Author Topic: Compasses and Magnets  (Read 816 times)

happyhiker

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Compasses and Magnets
« on: 07:39:51, 16/02/18 »
interesting article. Evidently some garment manufacturers are starting to use magnets instead of Velcro/poppers and the warning, which also applies to mobile phones, is about the danger of compass polarity being reversed if it is in close proximity to these items (presumably for any length of time). Has anyone experienced a reversal of polarity?
https://www.grough.co.uk/magazine/2018/02/14/flip-experts-warn-new-clothing-trend-could-be-fatal-attraction-for-your-compassion


Apologies. Just noticed similar item under "Gear". Ignore my post - don't know how to delete.
« Last Edit: 07:45:00, 16/02/18 by happyhiker »

fernman

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Re: Compasses and Magnets
« Reply #1 on: 10:13:04, 16/02/18 »
When it happened to me, for I used to put both phone and compass together in the lid pocket of my daysack, the needle pointed about 20 degrees west of north when compared with the replacement I had to buy.

I could tell the old one was faulty during my walk because there were distinct landmarks around me and I could see the hill whose base I was aiming for, but my compass was pointing me to one side of it.


I don't think there is a way to delete a post. On the rare occasions I've needed to, I just deleted the text and wrote two or three words to say so.

gunwharfman

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Re: Compasses and Magnets
« Reply #2 on: 11:46:58, 16/02/18 »
I have a compass but haver used it. I used my phone compass once in 2015 in thick fog.

Deolman

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Re: Compasses and Magnets
« Reply #3 on: 15:14:07, 16/02/18 »
I had a compass with reversed polarity some years ago.  I corrected it by using a strong magnet and stroking along the length of the needle - worked ok after that.

roughyed

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Re: Compasses and Magnets
« Reply #4 on: 15:13:35, 19/02/18 »
A good reason to stick to a GPS...

(ducks for cover!)

Deolman

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Re: Compasses and Magnets
« Reply #5 on: 15:19:04, 19/02/18 »
Not really.  If a compass goes reverse polarity it will still work, just remember which end is pointing North.  If a GPS fails while your out walking not much you can do unless you intend taking an electronics technician out with you each time you go walking

roughyed

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Re: Compasses and Magnets
« Reply #6 on: 15:23:16, 19/02/18 »
Not really.  If a compass goes reverse polarity it will still work, just remember which end is pointing North.  If a GPS fails while your out walking not much you can do unless you intend taking an electronics technician out with you each time you go walking


How do you know its reversed polarity in a white out?  In the dark? 

sussamb

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Re: Compasses and Magnets
« Reply #7 on: 15:35:16, 19/02/18 »
A good reason to stick to a GPS...

Not really.  If a compass goes reverse polarity it will still work, just remember which end is pointing North.  If a GPS fails while your out walking not much you can do unless you intend taking an electronics technician out with you each time you go walking

As I and others have constantly said if you use a GPS you need a back up, mine happens to be a phone, but at least I always know when the GPS is working (and mine has never failed) the compass is accurate  ;)
Where there's a will ...

roughyed

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Re: Compasses and Magnets
« Reply #8 on: 16:05:16, 19/02/18 »
As I and others have constantly said if you use a GPS you need a back up, mine happens to be a phone, but at least I always know when the GPS is working (and mine has never failed) the compass is accurate  ;)


And I may of been being a tad tongue in cheek  8) :P

Deolman

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Re: Compasses and Magnets
« Reply #9 on: 17:38:49, 19/02/18 »

How do you know its reversed polarity in a white out?  In the dark?


There's a modern invention that's taken over from the candle-it's called a torch😃

roughyed

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Re: Compasses and Magnets
« Reply #10 on: 08:32:58, 20/02/18 »

There's a modern invention that's taken over from the candle-it's called a torch😃
How does a torch tell you if the compass is pointing in the right direction?  Without a known landmark or the sun, you have no idea if the compass is right or wrong. 

Deolman

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Re: Compasses and Magnets
« Reply #11 on: 09:15:53, 20/02/18 »
Navigation is more than just looking at a compass.  If reading your map correctly you should have a good idea of the direction you need to take - if the compass has reversed polarity you are now walking in the complete opposite direction and  that should become obvious fairly quickly.  This was how I realised that my compass had reversed its polarity though admittedly not at night when navigation can be a lot trickier and requires some form of illumination to look at your compass, your map, and your immediate surroundings. (Hence my tongue in cheek comment!) I know my navigation leaves a bit to be desired so like others on this post I also carry a GPS.

sussamb

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Re: Compasses and Magnets
« Reply #12 on: 11:03:45, 20/02/18 »
When I did my Silver NNAS exam the examiner handed me his compass and asked me to set a bearing.  Thankfully I realised quickly he'd given me one, deliberately, that was 180 degrees out  :)
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Rather be walking

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Re: Compasses and Magnets
« Reply #13 on: 12:10:26, 20/02/18 »
You think you have problems now, wait until this happens.
https://en.wikipedia.org/wiki/Geomagnetic_reversal

Jon.
LDP Done:SWCP,SDW,IOWCP,HadriansWallPath,NDW,ClarendonWay,HangersWay,C2C,CaminoDeSantiago.

sussamb

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Re: Compasses and Magnets
« Reply #14 on: 12:22:55, 20/02/18 »
Doubt if I'll live long enough to see one  ;D
Where there's a will ...