> > It sounds like you are asking for two different things. First you asked=
 for a
> > sonar transducer and then later a circuit.
>=20
> Well, I took it that the second was to drive the first.
>=20
> The electronics is fairly basic, a gated oscillator, and a receiver that
> then listens to the transducer a moment after the transmit ends. The
> receiver will normally have some form of AGC so it gets more sensitive
> over time to pick up the further away echos.
>=20
> You won't get a 360 degree transducer. The only way you would do this is
> to have multiple transducers. It would be useful to have individual
> receivers for each transducer.

Either way it's not going to be easy. Before designing any circuit, you
need to have the transducer problem figured out. If you can get a 360
degree transducer, it's going to take a whole lot more drive, and=20
amplifier signal/noise ratio is a problem because it will produce a lot
less echo signal than a 60 degree transducer. Using multiple 60 degree
transducers, each with its own receive preamp and discriminator, would
work nicely except you'd need 18 of them to give full coverage of a
sphere.

Friendly regards, Bob
=20

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