chmandaue
102
Independently Adjustable Hour Hand (IAHH)
A watch with independently adjustable hour hand or 'IAHH' refers to the ability to move the indicated time on a watch forwards or backwards by whole hours1 without disturbing timekeeping. Every 'traveler' GMT watch has an IAHH, but there are 3-hand watches with IAHH as well.
Submitting my new article on this topic with:
a) the 3 reasons for IAHH
b) comparison of pusher vs. crown adjustment
c) electronic and mechanical implementations
d) 2 recent patents in IAHH adjustment feel
e) the complications of combining IAHH with simple, annual, and perpetual calendars
f) aside on the GMT hand stack

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