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2011-08-21 by blue_eagle
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
2011-08-21 by Jim Wagner
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]
2011-08-24 by blue_eagle
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] >
2011-08-25 by Jim Wagner
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]
2011-08-25 by Dave McLaughlin
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] ------------------------------------ Yahoo! Groups Links ----- No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1392 / Virus Database: 1520/3855 - Release Date: 08/24/11
2011-08-25 by blue_eagle
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] > > > > ------------------------------------ > > Yahoo! Groups Links > > > > > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 10.0.1392 / Virus Database: 1520/3855 - Release Date: 08/24/11 >
2011-08-26 by bobgardner@aol.com
Drag two hydrophones behind the boat. Use an a/d chip that does simultaneous sampling. A prop approaching from 45 deg to starboard has its chugchugchug waveform reaching the front mic before the rear mic (shorter radial distance). I guess you need to drag two more hydrophones abeam from poles to tell if the noise is coming from port or starboard. [Non-text portions of this message have been removed]
2011-08-27 by blue_eagle
I have spent 4 1/2 years on a US Navy submarine. I know how it is done. I just have to figure out how to do it in small scale. soft bottom and close distance. this is a problem. --- In AVR-Chat@yahoogroups.com, "bobgardner@..." <BobGardner@...> wrote:
> > Drag two hydrophones behind the boat. Use an a/d chip that does simultaneous sampling. A prop approaching from 45 deg to starboard has its chugchugchug waveform reaching the front mic before the rear mic (shorter radial distance). I guess you need to drag two more hydrophones abeam from poles to tell if the noise is coming from port or starboard. > > > > > > > > > [Non-text portions of this message have been removed] >
2011-08-29 by blue_eagle
I have two micro waterproof microphones coming in tuesday to play with. I plan on testing them in my 15 foot pool. Problem is echoes off of the sides and bottom, way different than a lake but somewhere to start. Brian --- In AVR-Chat@yahoogroups.com, "blue_eagle" <blue_eagle74@...> 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 >