gps antenna- mix and match brands??

[adamdavi3s]

Hi,

I have just upgraded my Furuno GPS to a Garmin GPSMAP, I was hoping to use the same antenna (a Furuno one) as it is mounted nicely on my A-Frame.

The Furuno GPS unit worked fine and got satelites usually within seconds.

The GPS map I could not get to pick up a signal, so I tried just holding the Garmin antenna which then got a signal perfectly.

When I plugged it back into the Furuno one, it kept moaning that the antenna length had been shortened??

The Furuno is on about 5m of coaxial which runs under the deck to the antenna, which has an additional whip on the top of it. The garmin is on about 2 feet of coax and just being held by me!!

Any ideas?

I'd like to use the Furuno one if possible, but if not I guess I can remove it and create a join in the coax to mount the garmin one (as I will need the length running under the deck) but then I am not sure how badly this will degrade the signal, or even if the coax is the problem?

[al40]

very unlikely you can interchange antenna like that... Some of the GPS units have active antenna (ie amps built into the antenna), some of them are more than antenna and are actually a GPS receiver that transmits lat/long over NMEA to the receiver (eg some Lowrance units).

Even if the Antenna did work, the designers will impedence match the antenna to the instrument so for best performance use the correct antenna with the supplied cable.

It sounds like you have an exposed coax end at present - does this not mean it's easy to just pull a new cable through the A-Frame? I know it's extra effort but will result in a better result (or working result)!

[adamdavi3s]

AHh ok makes sense!

I can mount the garmin up easily enough but haven't actually checked what connection is on the bottom of the antenna. As there is only about 2 feet of cable, I either need to hook up a whole length (I may as well use the cable in place in that case?!) Or just join it at the back end?? If that makes sense!

Many thanks for the information though :-)

[JABS]

I put the new antenna on the front of the console. It looks cool and works perfectly. Also avoids the grief of running cables through a duct and into the A Frame.

[jwalker]

A GPS antenna doesn't need to be high,
it just needs to see the sky.
Would I lie? Give it a try.

[adamdavi3s]

How very poetic!!

I have put the garmin on the a-frame mount and just used a coax coupler covered in self- amalgamating which seems to have done the trick!!

Now just the metz antenna to do