Does GPS Go Off At Times

Here and on other sites there are a lot of comments about how bad phone program navionics has gotten lately. Mine is bad too. So yesterday I got frustrated and hooked up my good Lowrance unit in my truck, same results,?. My question is are there times that the government readjusts or does maintenance on it or is there something that would make it go wacky for a little while? Sounds crazy but my Navionics on my phone, well it wasn’t great, but it was still pretty close. And my Lowrance has always been spot on. I’m stumped, anybody else seeing this in your area?

There are times where the GPS satelites line up better and worse, which will affect accuracy.

Navionics was awful yesterday.

But, my google maps was still spot on, and since I’m mostly a weedline fisherman anyways satellite view saved my a$$.

This would tell me navionics has an issue, not the GPS system.

I pinned my house sometime ago, and I’m certainly not at my neighbor’s today.

Might have to each time out calibrate how far it’s off and to which direction and just use that as an offset if you will, to get accurate spots.

Perfect world we all go buy a portable mapping unit, and have everything spot on every day. For the little $$ that’s needed for this, I’ll live with it, but again ice fishing isn’t terribly important for me.

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Availability and alignment of satellites impact the precision of the GPS reading.

Also space weather events like solar storms affect how the Earth’s ionosphere “bends” the GPS signal as it passes through from the satellites. Consumer GPS units use can compensate for this bending variation under most conditions, but not all. This can be one of the biggest factors in day-to-day accuracy. Some software is better at “compensating” for this.

Most GPS software programs have a screen that displays current accuracy. Right now I’m looking at a precision farming program called Field Navigator and I see accuracy fluctuating between 14 feet and 24 feet. Which is not good, normally I see accuracy at 5 feet or less.

There must be somewhere on the interweb that reports on current space weather impacts on GPS?

Grouse

Unknown to the general public, there are specific circumstances when the military does alter GPS. Probably not what your experiencing.

During the campaign when trump flew into wi, I saw my gps jump about a mile, then fluctuate.

While I was reading this thread I started to wonder if my Iphone really had GPS and I guess it has it but will choose the fastest method for finding my location. It will use WiFi or cell towers first and if that’s not working it will use GPS. Still wonder why we don’t see what Satellites it is picking up. The type of GPS is A-GPS and it dose not have WAAS.

Download a GPS test app. There you can see which satellites you are connected to and what your accuracy is.

Some apps also allow you to clear the AGPS Cache in your phone and reload current data which may help.

This is the one I use for Android.

https://play.google.com/store/apps/details?id=com.chartcross.gpstest

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If you turn the app on and walk around going inside and outside, under trees, etc it is almost real-time updates showing what will affect your accuracy. It will give you a good idea of what to look out for if you need accuracy. Even a window can affect location significantly.

Randy Wieland wrote:

Unknown to the general public, there are specific circumstances when the military does alter GPS. Probably not what your experiencing.

During the campaign when trump flew into wi, I saw my gps jump about a mile, then fluctuate.

The current chatter in the industry is the widespread inaccuracies are due to a Sony datafile and the year 2020 actually having 53 weeks.

Although they claim “selective availability” of more precise GPS signal ended in 2000, the military can certainly alter the accuracy of GPS satillites. They even have ability to affect/jam via false signals GPS in select areas.

That is the basia of another theory: it may have something to do with the threats of an attack by Iran as there are reports of inaccuracy on devices not using the Sony chipset.

Interesting Badgerbacker! I thought about the Iran situation too. My Lowrance gps has waas, and it’s very close to my Navionics. Both bad.

So I wasn’t the only one! Saturday I tried a spot and GPS said I was in 15ft off a break. Drilled a hole and had a heart attack when my flasher read 5ft. I thought my flasher was broke. I was about 100 yds off.

About the same for me Joe. 100 yds!

Haha I fiddled with my flasher for about 10 min trying to figure out what was wrong. Then I decided to keep moving towards where the deeper water was. I almost threw my flasher across the ice

USA GPS signals are controlled AND turned off from time to time by the US government. I occasionally am made aware of GPS “testing” and outages. It’s almost always in the SW USA. GPS drops offline in the jet completely. We utilize many sources for navigation, but GPS is generally the most accurate. Check your units and see if you can verify how many satellites your unit “sees.” You may be able to use Galileo (European based) and/or GLONASS (Russian based). You may also be able to use WAAS (Wide Area Augmentation Service) for increased accuracy. You may also have an option for differential GPS. The more satellites your unit uses, the better your accuracy. Keep in mind, if you stop, or are barely creeping along, your accuracy will immediately be reduced. Read your manuals and see what your particular units can utilize. Generally speaking, more satellites is better accuracy.

Good luck!

Back on today.

Now if I only could fish

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