Dreaming of building a Piezo Buffer
Breadingboarding the Piezo Buffer
How to test a JFET
Here's the underside of the perfboard.
When I powered the board up I had all the expected problems with bad solder. These were easy to fix. Eventually I got sound...
I was heart-broken to discover that the circuit was just as noisy on the perfboard as it is on the breadboard. NOOOOOOOOO! What on earth could be wrong? WHY ME????
After much thinking I began to wonder if perhaps the noise was due to my driving the JFET with too high a voltage. It was at this point that I dug out my Dying Battery Simulator. Ha ha! I just KNEW I'd get to use it sometime!
What you'll see in the above video is my discovery that reducing the supply voltage did in fact reduce the noise significantly. As it dropped below 8 volts the circuit started to behave itself to the point where I was doing hand-springs down the hall and high-fiving the dog.
I've since figured out the resistance required to achieve the voltage drop and added this to the perfboard.
I'd like to end on a high, but unfortunately, I can't in this instance. Although the noise has been significantly reduced, there is still a quiet but noticeable background hum being produced that is slowly destroying me. My next post will be about debugging. As I write, I'm all out of ideas. Wish me luck...