GPS antenna positioning.

[Mataji]

I have just replaced my chart plotter and find that the new one does not come with an internal GPS receiver. So I need to buy and fit an external antenna. I see many boats put these on the push pit. Why? That will involve drilling holes to feed the cable down to my chart table. The old plotter worked down below with its internal receiver and my tablet and phone both get good GPS signals when below so can I simply put the external antenna somewhere below close to the plotter?

 

[Glenlivet]

What plotter did you buy? Strange it has neither an internal gps OR an external one supplied as standard.

 

[RichardS]

GPS antennas/receiver are so sensitive these days that you can certainly mount it below decks. I have two, an old RS125 deck mounted and a modern one in a locker in the salon. Guess which one locks on quicker and stays locked on?

Richard

 

[Mataji]

The old plotter was a Raymarine C90W. The on/off button stopped working (together with 1 other button). Raymarine’s fixed price fix would have cost over £600 but I found a brand new E90W for £480. This is almost identical to the C90W but it has a touch screen (and, as I now find, no GPS receiver).

 

[Dougal]

I have three GPS receivers which all work extremely well bellow deck. Pretty sure this does not work with Ali or steel. Reduced functionality with ply.

 

[jwilson]

GPS antennas/receiver are so sensitive these days that you can certainly mount it below decks. I have two, an old RS125 deck mounted and a modern one in a locker in the salon. Guess which one locks on quicker and stays locked on?

Richard

I have exactly the same - original 10 year old Raymarine 125 mushroom on the pushpit slower to lock on (despite new internal battery) than a six year old Standard Horizon mushroom mounted in a hidden space behind the chart table below.

 

[Mataji]

Thanks for those replies. Looks like it might be easier than I first thought. That doesn’t often happen, especially on a boat.

 

[PaulRainbow]

Modern GPS receivers can usually be mounted below decks, as other has said. Garmin actually make under deck mounts for their N2K receivers.

 

[johnalison]

My e7 also works perfectly well below deck. The reason I believe the pushpit was commonly used, as with my old Garmin 128, is that height is not important for gaining a signal but that the additional movement at the top of the mast would confuse the system.