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Garmin GPSTC Datafield - to complement the Motion Simple Logger

Created by tbwonder tbwonder  > 9 months ago, 3 Apr 2020
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vosadrian
vosadrian

NSW

459 posts

17 Jun 2022 3:39pm
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sailquik said..

[b]vosadrian said....
(and has an axe to grind against any large corporation).



You are grinding one HUGE axe in your posts.


I've ground a few axes in my time!! But I have none to grind against Julien. I wish him the best with his product. I just wish he would not feel the need to post negative comment on his competition.
vosadrian
vosadrian

NSW

459 posts

17 Jun 2022 3:53pm
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segler said..
Timing circuitry has gotten extremely accurate while remaining really cheap. Positional accuracy is the problem. If speed is calculated from positional data, it is noisy. Max speeds are usually unrealistically too high.

Doppler speeds use the timing circuits, not the positional calculations, and are typically much more accurate. K888 states that doppler speed calculations even typically include kalman filtering.

K888 has also stated, from his studies, that pretty much all modern GPS chipsets measure speeds with doppler, but many (or most) of them record the speeds from positional data. To me this is crazy.

K888 examined a FIT file I sent him from my Timex Ironman GPS watch. He saw that my FIT file contained speed data taken from doppler, and recorded as such in the file. The Timex Connect app shows the max speed from these data, but Strava ignores speed numbers in my FIT file and calculates max speed from positional data; this max speed is always 10-20% higher and is not even realiistic.

I sent Strava an email asking them to change their programming to use speed numbers if the upload file already contains them.

GoldenCheetah does indeed use the speed numbers in the FIT file. I don't know about other apps.

You can read K888's stuff here:

logiqx.github.io/gps-guides/
logiqx.github.io/gps-guides/sessions/contacts/marr/


So basically, the speed accuracy from positional data would improve at the same rate as positional accuracy improves (since time is very accurate). So it is desirable in a non-doppler recording device to have better positional accuracy if you want better speed accuracy.

I'm not surprised Strava would not care about the speed accuracy. Strava is basically about getting the best time on a defined path or segment (that you stay within say 20m of that path) between a start POSITION and finish POSITION. They don't care what the speed reading is at any time along the path. They often list an average speed for the "segment", but that speed has nothing to do with the speed the device recorded. It is simply the calculated distance of the segment divide by the time for the segment. Strava is fantastic for cycling and running. I use it for my windsurfing also, but it is not ideal for that since it does not give the windsurfing stats. But they do accept my device.

I have occasionaly had segment match issues because of positional error. Often when I am riding through gorges with poor GPS signal (steep hills on both sides). This is because my path wanders outside the allowed distance from the segment. It can be annoying when this happens if you put in a big effort trying to get a PR.
segler
segler

WA

1658 posts

18 Jun 2022 11:32pm
Back on topic. Above tbwonder said, "Garmin Instinct Watches do not support Datafields from the IQ Store."

Can you comment? Is the firmware, or data structure, or low memory?
tbwonder
tbwonder

NSW

735 posts

20 Jun 2022 8:47am
The Instinct watches are generally a lower level specification (and price) than other Garmin watches. Garmin has made the decision to not support any aftermarket datafields on this series of watches. So they have no internal memory allocated to datafields, I think you may be able to download different watch faces, but that is all.
segler
segler

WA

1658 posts

22 Jun 2022 12:15am
Thanks. I was wondering. I will stick with my Fenix 5X.
tbwonder
tbwonder

NSW

735 posts

3 Jul 2022 7:23pm
I have added GPSTC V4 support for the latest Garmin Watches, the 255 and 955
There are a few things to watch out for. regarding the 255 variants
The 255 comes in 4 versions. (255, 255s, 255 Music and 255s Music)
For some reason Garmin have chosen to use an old screen with only 218 pixels for the 2 "s" versions of the watch. I do not intend to support these 2 models. The other 2 (255 and 255 music) are supported. There is no need to buy the music version of the 255 (as was required with the 245) the base model is just fine.

Table of all supported watches for GPSTC V4 (Version 4.25)




tbwonder
tbwonder

NSW

735 posts

27 Jul 2022 9:26am
I have created an exact copy of my "GPSTC V4" datafield called "GPSTC V4 (Foil)".
This allows you to install both datafields on your watch in two separate Activities.
Then you can set the user settings in one for speed sailing sessions and in the other for foiling sessions.

My settings are


BSN101
BSN101

WA

2378 posts

27 Jul 2022 3:03pm
Garmin has a sale on now. I missed out on 245 but got a 745 half price. Will be having a sesh in 2 days. Woohoo
BSN101
BSN101

WA

2378 posts

29 Jul 2022 8:49am
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BSN101 said..
Garmin has a sale on now. I missed out on 245 but got a 745 half price. Will be having a sesh in 2 days. Woohoo


JBHI sale now. Half price Garmin 245 Music
tbwonder
tbwonder

NSW

735 posts

29 Jul 2022 4:46pm
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BSN101 said..



JBHI sale now. Half price Garmin 245 Music


245 Music AU$289
This is a great deal. The 245Music has been recently superseded by the 255 which is a $600 watch.

The 255 will be the cheapest watch in the Garmin line up to support my datafields.
As it is a new model do not expect to see discounts for a year or two.
kato
kato

VIC

3513 posts

27 Aug 2022 3:17pm
Just joined back into the Garmin club with a Fenix 6 Pro $575 .Now let's see if I can navigate the tech stuff to get it to work. At least the post is a bit slow and it will give me some research time before it gets here.
AusMoz
AusMoz

QLD

1510 posts

27 Aug 2022 6:25pm
Im having major issues downloading to my garmin 735 xt. It says installed but doesn't show on my screen apps. Tried the YouTube fix etc. Still no bloody success!!!!!

The garmin connect on my phone says its there but doesn't display on my watch?????
tbwonder
tbwonder

NSW

735 posts

27 Aug 2022 10:33pm
I have had several requests to add the Venu Version 2 watches to the list of supported devices for GPSTC V4.
I have added:
Venu 2 and Venu 2 Plus (Note the Venu 2S is not supported)
As usual this code has only been tested on the simulator not on an actual watch.
Latest Version is V4.26 (foil version also updated)

See the latest updated instructions at www.haigh.id.au/GPSTC.htm

AusMoz, TheGarmin 735XT does not support the GPSTC V4 datafields, you can of course use the earlier datafields. The above instructions go through the process for installing the datafield within a user created Activity.
AusMoz
AusMoz

QLD

1510 posts

28 Aug 2022 1:17pm
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tbwonder said..
I have had several requests to add the Venu Version 2 watches to the list of supported devices for GPSTC V4.
I have added:
Venu 2 and Venu 2 Plus (Note the Venu 2S is not supported)
As usual this code has only been tested on the simulator not on an actual watch.
Latest Version is V4.26 (foil version also updated)

See the latest updated instructions at www.haigh.id.au/GPSTC.htm

AusMoz, TheGarmin 735XT does not support the GPSTC V4 datafields, you can of course use the earlier datafields. The above instructions go through the process for installing the datafield within a user created Activity.


Sent you a message.
flatchat
flatchat

WA

89 posts

21 Sep 2022 6:21pm
Hi. Has anyone else noticed that the results when downloaded onto the Garmin app, has all been rounded to a whole number. I'm using the Garmin Fenix 5. Is there a fix for this? Tia.
tbwonder
tbwonder

NSW

735 posts

22 Sep 2022 8:38am
Yes I had noticed this. Not sure when it changed. Looking back at some early posts in this forum, I can see screen shots of the phone app and PC app and they both displayed one decimal place.

Now the phone Connect app shows no decimals places and the same Activity in Garmin Connect on your PC shows 3 decimal places.
So it is not the download process, but the display process in the different apps. I use Windows and iphones, it would be interesting to hear what other users are seeing in the Apple Mac world and android phone world.
I don't think there is much I can do to change this, except possibly to add an option to multiply the results by 10.
flatchat
flatchat

WA

89 posts

22 Sep 2022 8:31am
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tbwonder said..
Yes I had noticed this. Not sure when it changed. Looking back at some early posts in this forum, I can see screen shots of the phone app and PC app and they both displayed one decimal place.

Now the phone Connect app shows no decimals places and the same Activity in Garmin Connect on your PC shows 3 decimal places.
So it is not the download process, but the display process in the different apps. I use Windows and iphones, it would be interesting to hear what other users are seeing in the Apple Mac world and android phone world.
I don't think there is much I can do to change this, except possibly to add an option to multiply the results by 10.


Ok thanks. Btw I was using this app side by side with my GW52 yesterday, dinging and found the 2s on the Fenix was 2knts higher then the gw52. I was surprised by this difference. Great app btw??
K888
K888

248 posts

28 Sep 2022 6:01am
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flatchat said..


Ok thanks. Btw I was using this app side by side with my GW52 yesterday, dinging and found the 2s on the Fenix was 2knts higher then the gw52. I was surprised by this difference. Great app btw??


It's not uncommon for some Garmin devices to produce 2s results which are 1 or 2 knots higher than the GT31, GW-52, GW-60 or Motion.

I've seen this when doing device comparisons so it'll be the watch itself, rather than the data fields.

Here is just one example session - logiqx.github.io/gps-guides/sessions/contacts/kisg/
flatchat
flatchat

WA

89 posts

28 Sep 2022 11:51am
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K888 said..



flatchat said..



Ok thanks. Btw I was using this app side by side with my GW52 yesterday, dinging and found the 2s on the Fenix was 2knts higher then the gw52. I was surprised by this difference. Great app btw??



It's not uncommon for some Garmin devices to produce 2s results which are 1 or 2 knots higher than the GT31, GW-52, GW-60 or Motion.

I've seen this when doing device comparisons so it'll be the watch itself, rather than the data fields.

Here is just one example session - logiqx.github.io/gps-guides/sessions/contacts/kisg/


yes. I've experienced this first hand from the example above. But this one didn't give me any confidence in the F5. About a month ago, my F5 reported a 28knt 2s whilst out dingin. I didn't claim it and wouldn't have expected to reach 20knts in those gnarly conditions. I did dream for awhile though
BSN101
BSN101

WA

2378 posts

5 Oct 2022 9:45am
Are there instructions out on how to get the data off the Garmin app & into KA72. Cheers
Dezza
Dezza

NSW

955 posts

5 Oct 2022 5:24pm
Someone else may have a better way, but open the activity on Garmin Connect on a pc, download the file using "Export to GPX" under settings, then go to KA72 and upload it, file should be in your downloads folder
berowne
berowne

NSW

1555 posts

5 Oct 2022 9:17pm
Rigth on Dezza.
You can even do it on your phone at the beach!
tbwonder
tbwonder

NSW

735 posts

6 Oct 2022 10:31am
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berowne said..
Rigth on Dezza.
You can even do it on your phone at the beach!


I don't believe it is possible to export data files from the Garmin Connect phone app.
Dezza
Dezza

NSW

955 posts

6 Oct 2022 1:06pm
I think Berowne was referring to logging into the Garmin connect website on a phone via its browser to access the download/export from there. Although when you do there's an invite to open the app, ignore that and stay on the web version
Freeflight
Freeflight

119 posts

12 Oct 2022 7:38am
Hi guys
I think next time a deal comes up in AU on a garmin watch that works well with tbwonder's datafield I might grab one
Please post here next time anyone sees a discounted deal on a suitable garmin watch
open to budget 200-$500
thanks
Rod
AusMoz
AusMoz

QLD

1510 posts

14 Oct 2022 11:53am
I have to ask, are the new ballistic Garmin Fortrex wrist Gps ok for Gps Team challenge???? Xhunter has them on special
YP1
YP1

YP1

SA

136 posts

3 Jan 2023 9:09am
My garmin Fenix 5 has been a great addition I especially like the Hr 0ty & alpha data fields.
I havent used my watch since Oct 30 2022 when every thing was working great. 2nd Jan 2023 & Hr 0ty & Alpha all did not display, all results 0. only plug the watch into my computer to charge & I cant remember if it has done any "auto" updates. I think it must have as it now reports all up to date & sync OK. Any Ideas why 0 results for Alpha 0ty & Hour?
tbwonder
tbwonder

NSW

735 posts

4 Jan 2023 9:19pm
Which version are you using. There is a version number on the launch screen.
YP1
YP1

YP1

SA

136 posts

6 Jan 2023 8:28am
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tbwonder said..
Which version are you using. There is a version number on the launch screen.


V2 10th March 21
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