Fitting GPS...... Help

Jieboy · 10 December 2005, 17:13

I have been fitting my new Garmin 128 GPS today, everything was going ok until i got to the aerial. I am going to mount it on the A frame, I have the bracket to fit it there. My question is, how do you run the cable through the hole in the bracket? The only way I can see is to cut the cable, Is that ok to do? Will cutting the cable affect the GPS signal strenth?

Dirk Diggler · 10 December 2005, 18:01

Why mount it on the frame, just stick it inside the console and it'll work ok! With the satellites so many thousands of miles away, another 4 foot closer isn't gonna make much difference!

Mike B · 10 December 2005, 18:22

Quote:

Originally Posted by Jieboy

I have been fitting my new Garmin 128 GPS today, everything was going ok until i got to the aerial. I am going to mount it on the A frame, I have the bracket to fit it there. My question is, how do you run the cable through the hole in the bracket? The only way I can see is to cut the cable, Is that ok to do? Will cutting the cable affect the GPS signal strenth?

It would depend on the bracket you have - Glomex brackets have a slot rather than a hole so you can lay the cable into the bracket without cutting it and then the unit screws together.

Personally I wouldn't cut the wire I don't think it would cause too much degredation in the signal but its then a weak link in the chain for moisture to get into. So if you do do it make sure it is made off well and sealed.

DD's suggestion sounds good to me but make sure there is no metal or human body obscuring the view of the sky.

Mike

Jieboy · 10 December 2005, 19:20

With my boat being less than 5m long, I need all the space I can get. Thats why I am gonna mount it on the A frame, out of the way. I also think it looks better. So I can cut it then, solder it back together then heat shrink it? Thanks for the fast replys.

Dirk Diggler · 10 December 2005, 20:30

Quote:

Originally Posted by Jieboy

So I can cut it then, solder it back together then heat shrink it? Thanks for the fast replys.

Suppose it'd be ok, but cutting the plug off and replacing it would be the best way!

roycruse · 10 December 2005, 22:56

If you cut the cable the gps antenna warrenty is void so bear that in mind - can you post some pictures of what you have so i can see exactly what the issue is.

Whilst you will probably in the most part get away with moutning the gps antenna elswhere the antenna will function best up on the a frame - the clearer path to the sky its got the better.

Rogue Wave · 10 December 2005, 23:13

is the antenna in a car GPS more sensitive than a seperate antenna as supplied with most marine units

roycruse · 10 December 2005, 23:40

Quote:

Originally Posted by Rogue Wave

is the antenna in a car GPS more sensitive than a seperate antenna as supplied with most marine units

Most modern ones yes !!!

Most modern in car sat nav systems use GPS receivers with the SIRF chip sets.

Traditional GPS systems used to ignore weaker satellite signals as they were potentially rebounds from terrain or building and would only take a fix from the stronger (direct) signals received.

SIRF however processes ALL the signals even the weaker potentially rebounded ones and based on analysing several readings calculates with some fantastic bit of software the most likely fix.

The SIRF system is ideal for use in cars where the receiver is traditionally mounted in side the vehicle and the vehicle its self is often in and out of hostile terrain (well hostile to satellite signals anyway) as it can maintain accurate fixes with far fewer and far weaker signals form the satellites.

As far as I know - marine gps do not use the SIRF chip sets in the GPS recievers as having to deal with weaker signals in the open ocean never occurs.

DJL · 10 December 2005, 23:51

Quote:

Originally Posted by roycruse

As far as I know - marine gps do not use the SIRF shipsets in the GPS recievers as having to deal with weaker signals in the open ocean never occurs.

Garmin are using the SiRF architecture in some of their new products - no idea which though.

Biggles · 11 December 2005, 01:18

I thought that Antenna clamped over an A Frame. Am I wrong.

Biggles · 11 December 2005, 01:19

Don't cut the bracket. Sit back and work out a way round it. maybe you might like to post some photos.

Biggles · 11 December 2005, 14:13

Quote:

Originally Posted by Jieboy

I have been fitting my new Garmin 128 GPS today, everything was going ok until i got to the aerial. I am going to mount it on the A frame, I have the bracket to fit it there. My question is, how do you run the cable through the hole in the bracket? The only way I can see is to cut the cable, Is that ok to do? Will cutting the cable affect the GPS signal strenth?

If you want to swap it for one with a built in antenna I have one.

Jieboy · 11 December 2005, 19:05

Decided not to cut the wire, instead, I will cut a slot from the start of the threaded section down to the hole. This will allow the wire to be layed into the bracket. Problem solved...... I hope? Sorry Biggles but I have already fitted the unit, just the aerial to do.