The board I use for tachometers, speedometers, wheel speed sensors, and that sort of thing is basically an AC coupled cap in series with the input that is filtered and sometimes amplified, sent through a diode and then counted. This works for millivolts pure AC and it works for 0-12vdc square waves, and lots inbetween. For instance the tach signal I generally take right off of the coil so it gets 200v spikes along with the "normal" edge.
That's good! A "universal" input (frequency) board and no need to worry about spikes, DC offsets, etc.
IMO well done. Another great FB product!
I haven't made it public yet, but I suppose I could. It works nicely! :)
Originally Posted by OldSpark