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It Is Ok Or Not ?

RicardoG
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RicardoG Watch Enthusiast

RicardoG

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In a very know site of trades, I found for sale a 7750 Valjoux movement. The photos show the movement and this one:

 

$_57.JPG

 

The seller in the description say: The movement is in excellent condition and works perfectly !!!

 

In my opinion (if I can read correctly the timer graphic), it have some problem at the escapement weel or in the followed weel.

 

Am I correct or not? Some other opinion?

 

 

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RicardoG Watch Enthusiast

RicardoG

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Well, in my opinion (I can be wrong, that's why my question) the periodically split of both lines show some problem in some tooth of scapment weel or in the followed weel (may be a bent weel). Anyway, if it is OK, why this periodic split? Why not a continuous line?

As I said, I can be wrong, but if I service one movement and it shows that graphic, I will search a little more for what is causing this kind of hiccup.

 

Ricardo

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Mark Distinguished Member

Mark

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The timing machine is showing two lines. When the watch is perfectly in beat they overlap and appear to be one line. What you are seeing is slight fluctuations in the beat which is very very minimal and not something to be concerned about.

Sent from my iPhone using Tapatalk

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JohnR725 Distinguished Member

JohnR725

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The problem you're seeing is a problem with digital displays for timing machines. So a confusing description you see one line because it's in beat. The digital numeric display indicates that your watche is running one second fast that means the line is going to have to slope upward by a very tiny amount. So the degree of the angle is so tiny the graphical display can't show it so instead it shows it being absolutely flat then a transition where you see the one in zero pixels weird staircase effect sometimes that it shifts up by one pixel to tell you it's going fast.

 

This is one of the irritating characteristics of a digital machine versus the paper tape machine is the difference between one and zero always give that weird pattern of some fashion. The solution for a watch like this is to switch to a timing machine that has a resolution of +-99 Versus your current machine which has a resolution of +-999 seconds. Then much more expensive timing machine such as witschi you can change the magnification on the screen and expand the lines but you still stuck with the pixels you'll never get it absolutely perfect linear display unless you have super tiny pixels.

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RicardoG Watch Enthusiast

RicardoG

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The problem you're seeing is a problem with digital displays for timing machines. So a confusing description you see one line because it's in beat. The digital numeric display indicates that your watche is running one second fast that means the line is going to have to slope upward by a very tiny amount. So the degree of the angle is so tiny the graphical display can't show it so instead it shows it being absolutely flat then a transition where you see the one in zero pixels weird staircase effect sometimes that it shifts up by one pixel to tell you it's going fast.

 

This is one of the irritating characteristics of a digital machine versus the paper tape machine is the difference between one and zero always give that weird pattern of some fashion. The solution for a watch like this is to switch to a timing machine that has a resolution of +-99 Versus your current machine which has a resolution of +-999 seconds. Then much more expensive timing machine such as witschi you can change the magnification on the screen and expand the lines but you still stuck with the pixels you'll never get it absolutely perfect linear display unless you have super tiny pixels.

 

Nice John, and good explanation. I have a B200 and the lines as you said, are continuos. As I don't have (yet) a digital timer, didn't cross my mind that is a problem of resolution of display. As Morten, I try to analyze the graphics. It can show more than we believe.

Thanks for all.

Edited by RicardoG
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canthus Super WRT Addict

canthus

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Could it also be feature of the sampling period set for the timer and the accuracy of a budget timergraph.  Maybe short period is set.  Would setting to longer period give a longer steady line?

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MortenS Watch Enthusiast

MortenS

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Interesting read , I have a cheapo time grapher and have tried to find info on how to interprete the results. Do you have any more info like that morten?

 

Mark beat me to post it. :)  The rest of the picture I posted you can find here.

 

http://www.witschi.com/assets/files/sheets/Witschi%20Training%20Course.pdf

 

Morten

Edited by MortenS
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