# 2 (new to me) Cosmotrons



## Mr Levity (Feb 24, 2013)

I've developed a taste for electronic watches recently and thought I'd share two of them with you. Lots of info about them on Sweephand's excellent blog (very helpful, you learn something new every day in this hobby  ) so I won't get technical.

Both were bought from the same Evilbay seller.

First up is a white dialed 7804A from November '73. 36000 BPH 8J movement. Kanji day wheel and date. Timegrapher says the amplitude and beat rate are not very good (no idea of the lift angle of either of them, which could throw things out), but it's been OK since I've had it (worn three times for several hours). It's gained 45 seconds in the three months that I've had it.




























Original bracelet, not easy to photograph, and the logo is actually quite clear.










Next is the 7803 powered "special". Monocoque case, so not sure of jewel count or if it has a suffix, but still 36000BPH. Again the Timegrapher says the amplitude and beat rate are way out, but it's only gained 2 seconds in the week I've had it.

Green faceted dial with Kanji day wheel and date.



















The small screw is removable and reveals the adjuster screw (though again, for some reason, mine doesn't. Just a blank piece of metal).

Again, original bracelet, but this one has an extender. I've just about managed to get it to fit my skinny wrist as the extender isn't removable without making the bracelet very sloppy.










The "Special" refers to the button @8 that resets the seconds hand to zero. It should also (mine doesn't :sadwalk: ) reset the minute and hour hands to 12 when within 2 minutes to. The seconds hand reset works in the same way as a flyback chrono (such as the Seiko 701X), i.e. the button is pressed while the movement is running and the seconds hand returns to 12 o'clock. There is a video of how this works on Stephen's blog. https://sweep-hand.org/the-x8-cosmotron/

The seller was very honest and disclosed the two major scratches to the crystal, but as you can see, they aren't visible unless viewed in a certain light.










I think a few more electronics may be on the radar.


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## Guest (Jun 5, 2016)

beautiful and quality, not the most common either and values are increasing quite fast..........get buying while you can :yes:


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## gimli (Mar 24, 2016)

Love the movements...


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## davidcxn (Nov 4, 2010)

Two interesting and smart looking watches that have a place in the history of watchmaking design and technology. :thumbsup:


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## bridgeman (Dec 9, 2008)

Mine is awaiting repatriation from the electric watches hospital and is due back this week. The upside downside inversion to change day and date is probably unique


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