A few times in my life, I ran into situations where I was in areas that had a high iron ore content, driving my compass nuts. The first time was pretty freaky, because I had no idea what was happening, but my compass started pointing North to the East, then the South, then spinning in circles. Anyhow, my cell phone (an old Apple 4, I think) has a compass app, that does not rely on Internet service, as I don't have a data plan and it works in areas with no cell phone service. Does anyone know if that app is actually a compass, or does it work off GPS sats? DO you know if it would be immune to magnetic interference?
Compass question
- Thread starter Papaclaude
- Start date
holzmeister
Regular
- Location
- Neumarkt Ontario
GPS my friend and pretty accurate s well
Depends on the model of phone.
My cheap Samsung does not have a physical. My kids expensive phone does.
My GPS spoftware approximates from inertial and satellite readings. His gives a magnetically accurate reading on it's own.
My cheap Samsung does not have a physical. My kids expensive phone does.
My GPS spoftware approximates from inertial and satellite readings. His gives a magnetically accurate reading on it's own.
Not sure id actually trust a cell compass for any sort of actual navigation... cant imagine what trying to swing it would end up like (you need to swing a compass to develop your deviation table which will help you convert from compass to magnetic - and you need variance to go from magnetic to true). And yeah, i cant imagine how much he ore would mess with it. Fortunately for me, my experience is entirely marine, we have other challenges to manage, like the lead in my butt, the metal of the hull, the high power radar above the compass,the list goes on.
I've never had a situation where my compass went all nutty like that, but I have had it thrown off before.
Back in my surveying days we were retracing old property lines that hadn't been marked or anything for 70+ years and I was following along from my last known point, looking for old blazed trees and recording it all with out GPS unit. After I found enough old stuff to make a straight line I followed it, and my compass damn near exactly as the old plan said it should be.
When we got back and mapped the gps data out we had a big bump in our line where we came off, walked parallel to it a bit, then back onto our line, which raised some eyebrows about how closely we were really paying attention on that day. We went back and walked it a second time though and again, the compass pointed right in the direction we walked the whole way.
The original surveys in the area were done with a staff compass, so they obviously had the same thing happen to them the first time, but what was crazy to me was that even after the compass led us off the line, that it brought us right back perfectly on to it. I couldn't have done that on purpose if I tried, but the weirdness of the rock in the area did it perfectly.
Not to get off topic but... I have no idea how the phone aps work
Back in my surveying days we were retracing old property lines that hadn't been marked or anything for 70+ years and I was following along from my last known point, looking for old blazed trees and recording it all with out GPS unit. After I found enough old stuff to make a straight line I followed it, and my compass damn near exactly as the old plan said it should be.
When we got back and mapped the gps data out we had a big bump in our line where we came off, walked parallel to it a bit, then back onto our line, which raised some eyebrows about how closely we were really paying attention on that day. We went back and walked it a second time though and again, the compass pointed right in the direction we walked the whole way.
The original surveys in the area were done with a staff compass, so they obviously had the same thing happen to them the first time, but what was crazy to me was that even after the compass led us off the line, that it brought us right back perfectly on to it. I couldn't have done that on purpose if I tried, but the weirdness of the rock in the area did it perfectly.
Not to get off topic but... I have no idea how the phone aps work
- Location
- Saskatchewan
I've always heard stories about ore bodies causing magnetic interference, never believed it. After reading up on it, I now realize it can happen. I still think a more likely cause of problems is holding a rifle too close, or a belt buckle, etc.
In those cases, that was not the cause, as I knew about the rifle barrel issue, and don't normally wear a belt. I've had it happen twice, once where there was enough ore that there was a mine nearby. The second case, I don't know what the grade of ore was.
Trimmer 905
CGN Ultra frequent flyer
You weren't hunting around the Bancroft area,were you? It happens around there all the time from the iron ore and uranium deposits. A hunter really needs to know where they are at all times.
No - once was near Kenora (Nestor Falls IIRC), the other times were between Kirkland Lake and Larder Lake, in NE Ontario.
A friend was hunting South of North Bay and was having a lousy time getting his GPS to accurately give a consistent reading. He tried 3-4 X to recalibrate the compass but is "failed" each time. Batteries were new but his GPS kept shifting it's compass direction. Standing still, it kept jumping directions showing N then W then N then E. It refused to give a stable reading. It took several more tries to recalibrate but finally succeeded. Not sure what was going on but others have had similar experiences there.
