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3 hours ago, Jdg123 said:

How do I reduce the noise so I can uncheck the button again and get good readings? 

It seems you have solved your problem but if you still have a noise problem I wonder if some of it is line-frequency noise. You are using an amp that plugs into wall power. Whenever I add something to my setup that plugs into wall power, like a signal generator or scope, I get 60 Hz noise. I cured this by using a ground loop noise isolator. My unit is this: https://www.amazon.com/gp/product/B019393MV2/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&th=1

I put this between the preamp and the computer and it solves the problem. The isolator takes 3.5 mm stereo cables but mono plugs work.

Edited by wlysenko
spelling error
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6 hours ago, Jdg123 said:

pickup going through this guitar

I can additionally suggest that it removes the rubber insulation on the pickup, that works as a low pass filter and leaves out the most important frequencies for analysis in the WOS. The final captures are very clear that facilitates the work of WOS. Also I see on your Marshall amp, the tone control turned clockwise, if that raises the low frequencies, it should be on the other end. Good job.

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2 hours ago, wlysenko said:

It seems you have solved your problem but if you still have a noise problem I wonder if some of it is line-frequency noise. You are using an amp that plugs into wall power. Whenever I add something to my setup that plugs into wall power, like a signal generator or scope, I get 60 Hz noise. I cured this by using a ground loop noise isolator. My unit is this: https://www.amazon.com/gp/product/B019393MV2/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&th=1

I put this between the preamp and the computer and it solves the problem. The isolator takes 3.5 mm stereo cables but mono plugs work.

I might look into that, thanks

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Hi Jdg123,

I sent your soundsample through my timing machine.
Unfiltered, it is very low and shows huge noise, exactly hum:

PCTM2.jpg.8c42e7ee0ac1ea9c5c177a8cb3bc360b.jpg

With filter on, evaluation is sufficient:

PCTM1.thumb.jpg.8dbf1adfe22c62032f6fda8c22300b27.jpg

Frank

Edited by praezis
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11 hours ago, praezis said:

Hi Jdg123,

I sent your soundsample through my timing machine.
Unfiltered, it is very low and shows huge noise, exactly hum:

PCTM2.jpg.8c42e7ee0ac1ea9c5c177a8cb3bc360b.jpg

With filter on, evaluation is sufficient:

PCTM1.thumb.jpg.8dbf1adfe22c62032f6fda8c22300b27.jpg

Frank

Hmm, not what Im seeing That recording looks like the one from the transistor mic or the regular piezo disc mic, and from a 2892 movement maybe.   They were noisy, the WOS I made was a bit worse, but seems to have a little higher gain.  Im curious to see a trace from a WOS that others have built.  I did notice that when I record on my laptop I get a weird hum when turned way up, but it doesn't do it on my other pc that I use in the shop.  Also until recently I did't have decent shielded cable, whenever you even pass your hand by the cable it would start to hum.   I bought some really nice cable but have been too lazy to put plugs on them yet, going to use xlr.  I will use it when I get the updated version done.

The 4th pic is without anything on the mic. 

The 5th pic is with a watch on the mic,

the 6th pic is with the amp turned off. 

The last pic is from the PC microphone (everything unplugged.)

Seems pretty decent.  This is in a noisy room with Florescent lights, 6 inches from my PC, connected with a very crappy, shielded cable. 

I am not sure how to get a decent reliable audio recording, perhaps I am doing something wrong.  It seems My amp is actually quieter than anything else I have plugged into this PC....  Maybe it is my sampling settings or something?  But all that being said I can not reproduce the hmm that you have in your screenshot.  What version of the software do you have, where did you get it?  My copy is different than yours.  Thanks so much!  I have tried a few different preamps so far, nothing has worked as well as this one, the WOS was very close and may have been better, I didn't have this new mic I made when I tested the WOS.  When I am not under all these lights things seem to quite down a little but not much.

My expeirance has been that regular disc piezos are sensitive but very noisy, the transistor amp is far worse, the vibrograf mic works great, and the last mic I made based on the vibrograf works better but has slightly lower signal strength, it picks up almost no background noise.

I see that others have got the transister ones to work but I have not been able to get decent results

I did notice something strange lately...  Im getting an odd "rubbing" "clicking" sound randomly, and even when there is nothing in the mic there sometimes will be a random increase overall in gain, then it levels back off.  Just started the other day.  I have been handling this board pretty roughly and trying different components so I figured I damaged something.  I also have been attaching and removing various sensors to it.  Strange

Thank you very much for your help and insight.

Screenshot 2021-04-06 19.58.28.png

Screenshot 2021-04-06 19.59.19.png

Screenshot 2021-04-06 19.59.42.png

Screenshot 2021-04-06 20.08.47.png

Screenshot 2021-04-06 20.15.17.png

Screenshot 2021-04-06 20.16.37.png

Screenshot 2021-04-06 20.25.35.png

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On 4/5/2021 at 2:32 AM, Jdg123 said:

Tg seems to be able to handle your sample just fine.  There is a lot of low frequency noise, but the 3kHz high-pass filter takes care of it well.  There is a big glitch on the paperstrip about every 22 seconds, because that is when the audio sample loops.  The smaller glich about 17 seconds sounds like muffled thumping, as one gets when the microphone or watch is being moved.

image.thumb.png.38015fab0fbe0cbe01f10c4603a20340.png

Here is a spectrogram.  We can see the ticks, as well as lots of noise in the < 2kHz range, as well as something at about 16 kHz.

image.png.866e4af48ab8cc1eb94fda5ff83f1be1.png

Here's a closeup of the < 3kHz noise.  Definitely something very large at about 710 Hz.  I'm not sure what is going on at 1.9k and 1.1k.  Maybe the microphone holder is vibrating on the watch?  It seems like the movement is causing something to resonate one of two frequencies for an entire beat or more.

image.png.2066516f362926af5f354af5c3821dad.png

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7 hours ago, CWRNH said:

What version of the software do you have, where did you get it?  My copy is different than yours.  Thanks so much! 

I use PCTM (PC Timing Machine).

1 hour ago, xyzzy said:

Definitely something very large at about 710 Hz. 

That´s what I called hum on my scope, actually a bit higher than hum (I calculated 725 Hz from the scope picture).

Frank

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14 hours ago, xyzzy said:

Tg seems to be able to handle your sample just fine.  There is a lot of low frequency noise, but the 3kHz high-pass filter takes care of it well.  There is a big glitch on the paperstrip about every 22 seconds, because that is when the audio sample loops.  The smaller glich about 17 seconds sounds like muffled thumping, as one gets when the microphone or watch is being moved.

image.thumb.png.38015fab0fbe0cbe01f10c4603a20340.png

Here is a spectrogram.  We can see the ticks, as well as lots of noise in the < 2kHz range, as well as something at about 16 kHz.

image.png.866e4af48ab8cc1eb94fda5ff83f1be1.png

Here's a closeup of the < 3kHz noise.  Definitely something very large at about 710 Hz.  I'm not sure what is going on at 1.9k and 1.1k.  Maybe the microphone holder is vibrating on the watch?  It seems like the movement is causing something to resonate one of two frequencies for an entire beat or more.

That’s interesting, I did feel like TG did handle my signal better, but the functions on the watch o scope are cooler. + I think I got it working pretty well now.  
 

the watch sounds a bit weird and echo-y even when you hold it up to your ears. 
the watch Is held on the pick up with the pressure of the padding in the watchbox, I don’t think it would move or vibrate. 
 

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On 4/2/2018 at 5:08 PM, guidovelasquez said:

Thanks for the very informative images.
I use a microphone from an old time machine. here goes the image and I can show you images of its interior.

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

IMG_9387.JPG

H Guido, I have a microphone from vibrograf, could you share how did you change the original jack? Thank you

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On 4/2/2018 at 5:08 PM, guidovelasquez said:

Thanks for the very informative images.
I use a microphone from an old time machine. here goes the image and I can show you images of its interior.

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

IMG_9387.JPG

Hi Guido, I have a microphone from vibrograf, could you share how did you change the original jack? Thank you

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On 4/2/2018 at 5:08 PM, guidovelasquez said:

Thanks for the very informative images.
I use a microphone from an old time machine. here goes the image and I can show you images of its interior.

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

IMG_9387.JPG

Hi Guido, I have a microphone from vibrograf, could you share how did you change the original jack? Thank you

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47 minutes ago, Fred said:

how did you change the original jack?

Hi Fred,
about changing the Jack or connector. below I show photographs. It is actually very simple, the cable has a central wire that is the one that carries the signal and a shield that is the ground line.
I replaced the entire cable. At one end it has an RCA connector, from the original cable that I bought of good quality. in the other I placed the original connector of the Timing Machine, Elma, Made In Germany. The photographs go.

IMG_7222.thumb.JPG.9927283440720888923c27e81b370742.JPGIMG_7224.thumb.JPG.879ba199d3a173c73387bbf04fbdfea1.JPGIMG_7229.thumb.JPG.269491d514ba1fb86a6a65bcb52b5ec1.JPG

IMG_7235.thumb.JPG.0ba29ff22a559eaba3c889630a202ba9.JPG

IMG_7230.JPG

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On 4/8/2021 at 10:21 PM, guidovelasquez said:

Hi Fred,
about changing the Jack or connector. below I show photographs. It is actually very simple, the cable has a central wire that is the one that carries the signal and a shield that is the ground line.
I replaced the entire cable. At one end it has an RCA connector, from the original cable that I bought of good quality. in the other I placed the original connector of the Timing Machine, Elma, Made In Germany. The photographs go.

IMG_7222.thumb.JPG.9927283440720888923c27e81b370742.JPGIMG_7224.thumb.JPG.879ba199d3a173c73387bbf04fbdfea1.JPGIMG_7229.thumb.JPG.269491d514ba1fb86a6a65bcb52b5ec1.JPG

IMG_7235.thumb.JPG.0ba29ff22a559eaba3c889630a202ba9.JPG

IMG_7230.JPG

Hi Guido, thanks a lot for the tips and pics, thats really what i needed. great pics

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  • 2 weeks later...

I am wondering if someone can help me find the data sheets for this. Made by TI, probably in the mid to late 80s. I have many thousands of them, All NOS, in the TI packaging.... I asked TI, they were no help, I searched the web, nothing...

2021-04-14 21.22.57.jpg

2021-04-14 21.22.40.jpg

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7 hours ago, JohnR725 said:

Did the packaging have anything resembling any kind of numbers at all? Then was it just placed in a package or does it look like it actually came in the package?

It def is in the ti packaging but who knows if they belong there.  I have around 20 thousand of them.  The only other numbers on The packaging says SKB3843 and TI 741A also,  4 large boxes almost all of them are still sealed in individual packs of 500.  I would be happy to part with some if anyone wants some.

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34 minutes ago, CWRNH said:

I would be happy to part with some if anyone wants some

Put a couple in an envelope and send them to me.  I will see if I can figure out what they are.  1) do some simple curve tracing, 2) crack one open and (hopefully) take a look at the die.  I will send you a pm with my address.

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On 4/18/2021 at 9:19 PM, LittleWatchShop said:

Put a couple in an envelope and send them to me.  I will see if I can figure out what they are.  1) do some simple curve tracing, 2) crack one open and (hopefully) take a look at the die.  I will send you a pm with my address.

I will put some in the mail to you when you PM me your address.  Thank you.

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  • 2 weeks later...
On 4/7/2021 at 2:16 AM, xyzzy said:

Tg seems to be able to handle your sample just fine.  There is a lot of low frequency noise, but the 3kHz high-pass filter takes care of it well.  There is a big glitch on the paperstrip about every 22 seconds, because that is when the audio sample loops.  The smaller glich about 17 seconds sounds like muffled thumping, as one gets when the microphone or watch is being moved.

image.thumb.png.38015fab0fbe0cbe01f10c4603a20340.png

Here is a spectrogram.  We can see the ticks, as well as lots of noise in the < 2kHz range, as well as something at about 16 kHz.

image.png.866e4af48ab8cc1eb94fda5ff83f1be1.png

Here's a closeup of the < 3kHz noise.  Definitely something very large at about 710 Hz.  I'm not sure what is going on at 1.9k and 1.1k.  Maybe the microphone holder is vibrating on the watch?  It seems like the movement is causing something to resonate one of two frequencies for an entire beat or more.

image.png.2066516f362926af5f354af5c3821dad.png

What Spectrum analyzer are you using?

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1 minute ago, guidovelasquez said:

The results are amazing. The best indicator of microphone and preamp performance is what is indicated by the blue circle on the eTimer. We have a very high signal-to-noise ratio. 49dB. Nice job @CWRNH

172412895_SNRNOISE.thumb.jpg.588b4db971b7a7487b3dac245d521cf8.jpg

Thank you, What is the common?

 

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