So this is pretty much my first experience with any sort of electrical DIY aside from making cables. I wanted to make a simple pre-amp for electret capsules. I used this design: http://www.minidisc.org/mic_preamp/Simple%20Stereo%20Electret%20Mic%20Preamp.htm
It picks up sound from the mic but there's a fairly loud humming in the background. Here's a photo:
I expect it's grounding issues butI really have no idea what I'm doing. The blue wire coming off the opamp is from the VCC- leg but I don't know where to wire it to so it's going nowhere. The negative wire from the mic is going to the negative wire on the battery, the ground from the 3.5mm output is wired to the ground on the pot. It's probably a total mess. I'm actually very surprised that it works at all.
Can someone tell me what I'm doing wrong?
Edit: The hum can only be heard when I set my input to full gain.
Edited by fraseyboy - 4/21/14 at 4:07pm