Case measures 40mm lug to lug x 28mm non inclusive of the Crown using Calipers. White Dial shows applied Gilt Arabic numerals, Bulova signature and tracks are printed in Black with the Outer register Calibrated at 5 Second intervals. Hour and Minute Hands are Gilt Modern style and a Gilt Modern Seconds Hand appears on a sub Dial fully obscuring the 6. Flyback Center Seconds Hand is actuated at the Crown. * Caseback is Gold and stamped as shown. Leather Strap is NOS JB Champion. Horseshoe Gold Buckle is signed Bulova. WWII'ish miniature Chronograph often called a 'One button' or 'Single button Chronograph. Like many of the Ladies in My Life this one also has issues. The Watch Sets, Winds and Runs but after comparing notes with Jay at www.vintagebulova.com it seems someone left a piece of the Start / Stop function of the Chronograph pusher off. (see the screw head near the stem)
* Currently the Chronograph runs full time with no way of stopping it.





admin,
The information was sourced from a conversation between Dr Roland Ranfft and Members of the NAWCC which occured in 2006.
http://mb.nawcc.org/showthread.php?13707-Bulova-10AH-Miniature-Chronogr…
Dr Ranffts' source of information on the Bulova 10 AH is Book entitled 'Chronographen' by Lang/Meis.
* An excellent shot of the 1942 Datecode which looks like an Anchor.
IMO
The ID of this Model was previously changed from generic 'CHRONOGRAPH' to 'MEDICO'.
Although similar there are differences between the 'MEDICO' as advertised and the subject single button Chronograph.
Notable differences are the Case, the Case lugs, the Dial and the Chronograph actuator button, the subject Watch is not the 'MEDICO'.
'CHRONOGRAPH'
October 1947 ad used from the other watch database "Medico record" here: http://www.mybulova.com/watches/1942-medico-5437
The lugs in both these watch records may be different than the lugs in the ad above.
I would suggest the Watch Dated 1946 shown below is possibly the 'MEDICO'
http://www.mybulova.com/watches/1946-chronograph-5195
* Note: the Case lugs are shorter with the Case measuring 33.5mm lug to lug vs 40mm for the 1942 subject, the Chrono actuator also differs.
The Watch depicted in the 1947 ad bears no resemblence to the subject other than it has both sweep center Seconds and a sub Dial.