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Can i trust these readings or is my Timegrapher broken?


AP1875

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Seems it is showing the instant rate every 10 seconds or so under the main display bar. It must average it over some length of time; on a regular Witschi you can set it anywhere from 2-240 seconds (the newer ones will go even longer). I don't know if it's adjustable on that machine.

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The numbers on your screen are the seconds - or + per day, it takes a reading every 10s by default but you can change it to every 20 or whatever suits. The white bar is where you're reading the info that's current.

Firstly you need to find your lift angle for the movement to get the true amplitude, I'm guessing with a watch losing so badly the amplitude isn't really around there.

There are charts to find it but there's a manual way, which is a bit long winded to go into here.

End number which alternates between 28800 and 52 degrees is bph/vph indicating it's a high beat movement and the latter is the list angle which is the default and has to be changed to reflect the movement.

First number is the amount of seconds you're gaining or losing daily and this will fluctuate a little (or a lot depending on movement) 8 different positions.

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If you doubt the accuracy of your time grapher machine, then test it against a known standard.  Use a good quality quartz movement and set the BPS to 1.  Then test the quartz watch on your machine.  It should produce a horizontal line.  If there is any inaccuracy in the internal timebase of the machine, it will show up on the display.

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8 hours ago, robmack said:

If you doubt the accuracy of your time grapher machine, then test it against a known standard.  Use a good quality quartz movement and set the BPS to 1.  Then test the quartz watch on your machine.  It should produce a horizontal line.  If there is any inaccuracy in the internal timebase of the machine, it will show up on the display.

As mentioned above, nothing is wrong withe the machine. Just that the OP couldn't figure out what the numbers displayed every 10 secs and repeated on the top left means.

BTW, quartz watches cannot be used for calibration of a Chinese timegrapher.

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8 hours ago, m1ks said:

End number which alternates between 28800 and 52 degrees is bph/vph indicating it's a high beat movement and the latter is the list angle which is the default and has to be changed to reflect the movement.

Let's also remind here that accurately setting the lift angle only affects the amplitude calculation, and by a small amount of approx 1 to 1 degrees. So it is it not a must or even important thing to do in all cases. 

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Can you post what make and calibre of movement it is, then it’s quite simple to look up the lift angle in a lot of cases. Google for Lepsi Lift Angle and you’ll find lots of info.

 

As for the lines, yep all looks normal (for a poorly running watch). I disagree slightly with some of the above as imho the BE of 1.4 is a bit too high. Sort out that (see if you can get it down to 0.5 or below) and regulate the watch a bit and see what lines you get, I think the amplitude reading is probably miscalculated as the BE and regulation are out. But it’s a good place to start from and I don’t ‘think’ there’s anything wrong with your machine.

 

 

 

Sent from my iPad using Tapatalk

 

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On 7/29/2019 at 11:43 PM, jdm said:

BTW, quartz watches cannot be used for calibration of a Chinese timegrapher.

I'm not clear as to why a quartz movement could not be used as a frequency standard to confirm the accuracy. Can you please help me to understand your reasoning?

The creator of Watch-o-scope recommends using a quartz movement to perform the calibration procedure on that product.  The reason is that the internal oscillator on the sound card of the computer (that forms the frequency standard for the Watch-o-scope) is not operating at precisely the designed frequency and needs compensation.  The quartz movement serves as an accurate input frequency standard.

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36 minutes ago, robmack said:

I'm not clear as to why a quartz movement could not be used as a frequency standard to confirm the accuracy. Can you please help me to understand your reasoning?

I wrote about Chinese timegraphers (the type used by the OP). They only sync to a fixed range of frequency of Swiss escapement,  check  document attached. Calibration is made at the factory with a dedicated input port.

I don't know about instruments or software.

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I checked a movement on my chinese one against a proper professional Witschi (spelling?) one. There was a difference, but it was only a few degrees of amp between the two. I think over the course of several comparisons the biggest difference I had was 4 degrees iirc. I can live with that.  :)

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My 1900 version only goes down to 3600 BPS.  At that setting it will read a Citizen Sky Command at around 0 to +2.   Probably close as it's only claimed to be good to 15 seconds per day without the radio signal and only gets that once a day.

Not good for calibration of anything, but will tell you the machine is functioning.

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On 7/29/2019 at 4:56 AM, AP1875 said:

Can i trust the readings for rate/amp/beat on this timegrapher considering the +/- figures are all over the place? Is there anyway to resolve this?

To resolve the problem with your watch and understand what were seeing we need the background history of the watch the make and model of the watch etc. It's really hard to make diagnostics from just a timing machine display when we don't know the background of the watch what's been done to it etc.

Then if you think you're having a timing machine issue find another watch that you know is working and see what that looks like. But if this is the only watch you have you could purchase the item found at the link below. Designed exactly for this verifying your timing machine is functional. Unfortunately it's probably going to be expensive.

https://www.witschi.com/assets/files/sheets/leaflet_msg.pdf

 

 

 

 

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9 hours ago, JohnR725 said:

To resolve the problem with your watch and understand what were seeing we need the background history of the watch the make and model of the watch etc.

I think it's clear, as mentioned above, that the watch merely needs BE and rate regulation. Don't you agree?

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