How-to: use the slide-rule

Robert-Jan Broer
May 04, 2007
How-to: use the slide-rule

Probably one of the most sought-after Breitling models is the Navitimer ref.806. However, not everyone (or every owner) knows how to use all the information on the dial in combination with the slide rule. Bill Sohne, a well known collector who’s active on the internet for years now, and Chuck Maddox (the ?ɬºber Chronograph-meister) put the original manual online of the vintage Breitling 806 Navitimer APOA.

It describes perfectly how to perform calculation with this watch, using the slide rule. Click here for the online manual.
Scan of the manual below by Bill Sohne and published by Chuck Maddox.


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Robert-Jan Broer
About the author

Robert-Jan Broer

Ever since he was a young child, Robert-Jan was drawn to watches, even though it were digital Casio and quartz Swatch models at the time. In the mid-1990s, his interest increased when he started to read about mechanical watches in... read more

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