| Manufacturer: | Ebauches S.A (Under Lic. to Bulova) |
| Dimensions: | 30.4mm x 7.95mm |
| Commencement of Manufacture: | 1972 |
| Tuning Fork Frequency: | 300 Hz |
| Index Wheel: | 300 teeth |
| Derived Calibres | Derivative of the Esa 9162/4 |
Although this watch is a derivative of the Esa 9162, its uniqueness justifies a separate page from its base calibre. The picture above is the movement in its Omega Speedsonic form, though it was used in Longines Ultronic and Certina chronographs as well, and possibly others.
The chronograph mechanism is in modular form (see esa 9162/4), and mounts on the dial side of the movement. It contains the gear train for the chrono mechanism, and a train for driving the hands and date mechanism. Both trains are driven by the intermediate wheel, which passes through the pillar plate and has its upper bearing in the chrono module. See drawings below.
The functional specifications of this movement are the same as for the Esa 9162. It is a complex watch in its construction and operation. Definitely one only for the very experienced repairman to dabble with.
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1) Chronograph Module 2) Mechanism Module (pillar plate) 3) Oscillator Module |
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4) Intermediate Wheel 5) Chronograph Driving Wheel 7) Friction Wheel (hands) 8) Hand-setting Wheel |
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4) Intermediate Wheel 5) Chronograph Driving Wheel 6) Time Display Wheel Train 7) Hand-Setting Wheel 9) Index Wheel |