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Citizen 7803A Cosmotron Beat Error?

dstella

By dstella
in Watch Repairs Help & Advice

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dstella New Member

dstella

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Hi all - I have a new (to me) Cosmotron that is running fine at +15 seconds a day (actually great, since it does that in all positions!) but I am curious about the apparent massive beat error: 7.6ms. Adjusting the hairspring stud (which on a mechanical watch would change this) does not affect this at all (maybe by 0.3 at most). I am content to leave well enough alone, but is this type of error normal on Cosmotrons? Or is the timer having difficulty listening to it? I have had issues with plastic watches (Siderals, Swatches, etc.) that have to be oriented differently due to plastic cases, so it would not be surprising if it's a timer issue.

Thanks!

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rogart63 Distinguished Member

rogart63

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I usually put the crown to the metal part on the Timegrapher. i don't know what kind of TG you have. So can't say how to put the watch. But even if it's a plastic case or a well enclosed case it works fine to put the crown to the metal which holds the case. 7,6 beat error sounds a lot. 7803A isn't that a electronic movement with balance? 

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