I've designed an amplifier to receive ELF-VLF (3hz to 30Khz) signals through a loop antenna and want to connect it to Sound Card mic input to analyze received signal.
The problem is that the maximum output of the circuit sould be limited to protect sound card from damages and avoid cutoffs in waveform because of saturation to prevent data loss.
I'm going to use Mic input over laptop and it should not be confused with Line In.
What is the maximum and nominal voltage values for microphone input? How much is the input impedance of Mic jack?
**Edit: ** It's going to be introduced to a group of enthusiast people with limited knowledge about electronics and it's definitely NOT a precise solution but a cheap and easy-to-use one. The aim is to keep it simple and safe. So please do not think of limited frequency response of sound cards or the exact maximum voltage suitable for every specific card. Just a safe voltage range should be enough.