npub1kpwlxpzkxfmuxjmzc2wp3rf9vjg0sgydmlhsnrgqr3maf59h86qqdxxzz4 (npub1kpw…xzz4)
Mechanical compasses of that sort are more complicated, at least because you need a vertical reference and a gimbal with 2 degrees of freedom.
Also, that's not very accurate if you don't know your longitude: the isolines of vertical strength are amusingly curvy: https://upload.wikimedia.org/wikipedia/commons/4/4c/World_Magnetic_Inclination_2020.pdf
BTW I wonder how many sports trackers use the magnetic field to simplify their motion tracking, and then work very differently sufficiently far north or sufficiently close to the equator. (E.g. for breaststroke in swimming pools oriented east-west in Switzerland keeping a running average of the magnetic field direction at wrist is a more reliable way of counting lengths than what Garmin was doing up until something like 1-2 years ago)
npub1v6…s9004
2024-02-09 02:29:36
in reply to nevent1q…t05y
Author Public Key
npub1v67gmn7f4vlg3fcrk8up3p08rkmqqaxmw0he3hf9f8h09jre332qds9004Seen on
wss://relay.nostr.bandPublished at
2024-02-09 02:29:36Event JSON
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