Building a piezo pre-amp using TL072 - Video one (testing)
I'm making a piezo microphone preamp using a TL072, as well as one for comparison using an NE5534.The MPF102 amp which I made recently wasn't all I expected, this is already much better, I want to make an amp which has variable gain, as well as possibly variable impedance and attenuation.
I made the PCB's based other peoples schematics, if you want to see them you'll have to go to their sites, they can be found at;
NE5534;
http://www.richardmudhar.com/piezo-contact-microphone-hi-z-amplifier-low-noise-version/
TL072;
https://andymurkin.wordpress.com/2017/11/25/piezos-pt-2-contact-microphones/
Most people would have bread-boarded the first stage, but I made these complete in order to get a decent expectation of what already existed, these do work pretty well, but they don't do exactly what I am after, so this is a start point for me. From here I'll go into breadboard prototyping in order to optimize the TL072 design.
I intend to develop the TL072 as a SMD board (I may move to the NE5532), The NE5534 design is so that I have something to compare my efforts to, but it's expensive, and I haven't been able to find a SMD package which the TL072 and NE5532 offer.
I have made a video on how I made the PCB's, which can be found here;
https://www.youtube.com/watch?v=U46iWRBSlgk
Ii intend to make seperate videos on the making of the piezo microphones as well as each stage of the optimization of the design, up to making an actual product (which will be open source). I will link those videos here as they are done.
The NE5534 works much better than the TL072 right now, but I'm optimistic that i can optimize the design of the TL072 to come close or match it.
I also have blog posts on this;
Making PCB's;
https://secretivesquirrel.wordpress.com/2018/12/29/pcb-etching-with-photosensitive-dry-film-now-working-consistently/
The blog post for this video is to come, I tend to make the video first - I'll update this when it's done.
This is definitely my last video for 2018, it's 11PM on New years Eve - Happy New Years :)
I made the PCB's based other peoples schematics, if you want to see them you'll have to go to their sites, they can be found at;
NE5534;
http://www.richardmudhar.com/piezo-contact-microphone-hi-z-amplifier-low-noise-version/
TL072;
https://andymurkin.wordpress.com/2017/11/25/piezos-pt-2-contact-microphones/
Most people would have bread-boarded the first stage, but I made these complete in order to get a decent expectation of what already existed, these do work pretty well, but they don't do exactly what I am after, so this is a start point for me. From here I'll go into breadboard prototyping in order to optimize the TL072 design.
I intend to develop the TL072 as a SMD board (I may move to the NE5532), The NE5534 design is so that I have something to compare my efforts to, but it's expensive, and I haven't been able to find a SMD package which the TL072 and NE5532 offer.
I have made a video on how I made the PCB's, which can be found here;
https://www.youtube.com/watch?v=U46iWRBSlgk
Ii intend to make seperate videos on the making of the piezo microphones as well as each stage of the optimization of the design, up to making an actual product (which will be open source). I will link those videos here as they are done.
The NE5534 works much better than the TL072 right now, but I'm optimistic that i can optimize the design of the TL072 to come close or match it.
I also have blog posts on this;
Making PCB's;
https://secretivesquirrel.wordpress.com/2018/12/29/pcb-etching-with-photosensitive-dry-film-now-working-consistently/
The blog post for this video is to come, I tend to make the video first - I'll update this when it's done.
This is definitely my last video for 2018, it's 11PM on New years Eve - Happy New Years :)