Oregon 550T Accuracy - HELP!

[+Blues Man]

I had a Garmin Colorado for years and never had a problem with accuracy. The Colorado was always within 30 feet and often, under 10 feet to my destination. The Colorado died and I replaced it with the Oregon thinking that I would not have to relearn a new manufacturers device. But this Oregon 550T is showing a Distance to Destination of 60 to 90 feet away. Funny thing is, the cache shows up pretty accurately on the map screen. Its just the Distance and the Arrow that are off. I read everything I could and have updated firmware. I am using the geocaching profile with the off road setting. I'm hoping that someone knows of a setting on the Oregon that I need to adjust. Help because this Oregon is not geocaching friendly.

[+Bear and Ragged]

But this Oregon 550T is showing a Distance to Destination of 60 to 90 feet away. Funny thing is, the cache shows up pretty accurately on the map screen. Its just the Distance and the Arrow that are off.

 

Same distance and direction off each time?

 

Could be the Datum is set wrong.

[+Gitchee-Gummee]

Check your settings:

 

Setup > Routing > Guidance Method > choose Off Road;

 

-AND-

 

Same access directions -- make sure that Lock on Road is OFF.

This is on page 28 of the manual.

 

Seen that before here in the forums. You need to do both settings.

 

 

Otherwise, check Datum and Format set to: WGS-84 and HDD(D)° MM.MMM

Edited September 29, 2014 by Gitchee-Gummee

[+andyakashrek]

I had a similar problem with my 550t, I sorted mine out by setting it to use normal gps only, I turned off waas, and then it was like using a different unit. Search forum for do you use waas or egnos.

I also updated firmware to latest available but I am convinced that turning off waas is the way to go. However I am in uk ymmv.

Try it, you have nothing to lose, I would try the gps setting first before firmware, it's easy to downgrade if it doesn't make a difference.

I know people will say leave waas on but for me it really does make a difference with it switched off.

[insig]

It sounds like the map datum is wrong as pointed out by others above.

[+New Jersey TJ]

Have you tried checking the accuracy against a benchmark? You cannot rely upon the accuracy of a cache.

 

I'm not sure if the 5x series tracks Glonass, but if it does and you have Glonass tracking turn on, try turning it off. Some have reported increased accuracy with that setting turned off.

[+ecanderson]

I'm the 3rd vote for datum. Assure that you're in WGS84 mode.

[+Blues Man]

Thanks to all for your suggestions. Checking my Oregon 550T and I verified that I have the right datum, WGS84 and it is set for off road use. I will try the suggestion of changing from the WAAS/EGNOS setting to the NORMAL setting and see if that helps.

[+Blues Man]

Yep... Lock On Road is OFF.

[+Blues Man]

FIXED! Looks like Gitchee-Gummee was the closest to figuring this out. I still don't know why this is not posted anywhere on Geocaching or Garmin considering that the Oregon is a popular GPSr. Anyway, as G-G points out, there are 2 places where you have to choose off road. One is obvious, the other is not. Turn LOCK ON ROAD off. Thats the easy part. The hard part is that deep within the Setup is a place where you have several options such as Hiking, Mountaineering, etc. You would think that Hiking would cover it... but no. You need to choose the option called Direct Routing. Once this was picked the Oregon works like a charm for geocaching.

 

Heres another thing about the Oregon, and maybe other Garmins as well. It will take 12 satellites. If you enable WAAS, it holds the last 2 slots for WAAS satellites. If it finds them, you can expect greater accuracy than without WAAS. BUT.... If it cannot find WAAS satellites, then the last two slots remain open - it will not fill them with regular satellite feeds and you essentially lose the accuracy that you could have had with WAAS off and a full 12 regular sattelites. In most cases, you can get WAAS in open areas, but will have some difficulty under tree cover and near buildings. Bottom line.... best to turn WAAS on in open areas and off at other times. This had nothing to do with the Oregon problem I had above, I just wanted to share this info.

[+Red90]

Datum will only matter if the coordinates were put in manually, which I serious doubt anyone ever does. If they are put in electronically, you can change the datums to anything you want and it will not affect finding the cache.

[+ecanderson]

Datum will only matter if the coordinates were put in manually, which I serious doubt anyone ever does. If they are put in electronically, you can change the datums to anything you want and it will not affect finding the cache.

? The gpx entries do not supply datum information, so whatever datum is current when the gpx is loaded will be assumed relevant to the coordinates in the file.

However, it is true that once loaded, accidentally switching to another datum hurts nothing, though the coordinates displayed on the unit won't be the same as those on the cache page.