Hi. My name is Dušan Halický and here are few of my electronic projects. You can contact me on my email dusan.halicky@gmail.com. This page is also available as RSS feed.

Piezo preamp

My first SMD board!

Simple JFET (or MOSFET) source follower to handle piezoelectric disk pickups, with simple NPN emitter follower to handle low impedance output down to 1700 ohm (e.g. input impedance of my soundcard's microphone input). Low distortion and noise. Powered from 9V battery it consumes only 700uA. It has the same size as 27mm piezo disk and you can solder it directly onto the board via 3 grounding holes and take output from hole in the center of the disk. KiCad project contains schematic and PCB. Gerbers can be directly uploaded to JLCPCB and you can have five PCBs manufactured for less than $5. Here is schematic and photo of finished PCB.