BULOVA 224 ACCUQUARTZ 1972
The 224 Accuquartz by Bulova is their first inhouse "quartz" watch based on their last tuning fork 218 movement. After the initial limited Beta21-Accuquartz batch, that sold only in 1971 in large solid 18K gold cases (100g), Bulova quit cooperation with CEH and decided to continue on their own in the mass-market Quartz race. The race in the field of research was pretty much lost and legend has it that Bulova's management didn't even consider Quartz to be a threat (like most traditional manufacturers in those days that went bankrupt). So in order to cut costs and speed up the invention process they revitalized the old 218 tuning fork calibre and added a few minor modifications with small chip and 32.768Hz quartz on top. Read more on the ultimate Accutron source managed by Rob Berkavicius from Oz/Thailand.
This 224 Accuquartz appeared in 1972 (N2 code) and with dozens of designs was proudly marketed as Quartz until approx. 1976. It was also made in high-grade for Universal Geneve as "UniQuartz". The concept is simple but the tuning fork is no longer the source of stable frequency. It is only used as a motor that moves the hands (by means of a pawl and index finger) but additionally it is controlled by the electronic circuit which serves as the source of frequency. This idea is practically a copy of the Beta21 but also similar to the Ultra-Quartz with one-way communication to the motor. Timekeeping can be adjusted the same way with small screws on the circuit which activate corresponding resistors (do not manipulate unless timekeeping is completely out of line). NOTE! Accuquartz models from 1977 feature standard Swiss quartz 242 or ESA 9362.
Keywords: bulova accuquartz, 224
Market value: 50-350$ (steel, goldfilled or solid gold,model, condition)
early Beta21 Accuquartz are impossible to find and might cost 2500-5000$