Are all coax GOS antennas the same?

[Alpha22]

Are all coax GPS antennas the same?

Within reason, are all coax GPS antennas pretty much the same? If the spec and voltages look the same, can I swap one for another?

I have very limited air draught due to a low bridge on a local river so do not want to mount a traditional mushroom on my GRP hard top. (mobo) Every inch counts.... we have been through with <0.25" clearance.

Could I substitute this .... http://www.ebay.co.uk/itm/ONWA-Mari...door-use-IPX6-Waterproof-HA-017-/281132853058

for something like this ?
http://www.ebay.com/itm/28dB-LNA-Ga...499469137?pt=GPS_Antennas&hash=item5d3fa0eb51

I know the plug is wrong, but that is simple to overcome.

Furthermore, as my hardtop is a GRP sandwich, would I loose much signal if I mounted it inside????

 

[PetiteFleur]

I've mounted my gps antenna on one of the vertical stanchion posts so its protected by the top rail. Used a universal bracket so it's virtually vertical. Works well and never been damaged.

 

[oldvarnish]

It seems quite common practice to mount GPS antennae under the deck. Mine works.

 

[prv]

As long as they're both powered - at the same voltage - then I think they should be interchangeable. I have used a third party antenna (looking a lot like your second example) with my Garmin 128 for the last year without any trouble.

It's under the deck, too.

Pete

 

[lw395]

The black sort in the picture are usually designed to mount magnetically on the roof of a car.
If you mount them on a flat GRP surface, it will lose some gain due to being off tune.
I used one mounted on a 9 inch circle of aluminium for a while, it was very effective.
Pretty much all of these things will work with +5V on the centre of the coax, it feeds the pre-amp which is built in to the antenna.

Mounting under the deck will work most of the time, but one day when it's really rough and there's lots of rain and spray on the deck, and you really want to know where you are, it may not work.