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decrepit said..
Peter, I think option 2 could happen,

Back in April I asked for comparison files from the FR255, but none have arrived as yet.
All we need is proof of the devices' accuracy and it can be approved.

Has the time passed for more and more analysis of the
Garmin watch ? The Garmin watches that use both multiple GNSS systems and dual frequencies and have been proven to be accurate.

More importantly people need to be able to purchase a device.

There seems to be no argument here as we have no other option.

tbwonder or boardsurfr are you able to list the Garmin devices that have these particular GNSS systems ?

GPSTC committee are you able to approve these devices please.

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decrepit said..
Peter, I think option 2 could happen,

Back in April I asked for comparison files from the FR255, but none have arrived as yet.
All we need is proof of the devices' accuracy and it can be approved.

I have captured a lot of test data for the FR-255 this year - windsurf, windfoil and wingfoil. I can package it all up and upload to a shared drive for the benefit of the GPSTC technical guys. Most sessions, I wear a Motion mini on each arm, COROS APEX 2 Pro on my left wrist and FR-255 on my right wrist.

The impressive performance of the FR-255 appears to be due to the Airoha AG3335M chipset. It's crucial to use the right activity mode (windsurfing, kitesurfing, or other) and the right GNSS settings (multi-band or all systems). If you are using the GPSTC datafield then it's up to the user to configure the watch correctly. If you are using an app such as windsurfing application (ViVSurfer) or APPro (Scott Simms), it's up to the app developer to get the settings right because the Garmin API default to vanilla GPS.

I mentioned the Airoha AG3335M which is the mult-band / dual-frequency chipset. The Airoha AG3335MN is essentially the same chip, but supports NavIC (regional system for India) but lacks multi-band. During my testing, I have found comparable results using the non-dual band setting (but using all systems) although that can sometimes spike (although quite rare). I have yet to determine whether the dual-band setting really does prevent spikes. Not all systems + sats are dual band, so not all issues are detectable.

I've only had the opportunity to assess the FR-255 and Epix (gen 2) which are both equally good. It's my assumption (but yet to be proven) that other Garmins using the same chipset(s) will perform equally well. I have already confirmed that things like activity modes are implemented in the same way across multiple generations of garmin, regardless of the chipsets (MediaTek, Sony, Airoha). It's the performance of the Airoha that makes the newer watches so much more reliable.

I've documented every Garmin watch and which GNSS chipset they use at logiqx.github.io/gps-details/devices/garmin/watches/

As an aside, you get equally good performance from the newer COROS watches at times when you have a working firmware. There are only two models that are currently working properly though.

Lastly, the Airoha AG3335M and AG3335MN do generate accuracy estimates - 3D position + 3D speed +2D position + 2D speed. There is just no way to get them out of a Garmin device at this time.

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tbwonder said..

boardsurfr said..
Option2. Approve at least one device that is currently commercially available. This may require to change the "approval standards".

I don't believe that there is any requirement to change the approval standards. As there is no written requirement for a device to provide error data. Devices without error data have been approved before.

A point on my App. Whilst many people use my app for sailing and it does generate the six category results. These are all generated in real time on a tiny watch processor that is no match for GPSSpeedreader or other filtering programs. My program in no way changes the raw GPS data that produces the Garmin FIT file data. So the Garmin 255 could be approvd for GPSTC use with or without my app.

I don't believe the committee would approve just a single watch. It would most likely be for watches that use the same multiband technology.

Andrew,
I have the 255 but am only able to download GPX files. Results from GPX files often over report 2 sec results by 2 kts. How do I access the FIT file of a session so I can compare against my Mini Motion.

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John340 said..

Andrew,
I have the 255 but am only able to download GPX files. Results from GPX files often over report 2 sec results by 2 kts. How do I access the FIT file of a session so I can compare against my Mini Motion.

In Garmin Connect (Must be the Computer version, not on your phone)
From the selected activity click the little wheel in the top right and select 'Export File'
Annoyingly it will save the file in a ZIP folder.

You are correct if you export as a GPX then you will not get the doppler data

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tbwonder said..

John340 said..

Andrew,
I have the 255 but am only able to download GPX files. Results from GPX files often over report 2 sec results by 2 kts. How do I access the FIT file of a session so I can compare against my Mini Motion.

In Garmin Connect (Must be the Computer version, not on your phone)
From the selected activity click the little wheel in the top right and select 'Export File'
Annoyingly it will save the file in a ZIP folder.

You are correct if you export as a GPX then you will not get the doppler data

Andrew, I've done that but the fit file is very small (200 to 300 kb). I've tried uploading into KA72 and KA72 does not process the file. I may have a probelm with my settings? Do I use 0 or 1 for FIT file logging?

0 is usually off and 1 is usually on, so 1 would be my bet, but if that's where you have it, try 0 and see what happens.

Last resort read the manual which says:
"FIT File logging"Set to '0' if you wish to export the FIT file for use in other programs such as KA72 The default value is "1" this allows the category results to be written to Garmin Connect.

Unfortunately if my App tries to write the category results to the FIT file, KA72 no longer will read it. So if you want to post to KA72 then logging must be set to 0.

If GPSTC does approve certain Garmin Watches then I will probably make a special datafield just for approved watches which would have a few different settings.