Hoorah, hooray, haloo, halay! External regulators!
Click pic to go to ThePuristS JeanRichard thread.
I've been wondering why no-one has done this on a modern watch for as long as I can remember. Kind of reminds me of the fine Advance/Retard thumbwheel on (Lucas?) distributors of old (ask your dad)...........
Click pic to go to IanS's report on the Urwerk 103.03.
Thanks to John A. Frye for pointing it out on the Urwerk
Wow, need to sit down now.