Sat nav marks

[oldessox]

I've plotted quite a few wrecks over the last couple of years following Norman's tutorial , this year however, the wrecks I marked out last year and the year before seem to have moved
I don't imagine they will have physically moved , but the marks on my plotter and the humps and bumps on my sounder don't coincide any more , they all seem to be about 80ft or so out
Anybody else ever had a similar phenomenon ?

 

[Kev1n]

No, I’ve not noticed that Ray. Could you have changed your GPS set-up, maybe to a different chart datum? Most charts are set up to be read on the WGS84 setting.

 

[oldessox]

I don't know kevin, it's really annoying me, I'll have to spend a bit of time looking at the settings, see if I've changed something I shouldn't have.

 

[Norman]

If somethings changed ray (or maybe a new plotter) at least when you find one "exactly" all the rest will be same distance and direction away from originals ...

norm

 

[oldessox]

If somethings changed ray (or maybe a new plotter) at least when you find one "exactly" all the rest will be same distance and direction away from originals ...

norm

It's weird Norman, my marks were set by the sounder , which is in the same unit as the plotter , over the last two seasons , this season I get to a wreck by the plotter and there's nothing there on the sounder, the wreck has "moved "
The marks are still pretty close , but I'm going to have to delete them all and start again if I can't find any settings changed on the plotter.
It got to the point earlier on in the season where I was glad to snag on the wreck because it confirmed it was actually there
I've got a written log with them all in , I'll have to check them too