Robot ear
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Posts: 46,084
Hello all! I'm trying to create a circuit that will tell me
specifically what DIRECTION a sound wave above a particular
volume level is coming from.
In my mind, I picture 8 mics and 8 386 style power amps with
flickering leds next to each microphone.
This present idea would use up 8 stamp I/O lines. (Polling
being out of the question - consider the physics).
If anybody has a better (read cheaper) idea that would also
allow the use of condenser-syle mics, please let me know.
NOTE:
I'm a bit of an amateur and have no idea how to proceed
with converting the amplifier outputs into digital i/o lines.
the 386 op amp is the only chip I even HAVE a schematic for.
specifically what DIRECTION a sound wave above a particular
volume level is coming from.
In my mind, I picture 8 mics and 8 386 style power amps with
flickering leds next to each microphone.
This present idea would use up 8 stamp I/O lines. (Polling
being out of the question - consider the physics).
If anybody has a better (read cheaper) idea that would also
allow the use of condenser-syle mics, please let me know.
NOTE:
I'm a bit of an amateur and have no idea how to proceed
with converting the amplifier outputs into digital i/o lines.
the 386 op amp is the only chip I even HAVE a schematic for.
Comments
decoding circuit... something like an orthogonal dual loop antenna radio
direction-finder setup. This is just speculation, mind you, but I don't see
why it wouldn't work...
>Hello all! I'm trying to create a circuit that will tell me
>specifically what DIRECTION a sound wave above a particular
>volume level is coming from.
>
>In my mind, I picture 8 mics and 8 386 style power amps with
>flickering leds next to each microphone.
>
>This present idea would use up 8 stamp I/O lines. (Polling
>being out of the question - consider the physics).
>If anybody has a better (read cheaper) idea that would also
>allow the use of condenser-syle mics, please let me know.
>
>NOTE:
>I'm a bit of an amateur and have no idea how to proceed
>with converting the amplifier outputs into digital i/o lines.
>the 386 op amp is the only chip I even HAVE a schematic for.
Mike Hardwick, for Decade Engineering -- <http://www.decadenet.com>
Manufacturer of the famous BOB-II Serial Video Text Display Module!
-ish. boy I'm dating myself here. 8^] Anyrate it directionalized sound by
using three microphones and measuring the phase difference. This was with
the capture/compare on a 68HC11, and I don't think the stamp is fast
enough. Bet you could do it with a 20mHz PIC though, especially if you
situated the mics far enough apart...just a thot.
Duncan
Thank you.
Memorial United Methodist Church
umc@i...
you get on the list in the first place?
-William
Original Message
From: Memorial Methodist Church <umc@i...>
To: <basicstamps@egroups.com>
Sent: Tuesday, June 20, 2000 2:51 PM
Subject: Re: [noparse][[/noparse]basicstamps] Robot ear
> Please remove us from your list.
>
> Thank you.
>
> Memorial United Methodist Church
> umc@i...
>
>
>
>
Thank you for your reply... But...
I'd like to know more about what you
suggested... Like... What the heck it meant.
--- In basicstamps@egroups.com, Mike Hardwick <decade@w...> wrote:
> How about using a pair of bidirectional (ribbon?) mikes with a
quadrature
> decoding circuit... something like an orthogonal dual loop antenna
radio
> direction-finder setup. This is just speculation, mind you, but I
don't see
> why it wouldn't work...
>
> >Hello all! I'm trying to create a circuit that will tell me
> >specifically what DIRECTION a sound wave above a particular
> >volume level is coming from.
> >
> >In my mind, I picture 8 mics and 8 386 style power amps with
> >flickering leds next to each microphone.
> >
> >This present idea would use up 8 stamp I/O lines. (Polling
> >being out of the question - consider the physics).
> >If anybody has a better (read cheaper) idea that would also
> >allow the use of condenser-syle mics, please let me know.
> >
> >NOTE:
> >I'm a bit of an amateur and have no idea how to proceed
> >with converting the amplifier outputs into digital i/o lines.
> >the 386 op amp is the only chip I even HAVE a schematic for.
>
> Mike Hardwick, for Decade Engineering -- <http://www.decadenet.com>
> Manufacturer of the famous BOB-II Serial Video Text Display Module!
Radio direction finders (RDF) were built as early as the forties, maybe
earlier, using a pair of circular loop antennas, one inside the other, with
the planes of the loops perpendicular. The antenna assembly looks a bit
like an inverted kitchen mixer attachment. Relative direction of an
incoming signal may be determined unambiguously by decoding its phase in a
circuit that I don't recall. Perhaps someone else can help out, or you may
be able to find it in the amateur radio literature (hams do transmitter
hunts for sport).
What I'm suggesting is this: Set up a pair of bidirectional mikes with 90
degrees offset in the horizontal plane, or try four conventional mikes with
opposite-facing pairs combined out of phase, to get a pair of signals that
mimic the old RDF antenna. Then build up a phase decoding circuit similar
to the old RDF circuit, but re-tuned for audio frequencies. The output
*should* be a precise direction signal, unless I've overlooked something
fundamental here.
>I'd like to know more about what you
>suggested... Like... What the heck it meant.
>
>--- In basicstamps@egroups.com, Mike Hardwick <decade@w...> wrote:
>> How about using a pair of bidirectional (ribbon?) mikes with a
>quadrature
>> decoding circuit... something like an orthogonal dual loop antenna
>radio
>> direction-finder setup.
Mike Hardwick, for Decade Engineering -- <http://www.decadenet.com>
Manufacturer of the famous BOB-II Serial Video Text Display Module!