Citizen Cosmotron 7804A Electronic Watch Complete Maintenance

Рет қаралды 5,095

Күн бұрын

Hi, I'll try to give complete maintenance on a Citizen Cosmotron. Let's disassemble the movement and see what makes it different from other mechanical watches.
I couldn't find any restoration video on this movement - Citizen 7804A. Also, I couldn't find the technical guide on the Internet. I found some pieces of information in Japanese. The normal amplitude range should be 180 - 260 degrees. Since this is not a Swiss lever escapement watch, there should be a beat error. I couldn't find the typical range, though. Other than that, it looks the same as other mechanical watches. Anyway, I might do something wrong in this video. If you have any information about this movement, please let us know.
Thank you for watching. I hope this video helps someone in the future. If you liked this video, please subscribe and leave your like!

Пікірлер: 20

@samnova450 11 күн бұрын

Great job on serving that watch. 2nd Cosmotron that I have seen.

@1rightrev 3 ай бұрын

I just acquired one of these an hour ago. Runs well but date and day setting seem a it wonky. I am a hobbyist watch repair geek and will be using this in the future to service my new vintage find. (surgery on my hand has me out of commission for a while...) I also have an Elnix and a Swissonic. Love these movements! Thanks.

@rossjackson3670 11 ай бұрын

What a brilliant display! Your workmanship and knowledge are phenomenal. A long way to go before I can attempt to work on a watch like this. Thank you for the guidance.

@kewintaylor7056 7 ай бұрын

Very interesting mechanism and maintenance 👍👍👍

@robertp.5410 5 ай бұрын

I have blue bezel Cosmotron, beautiful watch!

@tedblack2415 11 ай бұрын

Such a fascinating movement . nice work as well .

@BlueShotgunShells 9 ай бұрын

Very cool video. Thank you for your work. Will be referring to this video if and when I ever get a citizen model like yours. So Far what i have is the one with the monocoque case with the push lever to reset the seconds hand.

@sde1710 2 ай бұрын

dream!

@enricosperoni720 5 ай бұрын

Many thanks for sharing your knowledge and work. The footage is also of excellent quality. What can you say about the precision of these mechanisms?

@vintagewatchtinkerer 5 ай бұрын

Actually, not so good. The precision will be the same as other standard mechanical movements because the basic mechanism is the same. We can adjust the beat rate by tuning the regulator.

@gabrielmamasig8694 4 ай бұрын

I have a similar watch 7803A and got my watchmaker to “service it” however it always loses time (usually a couple of minutes per day or even hours) which made the watch unwearable. I was wondering if you knew what would the problem be? I noticed that it does not gain or lose time when it is on a crown down position (my watchmaker cannot also infer what the problem is). Would appreciate any insight. Thanks and great video :>

@gabrielmamasig8694 4 ай бұрын

The watch runs at +/- 1 sec per day according to a timegrapher but still the problem persists

@vintagewatchtinkerer 4 ай бұрын

I'm sorry for late reply. The balance assembly may have an issue. The balance wheel has a magnet so it might have metal dust. In that case, you may hear a scratching noise when you tilt the watch. It will be worth checking.

@dominikmlinaric7922 4 ай бұрын

Hi, can you please write which battery did you use? I have the same watch but I have problem with finding battery. The problem is that the watch was running normaly but after I replace the battery it just stoped working after 6 days..do you think that wrong battery on this watch can ruin mechanisam or something? Thanks!

@vintagewatchtinkerer 4 ай бұрын

I used an SR44/313 battery. I don't think the movement is picky about the battery. Did you check the battery voltage after stopping? If there is still about 1.5V left in the battery, the battery is good. The movement may have a mechanical or electrical problem.

@eloygagogonzalez7330 10 ай бұрын

😍😍😍😍

@vintagewatchtinkerer 10 ай бұрын

😉

@user-kb7wp1nr8z 7 ай бұрын

What size screwdriver did you use?

@vintagewatchtinkerer 7 ай бұрын

I mainly uses 1.2 mm and 1.0 mm. Sometimes I use 0.9 mm or 0.8 mm but it's rare. In my experience, the shape of the tip is more important than the width. I use a sharpening stone before using it. But I need more practice.

@user-kb7wp1nr8z 7 ай бұрын

@vintagewatchtinkerer Thank you very much. I appreciate the advice.