Seiko Grand Quartz 9943-8020 Twin Quartz 1978

JimInOz · Dec 12, 2025

Couldn't resist it last night, managed to snag it despite competition.

Seiko 9943-8020 “Grand Quartz”, August 1978.
Diamond dust dial, 7J Twin Quartz, HAQ 10 seconds +- per year.

Arriving early next week.

Walrus · Dec 12, 2025

That is cool as hec. I think I saw only one before I have no idea if they are “rare” I just personally seldom see that dial type nice score.

bralofsky · Dec 13, 2025

Congratulations in advance.

JimInOz · Dec 13, 2025

This is what helped me decide.

(Seller's video).

GarethS · Dec 14, 2025

Now that is one sharp piece. Gorgeous.

Larry S · Dec 14, 2025

Safe queen? Wow! I need a Seiko in my stable.

Leeroy · Jan 5, 2026

I've been dancing around the 9942/9943 for a while and this thread gave me the arse kick I needed to put a decent bid in.

As a time keeping instrument the 45 year old 9943 is still up there with the big boys and as a piece of wrist jewellery it doesn't disappoint. Cheers @JimInOz hope yours is as nice as it looks in the video.

vienna · Jun 7, 2026

I just finished assembling this nice 4843-8041 after a complete strip down, cleaning, oiling and adjusting on a Seiko QT-99. Temperature compensated movement from 1976, now running on +0,02 sec/day.

The 4843 was the predecessor of the 99-series twin quartz movements from Seiko.

SOG53 · Jun 9, 2026

4842-8041 that I regrettably sold for a song
I liked the big chunky case
These were not quite the timekeeping superstars that the twin Quartz models, but not far off.

One of many victims of my misguided “too many watch” sell off of rather nice group of Seiko quartz…..😢

watchmann44232 · Jun 10, 2026

Another one from -76 (4842-8041/8030T, with serial only 78 a part) says hi + a 1976 catalog photo. These early Seiko Quartzes (Type II, Lord, King, Grand and Superior) in all their variety are just really nice and (still?) often times good value.

I had never seen those diamond dust dials except in the photos. Thank You for that video - it is very, very nice.

vienna · Jun 16, 2026

To complete the trio and for posterity here my 4840-8041, the no date version.
Just finished servicing her, these dials are rather rare birds and give the watch a very clean and tidy look in my opinion. Also, the dial has a very fine kind of sandpaper structure.

Kind regards Max