simone wrote:yes it's possible. Maybe this is an earlier version of the "Pulsar" Lcd module...it has no light.
There was also a Ricoh version of this with a backlight, think it was the 812 - same display but quite different construction inside, two batteries, big plastic carrier and impossible to take apart...Your much easier to disassemble 811 is circa 1976 (I had a clearly dated version from July 1976)
(1970s Riquartz watches have production year and month stamped in ink inside the back cover - months as 1 to 9 then X,Y,Z - but ink gets washed off quite often...)
767Geoff wrote:Hamilton (USA) and Ricoh had a trade agreement. Many later Hamilton movements (just prior to closing shop in the USA) were made by Ricoh, including both mechanical and digital”.
..and Electrics - the Hamilton-Ricoh electrics that were also exported to become the Standard Time 505 Electrics.
On the Pulsar thing, Ricoh also produced LED watches with Pulsar-esque movements. Similar internals to a miniature P4, known by them as the Ricoh 860. I think I read somewhere that Pulsar P4 modules were made entirely, or in part by Sanyo in Japan too (circa 1975)
There were also Riquartz 870 LED watches with the four button Sanyo modules as also used by Citizen in their LED watches (circa 1975).
AFAIK, the earliest LED from a japanese manufacturer was the Riquartz 910 which was just an early Hughes 29mm dot (circa 1973) - both Seiko and Citizen had already moved on to FE LCD by then.
Seems like Ricoh had a knack of piling into the 'last big thing' just as everyone else was moving on to the 'next big thing'.