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As Guido said, the culprit is probably the shielding of the cable from the piezo. Make sure that (a) you are using an actual shielded cable (not just two wires in a plastic sleeve), and (b) the shield is connected to the outer brass disk of the piezo (not to the smaller inner circle).

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20 minutes ago, svorkoetter said:

As Guido said, the culprit is probably the shielding of the cable from the piezo. Make sure that (a) you are using an actual shielded cable (not just two wires in a plastic sleeve), and (b) the shield is connected to the outer brass disk of the piezo (not to the smaller inner circle).

 

Right now I am using the MicroSet Watch Timer clamping watch sensor (attached image of sensor). The plug on the unit is a 3.5mm stereo connector. As the unit is a mono pre-amplifier, the clamping watch sensor pin out for the piezo microphone is on the ring connection and not the tip. So I had to use some alligator clips to see if it would even work. The alligator clips are probably the culprit as there is no shielding on the wire and just the plastic sleeving. I may pick up the Timetrax sensor from Adams Brown Co.

- Garrett

clamping4.jpg

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6 minutes ago, svorkoetter said:

Does the MicroSet unit use the tip for anything? If not, you could just open up the plug (assuming it's openable), and wire the tip and ring together (so both stereo channels receive the signal).

I opened up the unit and the piezo has the red wire connected to the small side and to the ring of the stereo connector. The shield is connected to the large side of the piezo and to the sleeve of the stereo connector. The white wire is unused and not attached to anything. I could cut the wires and resolder the red and white to the small size of the piezo and resolder the shield. I just have to remove the hot glue that is inside of the unit to keep the cable from moving. I will post a picture of inside of the unit soon.

 

- Garrett

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I'd make changes at the plug end by snipping off the original 3.5mm stereo plug and replacing it with a 3.5mm mono plug (assuming the Microset unit is only going to be used for connecting to a PC line input).  It looks like the original plug is sealed and not able to be opened.

Check for ground loops as well - places where cables that join different equipment together may be grounded at both ends.  This could be present in interconnect cabling or in power cabling.  If found, disconnect one end of an offending ground to break the loop.

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What Rob suggests is probably best, but if you are going to do it at the piezo end, I'd suggest carefully removing the insulation from a short section of the red wire, about half way between the piezo and where it enters the cable, and then soldering the end of the white wire to it. The shield is fine as-is, and I would not recommend unsoldering and resoldering the piezo, as it is easily damaged.

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So I rewired the clamping sensor and attached both the red and white wires to the piezo. The buzzing has gone down considerably, but there is still some hum which is most likely related to the AC power. If I unplug the unit there is still some power to the preamp in which the humming goes away. I will have to look into making a battery pack for the unit. I installed the equalizer apo software and peace. I modified the eq to limit the humming from what was on these threads. The issue I am running into now is that Watch-O-Scope will not open up the line-in device saying that the format is not compatible. I have no issues with using the open source timegrapher software "tg" and it is pretty much on par with my MTG-1900 timing machine.

- Garrett

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7 hours ago, garrettwp said:

 

Right now I am using the MicroSet Watch Timer clamping watch sensor (attached image of sensor). The plug on the unit is a 3.5mm stereo connector. As the unit is a mono pre-amplifier, the clamping watch sensor pin out for the piezo microphone is on the ring connection and not the tip. So I had to use some alligator clips to see if it would even work. The alligator clips are probably the culprit as there is no shielding on the wire and just the plastic sleeving. I may pick up the Timetrax sensor from Adams Brown Co.

- Garrett

clamping4.jpg

Hi friend, you are doing a great job for the community of watchmakers and watchmakers. Thanks for the photos showing the inside of the Micro Set unit. On using Peace, it works fine on window 7 but not on windows 10. I have a suggestion on how to reduce noise with the help of Peace. Http://reparacionderelojes.weebly.com/watch-o-scope-mic.html
It is very efficient. I want to ask you if you are going to get the TimeTrax microphone to show us the results. And I have great interest in seeing what is inside TimeTrax.

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Hi. On the Micro Set Microphone, I can think of an idea. I've done it before with a DIY microphone. You can cut pieces of thin aluminum foil. I keep it from the seals on the milk cans.

590cf3bbe0275_Sellodeleche.thumb.JPG.613fa6a59fedd1a100a80e53bf6c74a9.JPG

Cut pieces with scissors to fit inside the Micro Set sensor. That considerably reduces the AC buzz of the network.

Here I leave a link that can be useful to modify a preamplifier that I use the cost is very reasonable and the results excellent.

http://reparacionderelojes.weebly.com/modifying-pyle-pp444.html

See the settings I use. And the results.

590cf4d073ee9_SetUpMicEng.thumb.JPG.33d71b775853a2d349a2513cb9947afa.JPG

Here with Elma Microphone Mini tests 70s.

With Microphone DIY. Constructed from pickups for guitar.

590cf60682de1_WhatsAppImage2017-05-05at15_47_03.thumb.jpeg.cc630e5843d8b372c19eadec70dcd601.jpeg

And the results:

590cf711c9516_ConmicDIY.PNG.ef2cfe0e36f1aeab6e4f5695976c8fc4.PNG

Guido

Edited by guidovelasquez
No name end.

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I ordered the TimeTrax sensor as the modification to the Microset clamp sensor caused it to be unusable with the Microset timer. So I removed the modification that I made to the Microset clamp sensor. I believe as a non destructive mod for the Microset senor is to pick up a stereo to mono adapter. I also have a few 12V DC battery packs that were shipped with some equipment I have installed in the house. I forgot I even had them and pulled them out of the box. I have them charging now and will be using them with the Rolls microphone preamp to eliminate the ac hum. I have to modify the barrel connector as the polarity is different between the battery packs and the preamp. 

- Garrett

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So I received the TimeTrax sensor and hooked it up real quick. It still requires a microphone preamp. I rewired a cable so that I can use the 12V lithium ion battery packs I had around for the Rolls mp13 preeamp and the output is mostly dead silent. I was getting very good results with the open source tg software compared to my MTG1900 time grapher. Watch-o-scope was having some little issues and the readings were a little off. I may have to tweak the settings a bit.

If you are okay with shelling out $95 for a sensor, the TimeTrax is a really nice kit. It is heavy and solid. My only issue is that testing in some of the different positions will be an issue due to the design of the holder. When placing the crown of the watch on the sensor, to position the sensor so the watch is crown up or crown down will pose an issue due to the placement on the holder and the adjustment screw to tighten the clamp. I will try and get pictures to explain better. 

I will be doing more tests and hopefully come up with a list of parts that others may use if they do not want to build their own from parts.

- Garrett

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So for those that want to see what's inside the TimeTrax  Watch pickup images attached. The sensor itself the disc is 15 mm in diameter the piezo is 10 mm. You'll notice it's covered with hot glue I suspect that's to minimize picking up audio it would have a dampening effect. It's mounted to a spring-loaded pin and I have images of it in and out so it doesn't have to go in very far it just has to pick up the vibrations. Then the one I have is considerably older which is why it has a metal movement holder versus the newer out of plastic.

I was thinking now that we have 3-D printers readily available we could probably design something ourselves. I imagine a lot of the cost was having the original plastic injection molded.

tt6.JPG

tt5.JPG

tt4 out.JPG

tt3 in.JPG

tt2.JPG

tt1.JPG

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Thank you for sharing the information on the construction of commercial microphones. With that information maybe we can make our own microphones.:Bravo:

We would also like to see a picture of the waveform to see the signal level noise.

Thank you

Guido

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From my tinkerer point of view, I think that microphone is a bad design! You have that "pin" and that glue that I think is 10 times heavier than the pieso sensor. It is dead weight!

IMHO the sensor should have the lowest mass possible (be light as posible) to pick up the watches vibrations with the highest efficiency. It should be in direct contact with the watch crown.

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I'm getting a clean, stable and reproducible signal with timetrax plugged into linep (amp) plugged into sound card.

Software wise PEACE and WOS is all I have.

7ac71237921165c47be34f162fc4ea6f.jpg

db000c35cb161bf683b27876a2d1e8a0.jpg

5a23a90fe82f1054ca9be95e807a4455.jpg

ec9602d4b7ad7a9e681cd88ced4a9d9e.jpg


This is on a standard Lenovo desktop with cables everywhere of normal shielding.

Cheers!


Sent from my iPhone using Tapatalk

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Hello

I make amplifier my self follow this site http://www.watchoscope.com/amplifier.html

I can hear sound from piezo disk when I tap a disk. But I cannot hear tick-tock sound when I put a watch at piezo disk.

What wrong , How do I check

Did You try multiple watches? Place the crown to the piezo! Does it have a screw down crown? Then screw it out and then place it to the piezo! 

To see tapping gives a signal shows that the connections are ok, but the ticking of a watch is way way smaller mechanical impact. 

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Did You try multiple watches? Place the crown to the piezo! Does it have a screw down crown? Then screw it out and then place it to the piezo! 

To see tapping gives a signal shows that the connections are ok, but the ticking of a watch is way way smaller mechanical impact. 

I try with many watch I have . The result is same I cannot hear watch sound

I place a crown to piezo disk I cannot hear any thing but noise is very loud when I adjust volume R7

 

wos.png

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I try with many watch I have . The result is same I cannot hear watch sound

I place a crown to piezo disk I cannot hear any thing but noise is very loud when I adjust volume R7

 

wos.png

Seems like a 50Hz main current noise to me. use PEACE to filter the frequencies not needed!

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Seems like a 50Hz main current noise to me. use PEACE to filter the frequencies not needed!

Thank you very much szbalogh

So it is impossible to use amplifier only right?

I will have to use PEACE or other equalizer software to filter the frequencies not needed

Are there other preamps circuit ? That sounds is clean without using eq software.

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I suspect that what you are seeing is not 50Hz mains noise. I use the same amplifier without any EQ software with no issues. I would suggest first double-checking that you didn't make any mistakes building the amplifier or connecting it to the microphone.

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