 Aust. wide chart – haven’t actually seen one in action yet! Hopefully the bay will be good w’end after next so I can get out there, or outside, weather permitting.

Dave, the most appropriate location seems to be just forward of the screen(s), either side of the boat (side decks). The dilemma I have is that here I also have 27meg antenna on the port side, and was going to install a VHF antenna on the stb side. The AM/FM antenna has to go somewhere too, but should not present a problem as it receives only. Any suggestions?

cheers

[Lapras]

All I can suggest is to keep it a way from whichever radio you transmit on the most - receiving is not a problem.

In the end I doubt if you will have a problem on either side.

Dave

[PeterInSA]

gofish,
I am in the process of installing my A65 in my 16ft Half cabin. what I am wary of, is some comments in the instructions re. the Sounder Module Mounting location, eg:

"Keep away from devices that may cause interference such as motors/generators and radio transmitters/receivers." I am going to mount the unit on the transom about 700mm away from the motor. I am against mounting it in the cabin, because I am wary of possible high frequency radiation and impact on aerials/CB.

"Mount the unit at least 3ft away from a magnetic compass "(my compass, is on the roof of the cabin so on the transom no problems)

"Do not mount on the main console"

"Good ventilation is required to prevent the unit from overheating". How good is good? In my case the back seats (part of the boat) are 400mm away from the transom and there is an air cavity behind them, (linked to the front of the boat) which is where I will mount the sounder unit.

"Mount the unit where you can view the Status LED." (Yes I will be able to do this if I move the battery, lay on the floor and look up into behind the seat cavity I will see the LED.)

As a "newbie" to this technology I will avoid having anybody at the back of my boat (transducer on one side Sounder the other) while using the Finder/plotter, at least until I get use to it.

With my boat only 16 ft long, its either the front (cabin) or the back, its all down to trade-offs.

Am not knocking the instructions they are more than adequate, its just a bit of a challenge for this first timer.

Best of Luck

Peter

[gofishin]

Cheers Dave, in the end I might even ditch the 27Meg.

Peter, I haven't even read about the DSM25 Module yet, except a quick glance through some pages. Will look through before I get serious on Sunday though. Best sounder module spot for me too is at the transom, maybe ~800 from motor but is basically open for view/ventilation. Being a bowrider the console is quite low, so even at floor level the module would be within 3ft of other nav equipment etc so this area would be no good.

cheers