Bulova Precisionist 'Langford'

cal. P102.12

Factory Spec. 10 SPY

Thermoinsensitive: High Frequency (262 kHz) + Tri-pronged Resonator with Flexural and Torsional Modes

This watch uses a unique tri-pronged quartz oscillator running at 262 kHz. It is said to combine both torsional and flexural modes, thereby reducing the influence of temperature. This is very similar to the approach taken by Seiko with their Twin Mode Quartz and, coincidentally, patents on the technology expired just a few years before Bulova released this 'ground-breaking' watch. The old Seiko didn't use a tri-pronged crystal (although the patent for that expired at about the same time), but it did use a special cut of crystal to combine two resonance modes. It was also supposed that the Seiko used a high frequency oscillator, but precious few details have emerged about this old movement and I haven't been able to test the frequency of the example that I have got.

The Precisionist has a few points of interest:

1. Originally claimed to be accurate to 10 SPY, though this claim is now very hard to find in Bulova's current marketing materials
2. The second hand ticks 16 times per second. Not as smooth as a tuning fork or a Beta 21 or a Seiko 5S21 or a Spring Drive, but smoother than any mechanical watch, for sure!
3. The stated battery life is just one year

Some details for this watch may be missing as it has not yet completed comprehensive testing.