AVR-Chat

My bottom sounder will be using transducers for the high freq. Also a forward looking 'sound' object avoidance, other boats (motor sound), will be a waterproof mic. I am learning while 'playing'. I could ask someone for the answer to make it work but that is no fun. Just looking for ideas to get me in the right direction.

Brian

--- In AVR-Chat@yahoogroups.com, "Dave McLaughlin" <dave_mclaughlin@...> wrote:
>
> Actually, if this is mapping and you only need the first solid return, a
> simple echosounder will do this for you.
> 
> Just measuring sound is not going to work as you could potentially be
> picking up sound from all directions.
> 
> Sonar and echo sounders use a narrow beam which is pulsed on and off and you
> listen for the return. The intensity of the reflection and time is used in
> sonar. For echo sounder you simply listen for a reply above a preset level.
> The frequency at which you transmit also determines the level of the return.
> I worked in the North Sea with a 500Khz echo sounder and in one location we
> got hardly any returns from the soft silty seabed. The 1Mhz scanning echo
> sounder got great returns.
> 
> How is you mapping idea going to work?
> 
> Dave...
> 
> -----Original Message-----
> From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf
> Of Jim Wagner
> Sent: 25 August 2011 09:53
> To: AVR-Chat@yahoogroups.com
> Subject: Re: [AVR-Chat] Re: sound measurement
> 
> If you are "mapping", then you are probably talking about sonar, which
> requires a transmitter and receiver, and a measured time delay for the echo.
> This is very different from just measuring "sound amplitude".
> 
> Jim Wagner
> Oregon Research Electronics
> 
> On Aug 24, 2011, at 6:58 PM, blue_eagle wrote:
> 
> > I wanted to try audio range and up to about 125KHz range. This is for 
> > lake mapping. I could buy one but just want to make one and learn at 
> > the same time.
> >
> > Brian
> >
> > --- In AVR-Chat@yahoogroups.com, Jim Wagner <wagnerj@> wrote:
> > >
> > > What frequency range?
> > >
> > > Jim Wagner
> > >
> > > On Aug 20, 2011, at 8:05 PM, blue_eagle wrote:
> > >
> > > > I havent picked an avr chip yet. What I want to do is measure the 
> > > > sound underwater from two microphones to find out which one has
> > more
> > > > sound over the other. Trying to understand how to use the micro to 
> > > > average sound inputs. How often should it sample? Do you have a 
> > > > website to explaine it?
> > > >
> > > > Thanks,
> > > > Brian
> > > >
> > > >
> > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
> > 
> 
> 
> 
> [Non-text portions of this message have been removed]
> 
> 
> 
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