From a little internet
searching it appears similar systems have been available since about 2005 or so. The prices are competitive between four or five different manufacturers and not a small sum to someone like me.
Seems to me this device would be a sweeping frequency generator
and pulse width modulator at its core
. Combined with a sounder transducer that will accept a frequency typically less than a depth sounder
uses. Probably sweeps from maybe 25kHz to 100-200kHz triggered by square wave pulses of a few hundred milliseconds with varying off intervals between pulses. Simply beats the hull
with sound waves of very high frequency. How close is that?
What will distinguish your device from the competition? Could it be price
? I'm sure this device can be sold for less than others as it's not that that complicated of a circuit.
Have you considered hooking up with a Chinese manufacturer and West Marine
or Defender to mass produce and bring the price
down to about $200 dollars? That would create a market for yours and put the others out of business.
I have to wonder why West Marine
doesn't sell something like this already. Could it be that this idea hasn't been able to prove itself viable in the years it has been available? Maybe it doesn't work as well on boats as it does on aquariums and swimming pools.