This is a watch I originally bought to repair and sell on my www.time-tees.com but once it arrived I thought it was far too interesting to pass on. Never seen such a bright dial with such texture and then to then fit it under a facet crystal makes for a very interesting look.
This one is from 1974 and housing the 7803 version of the Cosmotron movement. These movements are an electronic balance movement. On the market at the same time as the quartz you can see how technology was being pushed in horology at the time. With these type of movements you get a second hand sweep, a fully mechanical watch but its powered by a battery instead of a mainspring.
How it works is that you have a small circuit board with a transistor and a coil attached that is flat circular shape. This coil then fits inside the balance wheel, this balance wheel has two wheels on it and a hairpsring on the top. The bottom disc has two magnets on it along with a small magnet on the mainplate! Magents in a watch!! so repairers please note, DO NOT demagnetise this movement as part of your service procedure!
The transistor creates a pulse to the coil which creates a magnetic field that is polar opposite to the magnets on the coil. This makes the balance spin and thus transfers this movement through the train of wheels all the way to the handset on the dial side. Essentially powering the movement backwards to a conventional mainspring movement. Something I find absolutely fascinating. The benefit of this technology is it can be more accurate than a mainspring watch as the power delivery is constant with less deviation. Some of these types of movements from Citizen I believe even reached chronometer standard!
The other beauty of them is that they are always telling time so you can take it off for the weekend and put it back on Monday morning and it be still ticking away and displaying the correct time.
This particular model is a great find as the case and bracelet are pretty much new old stock. This watch has not seen much action and I found out why in the movement. A previous owner had left a battery in it which leaked and stopped the movement. Once I had cleaned it all up and serviced it the watch has sprung back to life.
That dial looks crazy under the crystal and to be honest actually makes it harder to read when on the wrist in bright light but I don’t mind this. For me the 1970s designs are what I collect and just love the bright colours and unusual designs were made in that decade.
Finally, you might have noticed the pusher on the side of the case. Unusual right? This is the watch’s party piece. When depressed the seconds hand flies back to 12. This is for setting the time accurately to the second which is a really useful feature and ensures you can set often and quickly to keep the watch accurate daily. It can also be used as an improvised stop watch. I have not seen this function on any other watch so far and will be looking out for more of these types of Citizen (7801/7802/7803) the most common one I do find is the 7804 which does not have this feature but the movement is still the same platform.
Here is a video on my channel were I show all the insides of this movement while I was servicing it. You can also see it in operation.
I hope you enjoyed this blog and found it useful. Here are my remaining photos of this unusual time piece.
