@freemo HOw many frequencies can it count?
@Surasanji right now up to 39Mhz at 3Vpp and 3.3 volt power supply. I have to improve this significantly still
@Surasanji Update, I just swapped out the diodes for a different brand and now I can get up to 55Mhz (my target) with a signal down to 700 Vpp, so just need to get that minimum signal voltage a bit better and she will be up to spec.
@freemo All you need is 52 hertz and you can talk to that one lonely whale. I can see nothing wrong with this line of thought.