11:21 PM
@Kellenjb Microphone starts producing signal when it's near WiFi antennas. Hissing, pops and a chopping sound can be heard when I listen to recorded sound.
@MicronXD The two grounds should be connected together. What type of transistor do you want to use? MOSFET would be easiest, since you'd just connect the gate to a output pin of the ATmega.
@MicronXD You could also connect a relatively high resistor (say 10k) between the gate and ground. It should allow the MOSFET to turn of faster.
@MicronXD If you have a bi-polar junction transistor, you'd have to connect the pin in series with a resistor which will limit the current going into the transistor. Use the datasheet to calculate the maximum base current and set the appropriate resistor on the line going from microcontroller to the base. If you want the transistor to turn off more quickly, then again put a large resistor between the base and the ground.