Does anyone here know of any cheap-ish handheld meters that are capable of measuring the voltage at specific audio frequencies?
I'm dealing with a few constant frequency signals on the same wire - and would love to be able to tell the voltage at specific frequencies.
The answer below is a great answer - and I guess I should have clarified slightly in asking the original question.
The frequencies are specific frequencies: i.e. 1560 Hz, 1620 Hz, 1680 Hz, 1850 Hz
I have thought of using a scopemeter with fft support, but haven't though of using a microcontroller with fft! I'll have to look into that.
I've also looked into using bandpass filters, but the frequencies are so close together that the orders would be crazy high.