At a time when quartz meant LCD displays and tech influenced architecture, Seiko took a step back in order to bring watch design forward. Introduced in 1983, the 7A28 was the worlds first analog quartz chronograph, and to say they got it right is an understatement. Solid construction, “fly by wire” circuitry, and a hefty 15 jewels make for a finely tuned machine that can be adjusted to dial in performance, and allows for the replacement of worn components. The same can’t be said for most of the quartz movements seen even today. Two years later, in 1984, the 7A38 and 7A48 were introduced. The ‘38 added a day and date feature along with a whole host of new design layouts, but the ‘48 delivered a complication that at the time was typically associated with high end Swiss mechanicals: the moon-phase. This example from May of ‘84 is yet another opportunity to marvel at the genius and efficiency of Seiko engineering. I still remember the first 7A48 I serviced, and beforehand, trying to imagine the mechanics of certain functions before I dove in. Though the driving mechanism for the date and moon-phase was pretty standard fare, i was more than curious to see how the setting function operated. With the crown in the second position, counter-clockwise rotation advances the moon-phase disc, and clockwise, the date. That may sound simple enough, but try to imagine a simple machine that can rotate a pair of stacked wheels in the same direction independently just by changing the directional rotation of the handle. In addition, you have less than two millimeters of height to accommodate it. As it turns out, the date wheel, and the moon-phase wheel share a single operating lever that shifts linearly to pull from one side, and push from the other dependent on which direction the wheel it’s attached to is rotated. Perhaps I’ll share a video at some point to better explain, but it is no doubt an impressive feat of engineering. It certainly made me smile. The visual details are equally impressive. In addition to the three prior sub registers, a nicely balanced fourth sits at 12, with a cutaway window that reveals the moon-phase disc in navy and gold. The date is denoted by a matte finished pointer with a crescent tipped tail. The enamel white dial is finished in black print with gold stud markers, and is framed by a deep set chapter with Roman numeral hours. The plating on the rounded bezel does show wear through on the corner, but has overall aged well. The case is a hooded tonneau with a brushed finish and is attached to the original two-toned “H” link bracelet with yellow bar hinges. It’s completely original aside from a replacement mineral crystal, and post service is keeping perfect time, and all functions are operating correctly. Great versatility and timeless styling make this one an easy addition to any rotation. 

Original Seiko Tapered “H” Link Two-Tone Bracelet

Serviced- 1/26

Diameter- 39.5mm

Lugs- 20mm