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Discussion Starter #1 (Edited)
Any users willing to post some DIY for their piezo transducer and preamp?

any advise appreciated, there just doesnt seem to be much info floating around... errr or at least in something besides japanese

I have an ocilliscope and function generator if needed for calibration.

BIBURO (freeware, right click then "save as")

or maybe some DIY methods using an o-scope directly with a piezo pickup

TIA,
Av
 

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Discussion Starter #3 (Edited)
watchmag,

Thanks for the print, that's easy enough. I was thinking maybe a 741 op-amp (IIRC)...

How well does the system work for ya? Do you see the need for any low pass and high pass filtering? I have found a couple refs concerning their need. I see the print is calling for sheilded cable.

I did have my Industrial CET journeymans license once upon a time but that was over 20 yrs ago so I'm very, very "rusty".

TIA,
Av
 

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741 is much too noisy and low impedance for this. I use a cut down guitar pickup and a transistor circuit with a FET front end. Let me know your address, and I'll send you a sketch. Meanwhile, I'd like to try Biburo but I can't make it work here in the UK. Update: your link worked and it looks like a good program. I wonder what to do about the reference oscillator for calibration. (PCs are useless at this). Out with the felt tip pen then (I'm hopeless at drawing on the computer!)
 

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Using a 'scope is not really an option unless you are using a modern DSO . The timebase is simply not accurate enough. The usual approach is to use a crystal derived square wave, triggered off the tick but it is somewhat hit and miss. There is a good circuit for a piezo pickup preamp here,

www.scotthelmke.com/Mint-box-buffer.html

and plundering this will take you most of the way. A simple audio preamp kit with a gain of 10-100 from your local hobby electronics vendor should pump that up to your computer's input level.

Hint: build it in a well screened box. Piezo transducers and their amplifiers are so noise sensitive that mains hum on the signal will throw the timing right out. How do I know? Lots of prototypes!
 

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Discussion Starter #6
outstanding!!

Ill PM you my addy, and TIA

b-)
Av
 

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Discussion Starter #9
excellent, very informational thread :)
 

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Any users willing to post some DIY for their piezo transducer and preamp?

any advise appreciated, there just doesnt seem to be much info floating around... errr or at least in something besides japanese

I have an ocilliscope and function generator if needed for calibration.

BIBURO (freeware, right click then "save as")

or maybe some DIY methods using an o-scope directly with a piezo pickup

TIA,
Av
The site and ZIP file are inaccessible :-s
Anyone want to e-mail me the file?
 

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Discussion Starter #11 (Edited)
AG,

Dont try to go to the link, just right click on it and "save as" and dont use any type of downloader accelerator... I just verified link is still working,

If you try to go to the url it wont allow you, all you will get is a 403 error

in any case, if you need it emailed to ya just PM me the addy... Ive got it saved on my HD

Cheers'
Av

EDIT: Here ya go, I posted it on geocities for ya BIBURO
 

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AG,

Dont try to go to the link, just right click on it and "save as" and dont use any type of downloader accelerator... I just verified link is still working,

If you try to go to the url it wont allow you, all you will get is a 403 error

in any case, if you need it emailed to ya just PM me the addy... Ive got it saved on my HD

Cheers'
Av

EDIT: Here ya go, I posted it on geocities for ya BIBURO
Thanks a bunch :-!
 

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I'm not getting anywhere fast with this. The mic input of the computer
is pretty hopeless and my preamp doesn't work at all well. even a signal generator fails to work as I would expect. With regard to the computer btw, It has been said that nobody ever got fired for recommending IBM. Another first for PC Pro whose subscription I'll not be renewing. The Lenovo SL500 really sucks. The mobile broadband took a fortnight to get set up and then didn't work at all well, Wifi connects just fine as long as you are within six feet of the router and the backup to DVD utility burnt all my photos to discs that lock up the machine when inserted. It is now five weeks old and after wasting two days on the 'phone to Lenovo/Vodafone and the suppliers, I've had enough of the damn' thing. Tomorrow it will meet the radial arm saw. £500 wasted, be warned. Wish I'd wasted it on a nice old Omega instead.
 

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Discussion Starter #16
Watchmag,

It will be a month or so before I can devote any serious time to the project. I still have yet to build the piezo transducer and pre-amp. With the great info provided I dont forsee much problem.... err I hope LOL

Av
 
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