Description: This ca. 1972 model is one of Rado's many electronic/electric models that bridged the gap between the standard automatic & mechanical movements of pre-1970 and the quartz movements that because prevalent by the mid-1970s. This watch features a tuning-fork movement made by ESA with technology licensed from Bulova, creators of the original tuning-fork wristwatch: the Accutron. This example has Rado's trademark scratch-proof tungsten-carbide case. It is beveled along the sides and is faceted across the top with five planes that are matched by similar facets in the sapphire crystal. The dial of this watch features an unusual mesh or cross-hatched tecture that reflects light in a way that mimics mother-of-pearl. Typical of many Electrosonic models, this watch has U-shaped hour markers that combine with printed hash marks to approximate the shape of a tuning fork.

Not present on this series is the rotating anchor logo previously seen on Rado watches with automatic winding and many of those powered by electro-mechanical movements. There is, however, a singular logo only found on the Electrosonic models.

The case front shows no wear, though the back has some minor marks. The movement is keeping accurate time and actually hums nicely. Service history is unknown, but the movement is clean; date functions properly at midnight.

The original SK bracelet with signed Rado clasp is present on this watch.

Photos: Click for larger images

Some similar models as this were marked "Diastar" on the dial, as shown in this 1970s advertisement.

This watch has been sold.

Text and images © C. Bradley Jacobs, WatchCarefully.com