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AusRick
26th June 2009, 07:25 PM
Hi folks,

Just grabbed a new Garmin 60CSx bundled with a cycle mount, windcreen mount for the car, carry case and 8Gb data card.

They threw in a 'no name' external antenna with the deal to connect to the MCX socket on the Garmin. They didn't carry the Garmin brand antenna (GA 27C)

One of the uses for the new GPS is to log traces for the Open Street Map project and I want to get the best possible accuracy with the data logging.

Can anyone recommend a really good external antenna? Who's purchased something and been really happy with the reception improvements ? Name names and prices please.

I'm trying to sort out the spin and get a really good one.

Cheers

Michael
26th June 2009, 07:47 PM
My advice, save your money, it will be fine without.

I found the external antenna improved the accuracy of my old 60 in the car.
However my 60Cx is very accurate all the time & the external antenna makes little difference.

Wahroonga Farm
26th June 2009, 08:29 PM
Do a test with and without on the 'sat capture screen'.

I'd be surprised if there was an improvement in most situations. The loss in the cable is the problem.

.... as Michael has already said. :)

Dooghan
26th June 2009, 10:56 PM
I've never seen any improvment in my 60CSx with the external antenna. Forget it and use the money on something else.

AusPak
27th June 2009, 12:23 AM
Hi folks,

..............

One of the uses for the new GPS is to log traces for the Open Street Map project and I want to get the best possible accuracy with the data logging.

.........

Cheers

The basics of the GPS system ......... if you get a lock on at least 4 satellites then your accuracy will be as good as it gets within reason. An antenna will give you better signal strength in more difficult locations, like under a heavier cover of trees.
I personally have never noted any difference between my
60CS and an external antenna running software on the laptop when tracked over the same roads and I have done a lot of tracks for OSM.

:hatoff

Nicko
27th June 2009, 12:25 AM
External Antenna does not improve accuracy it just helps you get those weak signals when the crappy old GPS engines of years gone by could not detect them properly. The current crop of GPS do NOT need an external antenna. Let me guess, Ryda?

AusRick
27th June 2009, 07:38 AM
Thanks everyone for the info.

Seems the consensus is that external antennas provide no real benefit and are not required for current model GPS units.

I've read on this forum where people logging traces for Open Street Maps use external antennas located to the right of their vehicle to get the most accurate track logs.

Certainly when I make a significant turn in direction, the GPS will wander for a short while and then return to a 3-5 metre accuracy. Obviously doing the trace work on clear sky days will bring the best results.

When adding the data to OSM and visual reference materials are available (such as Yahoo satellite imagery) then I can 'normalise' the trace results from my GPS, however most of my work is done in areas where sattellite imagery is not available or not of sufficient resoultion to be useful.

Has anyone experienced one of these RV76 GPS High Gain Antenna (http://www.gpsoz.com.au/RV16.htm) from GPSOZ?

Niko: I did make my purchase from Ryda, however the antenna was a topic I raised after reading forum posts here. Extensive searching online could not reveal cheaper listed prices for Australian stock anywhere. I put together 11 items to get in a single purchase hoping to negotiate further instore. They discounted their online prices by another $200 and I walked out with all 11 items (and a free antenna). From a business point of veiw, they may be tough competitors, but from a buyers point of veiw, they are hard to go past.

Cheers,

Rick

cuvier100
27th June 2009, 08:58 AM
In heavy wooded (i.e. when the track is covered by overhead branches) areas an external antenna is a must.

Mike

Nev
27th June 2009, 09:52 AM
In heavy wooded (i.e. when the track is covered by overhead branches) areas an external antenna is a must.

MikeOn your GPSMAP 60C - Yes.
On your GPSMAP 60Cx - not neccessasry and a waste of effort.