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9 hours ago, svorkoetter said:

You quoted my entire original post from 6 years ago, pictures and all, to add this (incorrect) bit of information?!? Hint: I've been a professional software developer for 31 years.

https://lmgtfy.com/?q=featuritis

 

9 hours ago, svorkoetter said:

You quoted my entire original post from 6 years ago, pictures and all, to add this (incorrect) bit of information?!? Hint: I've been a professional software developer for 31 years.

https://lmgtfy.com/?q=featuritis

That’s a coincidence I am a electronics engineer (retired) and we used this all the time especially if we had equipment trials going back some 40 years

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Hi good day to you I have a vibrograph B200 and I need to repair the microphone the element has disintegrated with age this timer I have had since about 1969 70 the timer still works well and it is just the microphone needing repairs or replacing.  Is it possible to purchase the parts or a complete microphone from you?

Kind regards

Mannetjie  

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Good day Svorkoetter   I have a Vibrograf B200 and the element in the microphone has disintegrated with age I have had this timer since 1969-70 the timer is still perfect only the microphone is not working anymore   Will it be possible to use your microphone on my Vibrograf timer and if so what would it cost for a microphone or would I be able to purchase the parts and assemble it myself The reason I ask is that I live in South Africa Kind regards Mannetjie 

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I think the Vibrograf B200 Microphone might have a little more space in it. Then whatever I saw somebody had used a piezo disc and they do come in a variety of sizes.

Then because the originals are water-soluble I'm reasonably sure that they're made of Rochelle salt (sodium potassium tartrate tetrahydrate) It's amazing what you can find on Wikipedia.  So what will happen with time is They will absorb moisture and just disintegrate.

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  • 8 months later...
On 3/17/2017 at 6:45 PM, cuevobat said:

As a sign of just how crazy this is getting I went out an bought a Windows PC to run WatchOScope. 

Hello everyone.   I signed up for these forums after finding this very interesting thread.  

You don't need any kind of whiz-bang PC to run this software.  Any old PC, even one several generations out of date, will do nicely.   Where I live (New Jersey) electronic junk must be recycled by law, it can't go in the trash.   I've picked dozens of old PCs out of the recycling bin at the DPW.  Most are still working, or I've put together PCs using parts from several scrapped machines.   Working keyboards, mice and other stuff all free for the taking.  Most of the flat panel monitors don't work, but most can be put back into service for the cost of a hand full of electrolytic caps.    

As a result, I've got several machines dedicated to running hobby software.   One machine in the garage to run auto repair software, another in the basement to run some other hobby software.   All it was free, or nearly free.  This is also a very productive time of year for dumpster diving.   People got new toys and are throwing the old stuff out, almost always in working condition.   I'm typing this on a machine I put together entirely out of scrapped parts.  

For my next project, I'm going to see if I can't get this software/DIY hardware to work for me. 

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9 hours ago, Fissile said:

Congratulations.
You live in what I would consider "the paradise of technology" And your story is very interesting. I think I would be doing the same as you. However, in my country things are a little different. The things that people collect in the garbage in your country, people with business intelligence import them into our country and sell them to us. However, in those places, I have found incredible things. functional. I will give you an example. I have purchased several radio controlled wall clocks. That most of the people in my city don't know how to use. Working in perfect condition. As you say. They buy new toys and throw the old, but functional and in good condition, in the trash.

 

Edited by guidovelasquez
Error de traducción.
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17 hours ago, Fissile said:

You don't need any kind of whiz-bang PC to run this software.  Any old PC, even one several generations out of date, will do nicely. 

?
Same is valid for PCTM software.

Using old but able hardware is not only low cost/free but also is good for our environment.

Frank

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  • 3 weeks later...
On 3/26/2015 at 6:35 AM, JohnR725 said:

So install the software on a netbook which has a minor problem of the screen is too small and toolbar on the bottom covers up the very bottom of the screen. I think there’s a way of making the toolbar disappear I just haven’t had time to look into that. So left everything on default other than changing the lift angle for the particular watch I was timing. So outstanding that the software is out to play with.

 

Then there have been other Windows-based timing machines in the past none of which worked very well so I made this amplifier to play with the other software. So this is a dual op amp design with a little bit of filtering.

post-673-0-95631200-1427366014_thumb.jpg

post-673-0-34102100-1427366015_thumb.jpg

post-673-0-83581800-1427366015_thumb.jpg

Can you share the schematic for the preamp with me or show me where to find it?

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7 hours ago, CWRNH said:

Can you share the schematic for the preamp with me or show me where to find it?

I may be wrong but I think somewhere in the 30 pages it may be buried. But there is also this one that you could build At the link below. Then if you can't find the schematic and the 30 pages I can dig it out because I was going to do that anyway sometime this year. A combination of things have changed in that that circuit board was to test out a idea. I now have a much better way to make circuit boards I was thinking of shrinking it. But I have other projects first so as not to happen instantly unless you need the schematic and I'll see if I can figure out where it went to do it's not in the group someplace. Or for some unknown reason you don't want to make the one at the link below which is also in the discussion group also somewhere.

http://www.watchoscope.com/amplifier.html

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Thank you, I did go through the whole 30 pages a few times, I saw a hand written drawing of your idea but couldn't read all the values.  I may have missed another.  I don't need to build it right away, I am using a modified board out of a microset for the time being and have other machines.  I just wanted to make my own.  I do have the watchoscope software and the e-timer software, my setup works well but is large.  I look forward to seeing any info you share in the future.  Thanks again.

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I can't find it now but on one of the forums, somebody posted a very simple set up.  One transistor, one resistor, a plug and a piezo disc.  This person got it all to fit in the plug end.  I know nothing about electronics and I built one.  Two actually.  I had to wire in headphones to make the Mac work.  I read somewhere that a Mac won't turn on the mic unless headphones were plugged in too.  Works on my Win10 machine with just the mic wired up. I bought a 10 pack of transistors, a pack of 1M ohm restistors, piezo discs, and TRRS plugs with a pigtail. 

With the headphone, I could hear a very clear and clean tick-tock.  I'm using the open source TG app.  I get a good clean signal on it.  I just can't get TG to run well on the Mac, that's a battle for another day.  Better signal than any headset microphone I tried before.  Messing with the sound card equalizer gave an even better signal. 

I'll dig up my notes and post them when I find them. 

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2 hours ago, bklake said:

I can't find it now but on one of the forums, somebody posted a very simple set up.  One transistor, one resistor, a plug and a piezo disc. 

There is quite a few pages in this section, all sorts of ideas for amplifiers have been posted including what you're describing. For instance page 17 towards the bottom you'll find what you seek.

https://www.watchrepairtalk.com/topic/3002-d-i-y-watch-timing-machine/page/17/

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2 hours ago, bklake said:

I can't find it now but on one of the forums, somebody posted a very simple set up.  One transistor, one resistor, a plug and a piezo disc.  This person got it all to fit in the plug end.  I know nothing about electronics and I built one.  Two actually.  I had to wire in headphones to make the Mac work.  I read somewhere that a Mac won't turn on the mic unless headphones were plugged in too.  Works on my Win10 machine with just the mic wired up. I bought a 10 pack of transistors, a pack of 1M ohm restistors, piezo discs, and TRRS plugs with a pigtail. 

With the headphone, I could hear a very clear and clean tick-tock.  I'm using the open source TG app.  I get a good clean signal on it.  I just can't get TG to run well on the Mac, that's a battle for another day.  Better signal than any headset microphone I tried before.  Messing with the sound card equalizer gave an even better signal. 

I'll dig up my notes and post them when I find them. 

https://www.instagram.com/p/B-oAzLGFff3/?utm_source=ig_web_copy_link

 

https://www.watchuseek.com/threads/simple-and-effective-homemade-microphone-stand-for-watch-timing-apps-timegrapher.5135031/

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Thanks for bailing me out.  I had to go do real work for awhile so couldn't look. 

The diagram I used showed a 1M ohm resistor (Watchuseek link?) and had a wiring diagram for a TRRS plug.  Apple swaps the Mic and Ground.  The transistor is a BC549b not BC5498.  The B looks like an 8 in the grainy pdf. 

I am an electronics caveman so if I can do it everybody should be able to. 

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On 2/17/2015 at 12:33 PM, svorkoetter said:

 

Sure. First the schematic:

 

post-140-0-62257500-1424197452_thumb.png

 

There is only a single chip, a TL074 quad op-amp. R7 is a trimpot, since you really should only need to set it once, but you can use a panel-mounted pot if you want. Just be sure to use shielded cable from the board to the panel.

 

The main differences between this circuit and my previous one are that this one uses a stabilized and filtered virtual ground in an effort at further hum rejection, and it uses three stages of amplification instead of two. There's also more high-pass filtering, but at a lower cut-off, so hum rejection from that should be about the same, while allowing more low-end sound from the watch through.

 

Here's the circuit board component layout, as viewed from the component side:

 

post-140-0-61927600-1424197477_thumb.png

 

And circuit board artwork, as viewed from the copper side:

 

post-140-0-20276500-1424197552_thumb.png

 

Note that I have built two of these. C1 was originally omitted, so it won't appear in the photos I posted earlier, so technically I have not built this latest version which adds C1 to the board layout, but I did retrofit C1 onto the existing boards.

 

EDIT: The locations for C2, C4, and C6 have three holes each, to allow use of capacitors with either 0.1" or 0.2" lead spacing. If using the former, be sure to use the correct pair of holes.

Nice work!  Those look like band-pass stages to me.

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1 hour ago, bklake said:

I bought some 2N3909 transistors awhile ago.  Which one is better, the 2N3904 or the BC549b?  I tried to read the spec sheets and was lost 3 words into it.  The wire up the same way. 

https://es.wikipedia.org/wiki/2N3904

I think that the 3904 is the most suitable option. As I have seen, it can even be found in many devices, if it were not possible to get it new in a store.

 

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Thanks John for searching the circuit in this loooong thread!

Some notes on my simple but proven 1-transistor design:

Which transistor depends on your location: BC 549 (a low noise type btw) is more  popular in Europe, 2N3904 in US. Generally a transistor produces much less noise than any OP-amplifier.

Some mic inputs (4-pole plugs) are quite touchy with switching to the external mic.  Though a lower resistor gives slightly higher amplification, it showed that a 1 M resistor  gives best performance (switching most inputs). But if you build for your own use, you can try which works best (~ 330 k ... 1 M).

Frank

image.png.59b54eb5e92f855e72e77e136d4136da.png

Link to PCTM

Edited by praezis
edited schematic
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Finished roughing out my All in one Timing machine.  It works very well.  Now I will do the paint and engrave the faceplates.

Windows 10 micro pc, 10in touch screen, using microset, watch-o-scope, and e-timer software, has an oscilloscope and multimeter also that connect to the preamp out port and the USB.  Has Removeable speaker for hearing tick sound (connects to preamp out port)

Headphone jack

Preamp out

Temp sensor input

Pickup (Mic) input

USB port

Very sensitive pickup on a multi-directional base that I made years ago.  Can get a clean signal from even the smallest movements easily.  Has noise canceling with adjustable blanking, and gain. 

Signal is acquired from a Preamp made from a modified microset board and pickup.  Connects to internal PC via a USB soundcard and a serial port.  

Machine has no ground externally a uses battery to separate the preamp from the computer and main power.  Everything is shielded and grounded internally and has RF and EMF reducing like Ferrite Toroids / Ferrite Rings...

 

2021-01-16 12.30.45.jpg

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  • 3 weeks later...
On 10/22/2016 at 5:31 PM, wlysenko said:

My previous attempts to lower noise in the preamp were flawed because I changed the bandwidth in doing so. The following circuit fixes this. There is an added buffer stage that uses an LT1115 op amp to isolate the microphone from the first amplification stage. Now the high-pass filter on the first stage does not depend on the capacitance of the microphone. I have it set for a frequency of 800 Hz (according to Stefan's comment of 800 Hz to 8 kHz being a good passband). I did not change the other high-pass filters to 800 Hz, but maybe I should have. The low-pass filters are all at 11 kHz, just as in the original Watch-O-Scope design.

I built the circuit on my solderless breadboard. The measured noise was 6 mV, which should be compared to the 22 mV of the original circuit. I had a lot of trouble getting a buffer that was stable. I could not get the NE5534 op amp to work for this. It insisted on oscillating, even when I added the recommended 22 pF compensating capacitor across pins 5 and 8. My present circuit is still not perfect. It oscillates when the microphone (or signal generator) is unplugged from the input.

four-stage-amp.jpg

"0.1 Bypass caps on buffer stage lower pins"  Could you or anyone else please explain this to me?  I have everything done to this point and just need to know where these bypass caps connect....

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