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1 hour ago, Hattori said:

I did note their claim on the accuracy of their GPS receiver. I guess they use it to motivate the very high price of their GPS. 

I think similar 😀

Just tested yesterday: a cheap (€ 8.-) neo- 7m receiver showed accuracy of < 0.07 ms per PPS, including all inaccuracy by the displaying software.

The datasheet says, you can switch off some enhancement for positioning, for higher accuracy of the PPS pulse. One simple cfg-switch of the receiver. Maxbe that is what Witschi means. I did not yet switch it off.

Frank

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8 hours ago, Hattori said:

a simple earbud may be even better suited as a transducer thanks to lower impedance that may result in a higher output?

I don't know about an earbud (aren't they crystal, i.e. piezo, elements?) but I tried a small 32 ohm speaker and got no sound. And the LED quit flashing; not a good sign, I thought.

The receiver puts out a 3.3 V signal. Hard to believe we are going to need an amplifier.

And duty factor (or duty cycle) is the duration of the pulse compared to the period.

Edited by wlysenko
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3 minutes ago, wlysenko said:

The receiver puts out a 3.3 V signal. Hard to believe we are going to need an amplifier.

remember the difference between a magnetic speaker is it has a coil. a coil that has resistance 32 ohms versus something made out of piezo that for this discussion is basically infinity. It's not infinity but it basically is. Infinity load on whatever your connected up to will have zero effect 32 ohms might be considered a dead short and drawing too much current. You might need a buffer to drive the speaker.

 

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4 hours ago, Hattori said:

I think Witschi turns on the Snake Oil switch that is hidden inside their GPS box for that kind of money!

I think the reality is that's an old GPS receiver. The old receivers cost more than new receivers. Then a timekeeping GPS costs more than the normal GPS. So witschi just used a really expensive GPS.

Then there is the other problem the problem the Swiss have as far as I'm concerned with all the tools and everything they sell related to watch repair. The problem is every time the cost goes up less people can purchase. Less people purchasing means they have to raise the cost to make up for the items not being purchased at some point in time no one can afford anything from Switzerland and if where lucky the Chinese start cloning things.

But in real life it really doesn't matter. The modern GPS is going to work just fine unless you're really obsessed with absolute perfection then you need to get a timing GPS preferably a modern one.

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51 minutes ago, JohnR725 said:

You might need a buffer to drive the speaker.

 

A buffer in the form of a simple amplifier with one transistor? One like this: 

Simple Single Transistor Audio Amplifier Circuit (theorycircuit.com)

 

simple amplifier.JPG

Edited by Hattori
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On 26/5/2021 at 10:01, Hattori said:

the idea of GPS time based calibration! 

Dear Sirs, I really appreciate all the material you publish, sharing your knowledge and experience with us.
You are the experts, but I can think of something about the WOS calibration process, using a GPS. make a direct cable from the GPS device with 3.5 plug end and connect it to the computer just as we connect the WOS sensor or microphone. As I recall, WOS can be calibrated with any BPH number. It can be 3600BPH, which is the pulsation of a normal quartz watch any known beat number.
Conclusion add a cable with 3.5 plug connector to the GPS device and connect to the computer to calibrate.

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58 minutes ago, wlysenko said:

And the LED quit flashing; not a good sign, I thought.

Thanks for trying! I hope your GPS LED and the PPS output recovered after the test? 

I will try with a simple buffer amp when I receive my GPSes, then.

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43 minutes ago, guidovelasquez said:

Dear Sirs, I really appreciate all the material you publish, sharing your knowledge and experience with us.
You are the experts, but I can think of something about the WOS calibration process, using a GPS. make a direct cable from the GPS device with 3.5 plug end and connect it to the computer just as we connect the WOS sensor or microphone. As I recall, WOS can be calibrated with any BPH number. It can be 3600BPH, which is the pulsation of a normal quartz watch any known beat number.
Conclusion add a cable with 3.5 plug connector to the GPS device and connect to the computer to calibrate.

yes a direct cable from the GPS bypassing basically the timing machine circuitry would be a better way to go.

would probably help to read the spec sheet for the GPS module you using. But I noticed that somebody posted a picture of a nice red colored circuit board using the NEO-6M. I have a link to the tech sheet which is not overly helpful as it doesn't really specify what exactly the output is sort of. This I got link is better it has the schematic which shows it for basically driving and LED.

https://www.u-blox.com/en/product/neo-6-series

http://wiki.sunfounder.cc/index.php?title=Ublox_NEO-6M_GPS_Module

 

 

 

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Hello svorkoetter, any chance there will be a software update that will allow Maximizing the WOS window? Is that a difficult function to accomplish?

Also, any chance there will an update of the positions naming to ISO 3158 standard, i e: CH, CB, 9H, 6H, 3H, 12H?

See examples from Witschi's and ONEOF's manuals:

Witschi programvara1.PNG

ONEOF positions.JPG

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1 hour ago, Hattori said:

CH, CB,

I find it interesting. I have seen different ways of recording the positions and in particular some of them are difficult for me to "visualize". The "icons" mode could even be included. What I don't know what it means is CH CB. I understand that it is dial up or dial down. But I don't understand the meaning of the letters.

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I think the ISO standard is using the French CH, short for Cadran Haut, and CB for Cadran Bas. The other positions are self explanatory. Here is a graphic way of showing the positions, also from Witschi:

 

Witschi NIHS 95-10-ISO 3158 test positions.PNG

Edited by Hattori
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36 minutes ago, Hattori said:

Hello svorkoetter, any chance there will be a software update

I didn't know we can ask for updates? i have three requests two of them are witschi and one of them would be an enhancement to the existing software

I really like how witschi does their time plot feature.

the second witschi feature would be frequency mode. frequency mode tells you the beats per hour of your watch. Handy for watches outside of the normal auto detection range. Once you figure out what you think the ranges supposed to be you can manually set it. Really handy for vintage watches where you end up with all kinds of bizarre timing issues.

Frequency mode has another interesting purpose. When you're in frequency mode the frequency being displayed is used to run the graphical display and unfortunately the numeric display of rate. basically I use this to flatten graphical display if you have a watch running superfast or super slowing and you want to look at the graphical display this makes it flat so you can see that. it unfortunately also displays the rate and if you forget and leave the machine and frequency mode it makes your watch look perfect and the rate looks perfect also. So all you really need is the graphical display to flatten out.

then the last feature is something that witschi does not have but is found in the software. I like to have a second screen for raw mode. Where it does not take into account the rate or the beat. the problem is if you have rate changing the angle it makes it hard to see things. The same for the beat every other tech is out of alignment because as the beat error that would be nice if it would go away. Just make it a lot easier to look at the escapement for analysis purposes.

 

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17 hours ago, Hattori said:

Also, any chance there will an update of the positions naming to ISO 3158 standard, i e: CH, CB, 9H, 6H, 3H, 12H?

This naming may work well for testing complete watches. It does not for the watchmaker on the bench.

When I test a movement in vertical positions, mostly for dyn. poise test/adjustment, I use to look on the mov. side - the side that will be accessed. Usually without its dial. Here the only practical reference is the position of the crown. I don't want to twist my brain, pondering where the "9" may be.

Recently I had to make a french version of my TM software. By the above reasons I did not want to use the ISO names. Unfortunately in French the 1st letters of dial (cadran) and crown (couronne) are the same. So I used H(orizontal) and V(ertical) as 1st letter, H,B,D,G as 2nd (haut, bas, droite,gauche).

Frank

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microphone

2 hours ago, praezis said:

This naming may work well for testing complete watches. It does not for the watchmaker on the bench.

 

20 hours ago, Hattori said:

Also, any chance there will an update of the positions naming to ISO 3158 standard, i e: CH, CB, 9H, 6H, 3H, 12H?

maybe there is a different way to look at the request?

For instance attached is a image from a witschi timing machine notice the cryptic representations that watchmakers don't like? Oh wait they appear to be in English. The witschi machines are programmable for variety of languages or even plain English. So if you have a timing whatever and your making it in more than one language just have the ability to have these other standards. As opposed to it being the only standard and having the watchmaker confused.

 

witschi timing machine designations.JPG

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That is a great piece of software, praezis! I found it some time ago but did not know you are the man behind it. 
I also built your bias powered one transistor amplifier. It is all that is needed, really, I realized after first having built a TO72 based amplifier.

Edited by Hattori
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  • 2 months later...

Hello fellow fans of watchmaking, electronics and DIY.
There has been little activity on this forum but I want to share with you some recent activities where I have used the W-O-S application.
I want to mention that the tool itself is very versatile. And it can help the watchmaker with a lot of his work.
I share here some screenshots and some photographs. They from my recent job.

Pre- Check

Previous analysis.

945159627_RolexOyster1225Full_WindDU2.PNG.cb2078f113ac680b79671ef9ae8fea5d.PNG

Final analysis

 

Analysis in 2 positions.

 

Thanks to the creator of this magnificent tool.

Rolex Oyster 1225 2 Position FW.PNG

 

 

Rolex Oyster 1225 2 Position FW.PNG

 

 

Rolex Oyster 1225 @12H_wind.PNG

Edited by guidovelasquez
Delete duplicate image
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The W.O.S.  software/program is very good and contains most if not all of the features used by most timimg machines.  It takes little effort to build the Amplifier and pickup and you get the satisfaction of you build your own machine, well worth it.      Just to say I have absoloutly NO connection with the people who wrote the programme just think it is a good product.

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My issue with the PC based machine is simply bench space.  That is why I like the Weishi (limited as it is).  It has a small footprint.

When I get a strange reading, I take the watch into my electronic lab and look at it on an oscilloscope (using my custom amp/filter).

Bear in mind...I am an amateur, so my standards may be low...dunno.

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