Hi Everyone,
This is a circuit I assembled about a month ago with the help of the members from this forum(Link, special thanks to "ericgibbs").
I recently took the oscilloscope to it and I was wondering weather anyone can explain to me what is going on.
compared to the signal from the piezo element (top), why is the gain stage from the IC is not steady and have a strange peak after the middle
I thought it's the negative peak from the piezo what's causing the problem, so I used a Shotky diode (Bat85) to ground the negative side but It seems to make the make the problem worse.
This strange peak seem to affect the LED from LM3914
any idea whats going on?