Ricoh Riquartz 1970s 811 module LCD watch

One of the problems of buying old watches is that sometimes, no matter what you do, the watch won't work. Unfortunately, today's watch is one of those, even though it looks completely unworn!

The watch is by the Japanese electronic and image company Ricoh. They made the Riquartz watches in the 70s and 80s, and this seems to be a sideline from their main office and camera businesses.

This model has a Riquartz 811 module compared to the 812 module of my previous Riquartz post. Judging by the printing on the inside of the back, it was made in June 1976. The module is one of the neatest and cleanest I've seen in a watch with virtually no circuitry visible.

The display is a 3 1/2 digit LCD with a pm marker. I don't know what modes it has, but judging by the age and lack of buttons (1 plus an inset setting button), I'd guess only time, date and seconds displays were possible.

Since the last post, it seems that the 6 digit number on the back is the model number, and there is no serial number. This watch's model number is 811003 and this is shown on the watch back and the tag (which makes me see it doesn't include the serial number).

The tag also shows it cost 27,800 yen which was very expensive at the time.