ted:
You can adopt TV remote control, you need to lower transmitting frequency, divide it by 2 ,so will fit in audio range.
the depth will be under 5m - however the distance could be the size of a small lake - say 300m Max
ted:
You can adopt TV remote control, you need to lower transmitting frequency, divide it by 2 ,so will fit in audio range.
the depth will be under 5m - however the distance could be the size of a small lake - say 300m Max