microphone input to stamp
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Posts: 46,084
hi sorry to post this, searched the archives, but couldn't find or
quite figure out the information i wanted.
does anyone know how use a microphone for input to the basic stamp? i
want to make a sound level meter that dims or lights an LED
correspondingly.
1. do i need an op-amp?
2. do i need an a/d convertor?
3. anyone have a sample schematic?
thanks a bunch! (i'm new to the list!!)
\
-katherine
quite figure out the information i wanted.
does anyone know how use a microphone for input to the basic stamp? i
want to make a sound level meter that dims or lights an LED
correspondingly.
1. do i need an op-amp?
2. do i need an a/d convertor?
3. anyone have a sample schematic?
thanks a bunch! (i'm new to the list!!)
\
-katherine
Comments
have more planned.. Otherwise, considerable amount of engineering needs
to be done and that would probably include at least some of the items
you specified. Do you really want to 'dim' an LED or just turn it on &
off?
Leroy
kakirine wrote:
>
> hi sorry to post this, searched the archives, but couldn't find or
> quite figure out the information i wanted.
>
> does anyone know how use a microphone for input to the basic stamp? i
> want to make a sound level meter that dims or lights an LED
> correspondingly.
>
> 1. do i need an op-amp?
> 2. do i need an a/d convertor?
> 3. anyone have a sample schematic?
>
> thanks a bunch! (i'm new to the list!!)
> \
> -katherine
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
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of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
naive here?:-)
what i was thinking of trying is to control the brightness of an LED
based on the breathing patterns of an individual. there is more to
the idea, but that's the basics of what i need to get done.
thanks!
-k
--- In basicstamps@y..., Leroy Hall <leroy@f...> wrote:
> There are a lot of cheaper ways to that with out a stamp, unless you
> have more planned.. Otherwise, considerable amount of engineering
needs
> to be done and that would probably include at least some of the
items
> you specified. Do you really want to 'dim' an LED or just turn it
on &
> off?
>
> Leroy
>
> kakirine wrote:
> >
> > hi sorry to post this, searched the archives, but couldn't find or
> > quite figure out the information i wanted.
> >
> > does anyone know how use a microphone for input to the basic
stamp? i
> > want to make a sound level meter that dims or lights an LED
> > correspondingly.
> >
> > 1. do i need an op-amp?
> > 2. do i need an a/d convertor?
> > 3. anyone have a sample schematic?
> >
> > thanks a bunch! (i'm new to the list!!)
> > \
> > -katherine
> >
search for this would probably get you several hits. Stick the word
'application' & 'lm386' in the search term. It is sensitive enough to
be feed by a x-tal microphone and powerful enough to drive an LED. I
don't see a need for a stamp in the process..
Leroy
kakirine wrote:
>
> well... yeah, i really want to 'dim' the LED (am i being hopelessly
> naive here?:-)
>
> what i was thinking of trying is to control the brightness of an LED
> based on the breathing patterns of an individual. there is more to
> the idea, but that's the basics of what i need to get done.
>
> thanks!
> -k
>
> --- In basicstamps@y..., Leroy Hall <leroy@f...> wrote:
> > There are a lot of cheaper ways to that with out a stamp, unless you
> > have more planned.. Otherwise, considerable amount of engineering
> needs
> > to be done and that would probably include at least some of the
> items
> > you specified. Do you really want to 'dim' an LED or just turn it
> on &
> > off?
> >
> > Leroy
> >
> > kakirine wrote:
> > >
> > > hi sorry to post this, searched the archives, but couldn't find or
> > > quite figure out the information i wanted.
> > >
> > > does anyone know how use a microphone for input to the basic
> stamp? i
> > > want to make a sound level meter that dims or lights an LED
> > > correspondingly.
> > >
> > > 1. do i need an op-amp?
> > > 2. do i need an a/d convertor?
> > > 3. anyone have a sample schematic?
> > >
> > > thanks a bunch! (i'm new to the list!!)
> > > \
> > > -katherine
> > >
>
> To UNSUBSCRIBE, just send mail to:
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of the message will be ignored.
>
>
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>naive here?:-)
>
>what i was thinking of trying is to control the brightness of an LED
>based on the breathing patterns of an individual. there is more to
>the idea, but that's the basics of what i need to get done.
>
>thanks!
>-k
Would there be other options for sensing, say, the heat of the
breath, or motion or distortion of the chest? Where where you going
to put the microphone? Was it to be attached to the chest, or by the
mouth, or in some kind of fixture? These things often come down to
signal-to-noise ratio. What kind of noise will there be in the
environment? However you cut it, a microphone will take some kind of
amplifier in order to input a signal to the stamp.
- Tracy
Tracy's suggestion is to attach a bead thermistor temperature sensor
near the nose and mouth. It should act as a flowmeter, with output
varying with air flow -- sort of a micro version of a wind chill factor.
A calibration table of termperature vs flow could be stored in the stamp
as a look up table.
Dennis
Original Message
From: Tracy Allen [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=ihtBKxhFfRYdwAa8dVIAY0DN3SWWFAbPra3se2Qdei_HN5OtP9qI4q362d1uqHOJcMWJ259xrsmo8NcQng]tracy@e...[/url
Sent: Monday, April 08, 2002 9:49 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Re: microphone input to stamp
>well... yeah, i really want to 'dim' the LED (am i being hopelessly
>naive here?:-)
>
>what i was thinking of trying is to control the brightness of an LED
>based on the breathing patterns of an individual. there is more to the
>idea, but that's the basics of what i need to get done.
>
>thanks!
>-k
Would there be other options for sensing, say, the heat of the
breath, or motion or distortion of the chest? Where where you going
to put the microphone? Was it to be attached to the chest, or by the
mouth, or in some kind of fixture? These things often come down to
signal-to-noise ratio. What kind of noise will there be in the
environment? However you cut it, a microphone will take some kind of
amplifier in order to input a signal to the stamp.
- Tracy
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
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Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
This seems like a good idea on the surface, but in practice, the
thermistors need to be very fast and you have to be able to "recover" the
ambient temperature to keep them calibrated to your original calibration
data. In measuring air inspiration in animals (for example, the air gulp
that a singing bird takes before and during singing), the problem is often
the amount of condensation on the bead. People DO get it to work, but it
ain't easy.
If respiration RATE is the only concern, I have had great luck using piezo
transducers from Digikey and velcro around the chest or the neck. The
output of the piezo element needs to be amplified by an opamp but it is a
very easy signal to deal with.
Mike
At 03:31 PM 4/9/2002 -0700, you wrote:
>I've never tried this, but another possibility along the lines of
>Tracy's suggestion is to attach a bead thermistor temperature sensor
>near the nose and mouth. It should act as a flowmeter, with output
>varying with air flow -- sort of a micro version of a wind chill factor.
>A calibration table of termperature vs flow could be stored in the stamp
>as a look up table.
>
>Dennis
>
>
Original Message
>From: Tracy Allen [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=azZC2pgWYKrm84AsO9HDu1c9mzu5LSyha2ycf_c1KLagJGy1WdqmFSSOY4sIR1ZUbQY4sZKtHcaLJlakhqo]tracy@e...[/url
>Sent: Monday, April 08, 2002 9:49 PM
>To: basicstamps@yahoogroups.com
>Subject: [noparse][[/noparse]basicstamps] Re: microphone input to stamp
>
>
> >well... yeah, i really want to 'dim' the LED (am i being hopelessly
> >naive here?:-)
> >
> >what i was thinking of trying is to control the brightness of an LED
> >based on the breathing patterns of an individual. there is more to the
> >idea, but that's the basics of what i need to get done.
> >
> >thanks!
> >-k
>
>Would there be other options for sensing, say, the heat of the
>breath, or motion or distortion of the chest? Where where you going
>to put the microphone? Was it to be attached to the chest, or by the
>mouth, or in some kind of fixture? These things often come down to
>signal-to-noise ratio. What kind of noise will there be in the
>environment? However you cut it, a microphone will take some kind of
>amplifier in order to input a signal to the stamp.
>
> - Tracy
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject
>and Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to
>http://docs.yahoo.com/info/terms/
>
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
>Body of the message will be ignored.
>
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_________________________________
Mike Walsh
walsh@i...
[noparse][[/noparse]Non-text portions of this message have been removed]
>thermistors need to be very fast and you have to be able to "recover" the
>ambient temperature to keep them calibrated to your original calibration
>data. In measuring air inspiration in animals (for example, the air gulp
>that a singing bird takes before and during singing), the problem is often
>the amount of condensation on the bead. People DO get it to work, but it
>ain't easy.
One of my mentors in grad school was studying the respiration of
bumblebees. He had multiple (at least 5) thermocouples implanted in
the abdomen and thorax. (Bees generate heat in their flight muscles
even when they are not flying, and use it to warm up before flight,
or to transfer it to their abdomen to incubate egg clusters. The
heat "valve" is controlled by a sphincter muscle between the thorax
and abdomen. If there is too much heat from flight, they can
transfer it to the abdomen for dissipation.)
Tiny thermocouples, 1 mil in diameter, are extraordinarily fast in
response. True, if condensation forms and then evaporates there is a
strong wet bulb effect. Thermistors can be made extraordinarily
small too. I don't know which would take the prize for "smallest".
Hot wire anemometers are very good for dry clean air, but agreed,
they would be hard to calibrate accurately for respiration of air.
I'm curious, how much air and how often does a bird gulp?
-- Tracy
We have used those thermocouples. They are made by Omega and are really
nice but very fragile. Omega shows the thermocouple next to a bee in their
literature!
The bird song work was done several years ago with zebra finches. I'll
check to see if I can find the numbers. As I remember it, the bird "gulps"
the air during song , rather than normal periodic respiration. I'd like to
have used a Stamp to do the time stamping of those kind of data. The Z-80
slave downloading to a PDP-11 probably didn't perform as well as BS2p would.
Mike
At 05:17 PM 4/9/2002 -0700, you wrote:
One of my mentors in grad school was studying the respiration of
>bumblebees. He had multiple (at least 5) thermocouples implanted in
>the abdomen and thorax. (Bees generate heat in their flight muscles
>even when they are not flying, and use it to warm up before flight,
>or to transfer it to their abdomen to incubate egg clusters. The
>heat "valve" is controlled by a sphincter muscle between the thorax
>and abdomen. If there is too much heat from flight, they can
>transfer it to the abdomen for dissipation.)
>
>Tiny thermocouples, 1 mil in diameter, are extraordinarily fast in
>response. True, if condensation forms and then evaporates there is a
>strong wet bulb effect. Thermistors can be made extraordinarily
>small too. I don't know which would take the prize for "smallest".
>
>Hot wire anemometers are very good for dry clean air, but agreed,
>they would be hard to calibrate accurately for respiration of air.
>
>I'm curious, how much air and how often does a bird gulp?
>
> -- Tracy
>
>
>
>To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
>from the same email address that you subscribed. Text in the Subject and
>Body of the message will be ignored.
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
_________________________________
Mike Walsh
walsh@i...
[noparse][[/noparse]Non-text portions of this message have been removed]