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How can a watch also be a compass?

Engee
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On another thread here @Iceter mentioned the Seiko Alipinist https://www.seikowatches.com/uk-en/products/prospex/spb119j1 which think is rather interesting. But the obvious question came to mind. How does that work? A compass is basically a magnet that interacts with the earth's magnetism, but a watch hates a magnet. How can it be possible to make a watch with magnet built in?

Clearly showing my utterly unscientific mind or knowledge, I'd love someone to explain this to me.
 
MtnMarine
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Engee Engee
On another thread here @Iceter mentioned the Seiko Alipinist https://www.seikowatches.com/uk-en/products/prospex/spb119j1 which think is rather interesting. But the obvious question came to mind. How does that work? A compass is basically a magnet that interacts with the earth's magnetism, but a watch hates a magnet. How can it be possible to make a watch with magnet built in?

Clearly showing my utterly unscientific mind or knowledge, I'd love someone to explain this to me.

To use your watch as an approximate compass outside of the tropics in the northern hemisphere, hold the watchhorizontal and point the hour hand at the sun. Half way between that point and the twelve o'clock mark on your watch points to the south.

copied from geographyfieldwork.com

no magnets involved, most movements aren’t anti magnetic. At least most vintage ones aren’t.
 
Engee
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MtnMarine MtnMarine
To use your watch as an approximate compass outside of the tropics in the northern hemisphere, hold the watchhorizontal and point the hour hand at the sun. Half way between that point and the twelve o'clock mark on your watch points to the south.

copied from geographyfieldwork.com

no magnets involved, most movements aren’t anti magnetic. At least most vintage ones aren’t.
Right, but this watch has a rotating compass built in. If I know where the sun is and I know what time of day it is I can get an approximation of the direction I'm facing without pointing my watch anywhere. Sun rises in the east. If it's morning and the sun is up I know where north is.
 
Ascalon
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Engee Engee
Right, but this watch has a rotating compass built in. If I know where the sun is and I know what time of day it is I can get an approximation of the direction I'm facing without pointing my watch anywhere. Sun rises in the east. If it's morning and the sun is up I know where north is.
I think the compass ring is there and rotatable to facilitate this method of reading.

You still need to orient the watch correctly, as per above, to get North. Then turn the inner ring to align with the hand and then you can read accurately the major directions from there.
 
MtnMarine
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Engee Engee
Right, but this watch has a rotating compass built in. If I know where the sun is and I know what time of day it is I can get an approximation of the direction I'm facing without pointing my watch anywhere. Sun rises in the east. If it's morning and the sun is up I know where north is.

I didn’t realize that.... hopefully another more educated member can help you. My mistake.
 
Engee
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Ascalon Ascalon
I think the compass ring is there and rotatable to facilitate this method of reading.

You still need to orient the watch correctly, as per above, to get North. Then turn the inner ring to align with the hand and then you can read accurately the major directions from there.
Aha, I see, so rotatable but not magnetic - thank you. That makes sense, although it also makes it nothing like as interesting as a tool.
 
Engee
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MtnMarine MtnMarine
I didn’t realize that.... hopefully another more educated member can help you. My mistake.
No, it looks like you were more right than me!
 
redpcar
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Tissot T Touch also comes to mind. Pretty cool how the hands line up and act like a compass.

upload_2020-11-19_9-37-25.png
 
Vitezi
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Engee Engee
I'd love someone to explain this to me
Find-direction-with-watch.jpg
 
Pun
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How to calculate south if it's 7 am? Just little dumb to understand...
 
MtnMarine
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Pun Pun
How to calculate south if it's 7 am? Just little dumb to understand...

just sleep a few more hours and then check....
 
MtnMarine
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redpcar redpcar
Tissot T Touch also comes to mind. Pretty cool how the hands line up and act like a compass.

upload_2020-11-19_9-37-25.png

I happened to have an older model one of these in my watch bin. I may have to get it out and see if I get it back to working. Thanks!!
 
Vitezi
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Pun Pun
How to calculate south if it's 7 am? Just little dumb to understand...
If you have access to @Mad Dog 's Boy Scout manual (from 1910), the explanation is here:
STEM-Scouting-in-1910.jpg
 
Iceter
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The Alpinist “compass” is just a rotating ring, operated by the second crown.
 
SpeedyPhill
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Knowing the exact time with Your wristwatch and seeing the Sun is enough...
At noon Sun is in the South & moves on to the right into WEST ( noon = North for the Southern hemisphere moving on to the left into WEST )
 
STANDY
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SpeedyPhill SpeedyPhill
Knowing the exact time with Your wristwatch and seeing the Sun is enough...
At noon Sun is in the South & moves on to the right into WEST ( noon = North for the Southern hemisphere moving on to the left into WEST )

Umm yeah not really good if you on the ocean without land in sight.
East west is sort of helpful but not all you need.

Noon anywhere in the world makes north every way you look...😗 (think about it)
 
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