Accuracy on Garmin 76CS

[+Roaring_Fork]

Hi,

 

I have been caching for a short time and have found 29 caches. I am still trying to figure it out and have a question regarding accuracy.

 

My Garmin 76CS usually shows a location + - 8 to 20 feet but when I'm standing on a cache it will show the location around 30 to 70 feet away to the West using the compass. Is there a way to fix this or am I doing something wrong? I have downloaded everything from Garmin but it still has the problem. I have also tried WAAS enable and disabled but get the same result.

 

Thanks in advance for your help. I have really enjoyed taking my kids (4 and 6 years) out!!!

 

Sincerely,

Greg Knott

Roaring_Fork@msn.com

[+lacazg]

It could be that the accuracy of the owners GPSr is off by 20, this could account for you being off by that much. Or the cache could have slowly migrated from people setting it down in the wrong location.

[+briansnat]

30 feet off is quite common. Even if your unit has pinpoint accuracy (and it doesn't) the unit of the person who placed the cache also had an accuracy of about 10-30 feet. 70 feet is not unheard of, but unusual.

 

If your unit is consistently off 70+ feet there may be a problem. If it's usually off 10-40 feet and 50+ occasionally, then that is normal and nothing to be concerned about

[+Night Stalker]

The very first find I had with my GPS took me within 1 foot of the cache. I figured that this geocaching thing was a snap. I have never been that close again. Normally I am within 20' of a cache, but not necessarily at first. When It get close I will start searching and let my GPs continue to ponder. Over a period of time it refines its position until I am closer. This will take 5 to 10 minutes, and many cachers dont have the patience, but it works.

[+cache_r_joe]

I agree with Night Stalker. I usually don't find the cache right away. About 5 to 10 minutes later the gps is sending me to a slightly different location that it did originally and that is usually where the cache is. I have thought of sitting the gps down on a stump and let it settle down while I scope out the area, then come back and let it guide me there. Might work.

 

Joe

[+paulmc]

I too have found that setting the gps down (like on a stump) for a few minutes gives it a better fix. I've used this method several times when I'm having a hard time finding the cache. It's also common practise when doing high precision gps work such as land surveying.

 

paulmc

[+Roaring_Fork]

Thank you all for your responses. You have been very informative and helpful.

 

Greg

[+Thrak]

With the CS make sure you calibrate the compass often if you use the electronic compass. You MUST recalibrate it when you change the batteries but you "should" recalibrate it fairly often anyway.

[+Roaring_Fork]

With the CS make sure you calibrate the compass often if you use the electronic compass. You MUST recalibrate it when you change the batteries but you "should" recalibrate it fairly often anyway.

 

Good tip, Thanks.

Greg

[+Cardinal Red]

I have tremendous confidence in my GPSmap 76CS. It's not perfect (no consumer grade GPS is), but it consistantly puts me in the area where I need to be. Any perceived error seems to be randomly distributed. Not always off in one direction. Nobody has suggested tracking down an ADJUSTED benchmark in your area. That's going to be the best indication of accuracy available to you.

 

Control points that are used for horizontal control have much more accurate coordinates. (In some cases, those coordinates can seem almost hyper-accurate.) If, on the benchmark page, it says "location is ADJUSTED", then you are looking for a horizontal control point. Most of these have been included in a nationwide network adjustment to obtain state-of-the-art precision, and the coordinates can be much more accurate than any handheld GPS can measure (within a few millimeters).

 

datasheet->BY POINT RADIUS

[+dew cache]

With the CS make sure you calibrate the compass often if you use the electronic compass. You MUST recalibrate it when you change the batteries but you "should" recalibrate it fairly often anyway.

 

Just curious why that is. I have a 76CSx and I am having problem with the compass going away completely including the marks on the outside of compass when I am in the cache area and looking for the cache. I can set it down on the ground and it continues to work. I can power it off and on or recalibrate it to get the compass back. I talked to Garmin support and the only thing they can tell me is to download the latest software which didn't do a thing to help it and now it is over a year old and out of warranty and they want $200 to look at it. Does the 7nC series have a problem with the compass?

[+tangelus]

With the CS make sure you calibrate the compass often if you use the electronic compass. You MUST recalibrate it when you change the batteries but you "should" recalibrate it fairly often anyway.

 

Just curious why that is. I have a 76CSx and I am having problem with the compass going away completely including the marks on the outside of compass when I am in the cache area and looking for the cache. I can set it down on the ground and it continues to work. I can power it off and on or recalibrate it to get the compass back. I talked to Garmin support and the only thing they can tell me is to download the latest software which didn't do a thing to help it and now it is over a year old and out of warranty and they want $200 to look at it. Does the 7nC series have a problem with the compass?

 

I have a brand new 76CSx and experienced the same problem. Yesterday was the first day I used it out in the field and found that the compass marks disappeared, too. I thought it may have been caused by bumping it on my leg as I clibmed around. I attached the tether strap to my belt and it was swinging around quite a bit. I needed to re-calibrate before it would work again.

 

What software version did you download? My new device has Software Version 3.30 and GPS SW Version 2.90.

 

Tom

[+dew cache]

With the CS make sure you calibrate the compass often if you use the electronic compass. You MUST recalibrate it when you change the batteries but you "should" recalibrate it fairly often anyway.

 

Just curious why that is. I have a 76CSx and I am having problem with the compass going away completely including the marks on the outside of compass when I am in the cache area and looking for the cache. I can set it down on the ground and it continues to work. I can power it off and on or recalibrate it to get the compass back. I talked to Garmin support and the only thing they can tell me is to download the latest software which didn't do a thing to help it and now it is over a year old and out of warranty and they want $200 to look at it. Does the 7nC series have a problem with the compass?

 

I have a brand new 76CSx and experienced the same problem. Yesterday was the first day I used it out in the field and found that the compass marks disappeared, too. I thought it may have been caused by bumping it on my leg as I clibmed around. I attached the tether strap to my belt and it was swinging around quite a bit. I needed to re-calibrate before it would work again.

 

What software version did you download? My new device has Software Version 3.30 and GPS SW Version 2.90.

 

Tom

 

Software version 3.30 and gps sw version 2.90

[pstock44]

With the CS make sure you calibrate the compass often if you use the electronic compass. You MUST recalibrate it when you change the batteries but you "should" recalibrate it fairly often anyway.

 

Just curious why that is. I have a 76CSx and I am having problem with the compass going away completely including the marks on the outside of compass when I am in the cache area and looking for the cache. I can set it down on the ground and it continues to work. I can power it off and on or recalibrate it to get the compass back. I talked to Garmin support and the only thing they can tell me is to download the latest software which didn't do a thing to help it and now it is over a year old and out of warranty and they want $200 to look at it. Does the 7nC series have a problem with the compass?

 

I have a brand new 76CSx and experienced the same problem. Yesterday was the first day I used it out in the field and found that the compass marks disappeared, too. I thought it may have been caused by bumping it on my leg as I clibmed around. I attached the tether strap to my belt and it was swinging around quite a bit. I needed to re-calibrate before it would work again.

 

What software version did you download? My new device has Software Version 3.30 and GPS SW Version 2.90.

 

Tom

 

Software version 3.30 and gps sw version 2.90

 

I also just bought and started using my 76CSx. So far the only troubles I've had are learning how to get it to do everything I want. It seems easy to use but it does so much it just seems a little complicated at times. My compass seems to be working great and as far as the original topic of this thread is concerned I found that with the WAAS enabled the GPS was usually showing and accuracy of 6-15 feet. I tried wandering in circles for a few minutes and I could easily center up on the waypoint.