I am trying to use a piezo as a speaker.
(I know that a piezo has a bad frequency-response. However, In my application it is better to use one instead of a speaker, since normal speakers don't like to be covered in gel.)
Since a piezo is so much softer than a normal speaker, I want to amplify the signal. After looking for some tutorials on the internet, I found that i should be possible to use an Op-Amp connected in the Non-inverting Amplifier way. I bought a LM324 Op-Amp to use in this circuit. The 2.5mm jack is the plug that is used in most computer headphones.
Here is my curcuit, as connected on my protoboard:
This does not seem to do any amplification of the signal. So I must have connected something wrong, or maybe my understanding of the different parts involved is incorrect. I hope someone can point the problem out.