The Pioneer Mk I is a replica of the first precision chronograph produced by Hanhart in 1938. All of the chronograph functions on this unconventional mono-pusher model – start, stop and zero setting – are performed by a single button and always strictly follow each other. Unlike its two-button equivalent, the seconds hand on this chronograph cannot be restarted from the point at which it is stopped; the next press of the button invariably returns the spring to the original starting point. This meant that the calibre used for the Mk I also had to be redesigned slightly. The crank which sits directly beneath the button that would normally be positioned at 4 o’clock has no function. A large shift lever is therefore responsible for the third strike on the chronograph cam. This cam has also been modified by Hanhart so that it has an additional tooth on its lowest level. The shift lever can thus control not two, but three positions.
Movement: HAN3601 modified automatic chronograph movement (bicompax), based on the Valjoux 7753 calibre, with increased crown-to-button spacing and single-button conversion; 28,800 vibrations per hour, 4 Hz; 27 jewels; power reserve of min. 42 hours
Functions: Small seconds at 9 o’clock, 30-minutes counter at 3 o‘clock
Case: Stainless steel; red button; fluted, bidirectional rotating bezel with red marking; convex, internally anti-reflective sapphire glass; screwed-down case back; diameter 40 mm, height 15 mm; water-resistant to 10 bar/100 m
Dial: Black; Super-LumiNova®-coated, luminous numerals and hands