Jump to content

Recommended Posts

1 hour ago, guidovelasquez said:

I have an opinion. The low-beat watches are very quiet. (18800 bph), the high beat and inside the case, are very quiet and you need to increase the gain. As the gain increases, it is more likely to have a retro feed. But I agree with szbalogh , which says: "Check if" listening to this device "is not marked on the microphone properties.". That would be the first point to correct. I have the idea that if you check the watch out of the case, the problem will not occur.

Hi Guido, you're right, it only happen with hi beat watches, it come and go in constant interval, it's more like resonance inside the watch case. i haven't try the movt out of the case, but if that is the solution it will bother because if u want to check many watch you must pull it out of the case..

Share this post


Link to post
Share on other sites

This resonance in case is strange becouse i can hear that in my HMT-s (18000bph) and chinese gmt (dg2813, 21600bph) as well but non of them making noise in the tiemgrapher. As You said, the jingling come and go in regular intervals. I like to listen to it while going to sleep :) 

Share this post


Link to post
Share on other sites
1 hour ago, szbalogh said:

This resonance in case is strange becouse i can hear that in my HMT-s (18000bph) and chinese gmt (dg2813, 21600bph) as well but non of them making noise in the tiemgrapher. As You said, the jingling come and go in regular intervals. I like to listen to it while going to sleep :) 

18000 and 21600 bph also make case resonance when you put the watch on ear, but true, none of them mess the timegrapher reading, only the 28800 bph watch. i wonder are the 28800 resonance problem mess the reading when measure in regular timegrapher (ie No.1000 and No.1900 timegrapher)?

Edited by FHP

Share this post


Link to post
Share on other sites

I just ran your echo recording through a spectrum analyzer, and the buzzing echo sound is at 581Hz and multiples thereof. The peak is at the seventh harmonic and it goes down from there in both directions. That's the same sort of spectrum a bowed string instrument has, so there's probably something thin resonating in your watch microphone or stand.

 

resonance.png

Share this post


Link to post
Share on other sites
On 29/7/2017 at 11:36 AM, FHP said:

answering your first question, there is only one recording device on my laptop, external mic, and i have turn off the speaker, but the problem persist.

I will try with the movt out of the case. i'm also use equalizer APO to filtering unwanted noise.

Hello, now I just examined the waveform that we have shared. It looks like a resonance effect. I know very little of electronics but I can think that the effect is due to a capacitor maybe an electrolytic capacitor that is charged and discharged generating that effect. If you have a photo of your preamplifier circuit I would like to see it.

I also believe that it can improve the signal with the APO EQ.

Guido

Share this post


Link to post
Share on other sites
On 7/30/2017 at 6:37 PM, svorkoetter said:

I just ran your echo recording through a spectrum analyzer, and the buzzing echo sound is at 581Hz and multiples thereof. The peak is at the seventh harmonic and it goes down from there in both directions. That's the same sort of spectrum a bowed string instrument has, so there's probably something thin resonating in your watch microphone or stand.

 

resonance.png

Dear Stefan, attached is my mic stand, i use felt as cushion, is there anything than can cause resonating?

Mic.jpg

Mic2.jpg

Share this post


Link to post
Share on other sites
13 hours ago, guidovelasquez said:

Hello, now I just examined the waveform that we have shared. It looks like a resonance effect. I know very little of electronics but I can think that the effect is due to a capacitor maybe an electrolytic capacitor that is charged and discharged generating that effect. If you have a photo of your preamplifier circuit I would like to see it.

I also believe that it can improve the signal with the APO EQ.

Guido

Dear Guido, attached is my preamp pics and circuit diagram (i use diagram from watchoscope.com), i use MKM capacitor because miller and ceramic capacitor is unavailable, can this cause the problem?. BTW i already use equalizer APO to filter unwanted freq.

Preamp.jpg

circuit.jpg

Share this post


Link to post
Share on other sites

From the pictures, I suspect that the resonance you are getting is physical, not electronic. That yellow plastic around the microphone might be resonating, or whatever is behind it might be. Did you use a bare piezo element, or is it enclosed in some sort of plastic housing. If it is enclosed, _that_ might be resonating.

Share this post


Link to post
Share on other sites
5 minutes ago, svorkoetter said:

From the pictures, I suspect that the resonance you are getting is physical, not electronic. That yellow plastic around the microphone might be resonating, or whatever is behind it might be. Did you use a bare piezo element, or is it enclosed in some sort of plastic housing. If it is enclosed, _that_ might be resonating.

I use bare piezo element and i use foam double tape behind it. update : i just try my tissot 2836-2 with 28800 bph and it measure perfectly (pics attached), no resonance. it seems only my rolex sub that cause the resonance.

20170731_215358.jpg

tissot 2836-2 28800.jpg

Share this post


Link to post
Share on other sites

The resonance is probably caused by a combination of factors. Perhaps with some watches, the yellow plastic dish vibrates against the plastic of the watch holder? I would suggest removing that dish entirely, since its shape will cause echoes, and the edges can easily vibrate.

Share this post


Link to post
Share on other sites
8 hours ago, FHP said:

I use bare piezo element and i use foam double tape behind it. update : i just try my tissot 2836-2 with 28800 bph and it measure perfectly (pics attached), no resonance. it seems only my rolex sub that cause the resonance.

20170731_215358.jpg

tissot 2836-2 28800.jpg

Dear FHP, Thanks for the pics. They are teaching me many things. Congratulations on the work of the preamplifier.

  I can make a suggestion. The foam disc adhered to the electric piezo disc attenuates the most important frequencies of the clock sound. If you leave the metal disk uncovered as seen in the photograph, I'm sure it will have a better sound.

 

Guido

Share this post


Link to post
Share on other sites
20 hours ago, svorkoetter said:

The resonance is probably caused by a combination of factors. Perhaps with some watches, the yellow plastic dish vibrates against the plastic of the watch holder? I would suggest removing that dish entirely, since its shape will cause echoes, and the edges can easily vibrate.

already removes the yellow plastic, resonance problem still exist..

Share this post


Link to post
Share on other sites
12 hours ago, guidovelasquez said:

Dear FHP, Thanks for the pics. They are teaching me many things. Congratulations on the work of the preamplifier.

  I can make a suggestion. The foam disc adhered to the electric piezo disc attenuates the most important frequencies of the clock sound. If you leave the metal disk uncovered as seen in the photograph, I'm sure it will have a better sound.

 

Guido

Dear Guido, the purpose of white plastic in front of the piezo disc is to prevent dent on the piezo disc surface when fastening the watch crown toward the mic, but indeed it may reduce the sensitivity of the mic, i will find another way to prevent the dent.

Do you have experience when measure a rolex sub with watch o scope?, why is it so hard to measure that watch?

Share this post


Link to post
Share on other sites

Dear FHP, I do not have a Rolex Submariner in my hands. But I have some that resemble him.

 

Regarding the plastic piece that covers the piezo, it definitely alters the sound of the watch. The Piezo is actually a "vibration sensor". And plastic is a bad driver of vibration. I have an original microphone from a time control machine. (Timing machine). Brand Elma. And the sensitive parts are metallic. And curiously they do not pretend to "touch" the crown, but rather the "case" of the wristwatch.

5981511fd9780_WhatsAppImage2017-08-01at10_08_34PM.thumb.jpeg.8accca3420ec5641375ae2a7bbbb258a.jpeg

 

My experience on these watches, is that the steel case very robust, attenuates the sound considerably.

 

On the other hand, I can make a suggestion from the information you share. You say: 'I use the plastic on the piezo in order to avoid denting.'

I think you're squeezing the microphone stand too tight. In doing so, some things happen: it flexes the piezo and deforms it with what changes its acoustic response.

 

Guido.

Share this post


Link to post
Share on other sites

I' m pretty sure the resonating noise is come from the movement inside watch case. I stick my ear in the the watch, when the resonating noise come, the scope mode in WOS i going crazy, like wave that come and go (video attached). BTW  i already replace the piezo disc with the new one, install it without yellow and white plastic guard. I've also tried clamp the watch into piezo disc without watch holder, the problem still occur..

Resonating Vid.mp4

Share this post


Link to post
Share on other sites

I'm okay with Franck. Although I could influence several factors, I still suspect that something in the construction of the DIY Pre amp is affecting the resonance. Clocks tend to have periodic resonance moments. And if the design in the pre-amp DIY accentuates that resonance that can affect.

About EQ The only observation I can make is that at 16kHz there seems to be little useful information about the watch sound. It is just my opinion.

 

Guido

Share this post


Link to post
Share on other sites

Hello everyone here.

I was searching web to find solution for mechanical and tuning fork watch timing and ended up here. My old B-200 starts to be old and tired, so I am looking for something to replace it. And I do not have tuning fork card to it

I see that here have been made extraordinary work. I raise my hat by both hands to people prototyping this project in electronics, software and mechanics aspects. I understand electronics and softwares only so much, that I know not to start my own design.

I have a maybe stupid question (sometimes answer might be as stupid as the asker seems to be...) because my knowledge about computers is limited to "when it does not work, carry it to the recycling area and do it in a good old way without".

Is there any not normal or laptop type device in market which can be used for this project? My workshop does not have table top room for computers and something smaller may be hided inside some old style case to give illusion not to be so modern. Yes, I may be old style jerk but pretty proud of not having a smartphone.

-ep-

 

Share this post


Link to post
Share on other sites

What an entertaining dissertation and at the same time amusing! I like a statement that is engraved on my Nort Face sweatshirt. It says "Never Stop Exploring." So you came here, and welcome.

Let's see if I understood your question. (English is not my native language, Not even my second language is only Spanish and with technology helped me translate).

You ask if there is a more discreet device than a laptop or PC to put on your workbench?

Maybe this is: https://www.ebay.com/itm/Mechanical-Watch-MTG-Coaxial-LCD-Tester-Timing-Multifunction-Timegrapher-NO-1000-/142498664283?hash=item212d950f5b:g:vJEAAOSwo-NZr0zl

59ed6c1d5014e_TimeGraph.jpg.a17c938e266f5d1cb39b7e87ef6c81fe.jpg

And do not worry about being at odds with technology. I also often wish I was born about 25 years later .... But then I would not have missed some valuable events and experiences.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...