Garmin Oregon screwing up first point in every track

[Ham]

Here's an extract from my  current.gpx, it shows the crossover from one day to the next. The previous ride ending at home being switched off, the next starting in Berkhamstead. See the comments for the problem

<trkpt lat="51.5595997218" lon="0.0416122098">
<ele>24.17</ele>   // elevation is barometer driven
<time>2013-07-13T14:19:11Z</time></trkpt></trkseg></trk> // yep that's the date and time

<trk><name>Current Track: 14 JUL 2013 11:25</name> // rock'n'roll the next day

<trkseg>

<trkpt lat="51.5596550424" lon="0.0417460687"> // NO NO NO - this is home!!!
<ele>120.30</ele> /// BUT THIS IS WHERE I WAS STANDING!!! WTF?
<time>2013-07-14T10:25:45Z</time>
</trkpt>

<trkpt lat="51.7823275086" lon="-0.5578589905"> // Ah, look, it's found out where I am
<ele>119.82</ele>
<time>2013-07-14T10:25:46Z</time>
</trkpt>

<trkpt lat="51.7824092321" lon="-0.5578935239"> // All OK now
<ele>121.26</ele>
<time>2013-07-14T10:25:59Z</time></trkpt>

So, each track is connected to where the device was switched off last. I can edit manually, but it is a real pain.

Anyone seen this ? It's not an isolated incident.

[hbunnet]

It doesn't do this if you reset the track  after the gizmo has found its new location.

[Auntie Helen]

Yes, I don't reset the track until I'm sure it's picked up my new location (by checking the map or that it's showing a speed)

[Kim]

Ah, could this be related to the annoying trip odometer behaviour in the new eTrexes?  They seem to like adding distance travelled while switched off.

[Ham]

It doesn't do this if you reset the track  after the gizmo has found its new location.

Given the time it takes to find itself in a new location, this is not always practical.

Plus the problem is, it claims to have found itself - that has to be cr@p - It is recording a data point that it is imagining. The altimeter proves where it is, the coordinates are just bollocks. It only starts recording when it has worked out where it is, so why the &%££$ does it make it up?

[Kim]

Smells like an off-by-one error in the algorithm.

[Auntie Helen]

It's remembering the previous location and automatically adding that when you first turn it on.

I find mine finds the new location within about 10 seconds. I switch it on, attach it to the trike, wheel the trike to the road, reset the trip and then off I go, no probs.

If I change country (i.e. using the ferry) it may take longer to fix its location.

[Kim]

It's remembering the previous location and automatically adding that when you first turn it on.

I find mine finds the new location within about 10 seconds. I switch it on, attach it to the trike, wheel the trike to the road, reset the trip and then off I go, no probs.

That's fine.

What bugs me is when I ride to a station, switch it^[1] off, get a train somewhere, switch it on, ride around for a bit, then notice the odometer's added the crow-flies distance of the train journey (it also adds a line to the track log).  The Vista HCx would, on the other hand, not record any distance while switched off, and the track log would have a gap in it - by far a more useful behaviour.  I'm getting better at remembering to save and reset the track, but this means I don't get overall totals and averages for the day's cycling.


_{[1] eTrex 30}

[Auntie Helen]

When I first got the Oregon it bugged me that I couldn't switch it on and off from recording short of powering the whole thing off. Previously I had the Edge which you had to press to start.

Mind you, I never forget to 'start' the Oregon so it's always recording, even if, as Kim says, you get railway journeys included if you forget to save the track and start a new one. However it's now second nature for me to do this and I haven't mucked it up in about two years. If ever I am turning it off knowing that it'll be switched on in a new location I save the track; when I switch it on in the new location I give it ten seconds and then clear the current track, knowing it's starting a new one.

It is something to get used to, though. But it soon becomes automatic.

[Kim]

It should, ideally, be a configurable behaviour.

I think it's worse on the new eTrex, because it's changed a behaviour that was consistent all the way from the original yellow eTrex to the Vista HCx, that eTrex users have come to expect.  The Edge series are another kettle of fish entirely, and their start/stop behaviour makes sense in their own context.

Incidentally, you can stop recording without switching off on an eTrex by turning the GPS off from the satellite menu (this is labelled as 'Demo mode' on the new eTrexes) - possibly the same works on an Oregon, given the general similarities.  I tend to do this at the end of a ride to stop the clocks ticking while I get round to noting things down for bikejournal.

[frankly frankie]

There's "hot start" "warm start" and "cold start".

If you turn it off to change batteries, or for a short control stop - that's a hot start.  It's quick (seconds), and it assumes it hasn't moved since you switched it off, and that its clock is still reasonably in sync.
If you turn it on out of the bubble pack - or after a very long period (say a couple of months) - that's a cold start.  It can take up to 20 minutes and it assumes nothing.

Mostly - including an overnight break, and even if you've just travelled halfway round the world - it's a warm start.  It's fairly quick (usually less than 2 minutes) and it assumes it hasn't moved since the last time, but that its clock must be resynced.  If after syncing the assumption that it hasn't moved turns out to be incorrect - still it has dumped an initial spurious trackpoint at the old location. 

[Ningishzidda]

For info.

A behaviour I faced with TomTom rider is that at first switch-on each day, the unit adds the straight line distance from ‘Home’ immediately. In the TomTom rider world, ’Home’ is the depot the dispatch rider operates from and that’s where his shift starts.

The correct procedure for recording the estimated distance of an Audax is to re-allocate ‘Home’ as the start of the Audax when the ITNs are imported sometime the previous evening.
If forgotten, a reset of odometer values is required, which screws up the monthly, annual and lifetime trips. Done many times 

Switching off, moving and switching on half way through an Audax produces the addition of the straight line distance from the unit’s last known location.

But, as is already known, distance recordings on GPS units are ALWAYS lower than actual reality due to ‘stringing' between log points.

I don’t take much notice of trip distance. Its ‘Distance to next cake’ I am concerned with. 

[Greenbank]

There's "hot start" "warm start" and "cold start".

Indeed, this goes into more detail than you could possibly want: http://www.gpsinformation.net/main/gpslock.htm

[Kim]

I don’t take much notice of trip distance. Its ‘Distance to next cake’ I am concerned with. 

Trip distance still works when the unit isn't doing any navigating (eg. when you're navigating by routesheet, or in pedal & follow mode on a group ride, or mindlessly bimbling or whatever).  Which means it can be useful for working out when you're going to need to apply cake.

[Ningishzidda]

I don’t take much notice of trip distance. Its ‘Distance to next cake’ I am concerned with. 

Trip distance still works when the unit isn't doing any navigating (eg. when you're navigating by routesheet, or in pedal & follow mode on a group ride, or mindlessly bimbling or whatever).  Which means it can be useful for working out when you're going to need to apply cake.

On Audaxes, someone invariably asks “How far have we ridden” knowing most riders have ‘Distance’ displayed. Someone replies “x km.” Then the questioner asks “How far to go then?”

Then I can give an answer to the question the guy wanted to ask in the first place.

[Ham]

I don’t take much notice of trip distance. Its ‘Distance to next cake’ I am concerned with. 

Trip distance still works when the unit isn't doing any navigating (eg. when you're navigating by routesheet, or in pedal & follow mode on a group ride, or mindlessly bimbling or whatever).  Which means it can be useful for working out when you're going to need to apply cake.

On Audaxes, someone invariably asks “How far have we ridden” knowing most riders have ‘Distance’ displayed. Someone replies “x km.” Then the questioner asks “How far to go then?”

Then I can give an answer to the question the guy wanted to ask in the first place.

....of course you could have distance travelled and distance to go displayed, or is that too easy?

[Ningishzidda]

I don’t take much notice of trip distance. Its ‘Distance to next cake’ I am concerned with. 

Trip distance still works when the unit isn't doing any navigating (eg. when you're navigating by routesheet, or in pedal & follow mode on a group ride, or mindlessly bimbling or whatever).  Which means it can be useful for working out when you're going to need to apply cake.

On Audaxes, someone invariably asks “How far have we ridden” knowing most riders have ‘Distance’ displayed. Someone replies “x km.” Then the questioner asks “How far to go then?”

Then I can give an answer to the question the guy wanted to ask in the first place.

....of course you could have distance travelled and distance to go displayed, or is that too easy?

Far too easy.

Incidentally, have you ever asked a rider at the penultimate control of a 400 "What size tyres are you using?" He won't have the foggiest.
Two numbers on a screen will lead to confusion, er sorry, ADD to confusion.   

[Ham]

Garmin support feedback:

Do a hard reset (hold top left of screen in Oregon while switching on)
Update software
Hope for the best

Pay us £86 if that doesn't work (we'll see about that)

Oh well, let's try

[bryn]

Garmin support feedback:

Do a hard reset

Yeah, that is their favourite response (doesn't fix any faults I have had, just loses all the settings).

--
Bryn

[fuaran]

I think it helps if you set it to auto-archive the track daily. Then it should clear the current track when you switch it on each day.
This usually seems to avoid wrong points at the start of the track.

Though it doesn't help if you are switching it on in several different places on the same day.