I have set up a surveillance system with NVR, PoE switch and network cameras. For the audio in RCA female jack in NVR, I have extended one 12v dc power adapter and another RCA male to male cable to the spot on the ceiling where the microphone will be fixed. Now the microphone I bought online has 3 wires. How to connect 3.5 mm power jack and RCA jack?
The instructions or specs of the mic will tell you that.
Does the mic require a power supply at all?
A balanced output microphone would have a +, -, and ground wires. You would need an adapter to use it with an unbalanced RCA input.