I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

I have this little blue box that works pretty good on my two dogs when they
raise Cain from a visitor or a knock on the door. But its range is not that
good. It runs on a 9v. battery, and is a Big Lots item.

I would like to build one that is very strong, both for gaining some range,
and gaining the dog's attention.

Researching this, I find the 20,000 - 60,000 hz. range to be within their
hearing. Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?

I see several on the market, but they are lax to state just how strong they
are, or their range, mostly seeming to be aimed at home training at short
distances.

TIA

Steve

"Steve B" fired this volley in news:togf18-
:

Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?


Steve, usually one doesn't use a separate tone generator, amplifier, and
speaker for such purposes -- one uses a self-resonant ultrasonic
transducer for the purpose.

It has the benefit of simplicity -- just feed power and it sings. It has
the deficit of not being able to be tuned to other frequencies -- it's
locked to the one resonant frequency the manufacturer assigned. (that's
usually in the 40KHz range). You can also buy "bare" transducer
elements, but you'll have to build up a power oscillator around them,
which is more work than it's worth, considering the cost of the self-
resonant varieties.

Such transducers may be had on the surplus market with outputs so small
they'll barely be heard by a dog at arm's range, and powers so large
they'll burn up unless mounted in a massive heat sink (or under water).

The bigger ones are used for ultrasonic cleaners and sonar applications.

LLoyd

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message
. 3.70...
"Steve B" fired this volley in news:togf18-
:

Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?


Steve, usually one doesn't use a separate tone generator, amplifier, and
speaker for such purposes -- one uses a self-resonant ultrasonic
transducer for the purpose.

It has the benefit of simplicity -- just feed power and it sings. It has
the deficit of not being able to be tuned to other frequencies -- it's
locked to the one resonant frequency the manufacturer assigned. (that's
usually in the 40KHz range). You can also buy "bare" transducer
elements, but you'll have to build up a power oscillator around them,
which is more work than it's worth, considering the cost of the self-
resonant varieties.

Such transducers may be had on the surplus market with outputs so small
they'll barely be heard by a dog at arm's range, and powers so large
they'll burn up unless mounted in a massive heat sink (or under water).

The bigger ones are used for ultrasonic cleaners and sonar applications.

LLoyd

Thank you for the simple explanation. I have seen many hand held devices,
and they range from $10 to $40. They all seem to be rather wimpy in their
performance. The one I have stops some dogs, yet does not faze others. I
wanted to build a strong one, but don't want to have to carry it around on a
two wheel moving dolly. Will investigate the transducer, and if I can find
one cheap, may do an Iggy experiment on it. I have a 9.6 Makita battery
that should do the power.

Steve

Steve B wrote in
rec.crafts.metalworking on Sat, 29 Jan 2011 23:32:21 -0800:

I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

In that case it's not a newsgroup. Perhaps you mean an online forum.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

Why not just use the pepper spray? Bad dog owners/customers get
****ed off?

I have this little blue box that works pretty good on my two dogs when they
raise Cain from a visitor or a knock on the door. But its range is not that
good. It runs on a 9v. battery, and is a Big Lots item.

I would like to build one that is very strong, both for gaining some range,
and gaining the dog's attention.

The only reason they use ultrasonic sound is that people can't hear
it. It doesn't affect the dog any different than any other noise.
Could you use one of those canned air, air-horns?

Researching this, I find the 20,000 - 60,000 hz. range to be within their
hearing. Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?

Long ago, I saw plans for something like that in 'Popular Electronics'
magazine.


--

Dan H.
northshore MA.

On Sat, 29 Jan 2011 23:32:21 -0800, "Steve B"
wrote:

I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

I have this little blue box that works pretty good on my two dogs when they
raise Cain from a visitor or a knock on the door. But its range is not that
good. It runs on a 9v. battery, and is a Big Lots item.

I would like to build one that is very strong, both for gaining some range,
and gaining the dog's attention.

Researching this, I find the 20,000 - 60,000 hz. range to be within their
hearing. Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?

I see several on the market, but they are lax to state just how strong they
are, or their range, mostly seeming to be aimed at home training at short
distances.

TIA

Steve

It's best to keep the freq just above human audibiilty, so somewhere
between 22 KHz and 30 KHz.

The self-resonant piezo transducers generally cannot deliver much
power, except for those used in humidifiers and cleaners, but they
couple to water rather than air.

The good old 555 timer makes a fine tone generator for considerably
less than a buck.
http://www.national.com/ds/LM/LMC555.pdf

You would then need an amplifier to get this up to about 24 volts
peak to zero. A couple of transistors can do this. You'll also need
two 9-volt or 12-volt batteries.

This tweeter can deliver a sound pressure level of 94 dB at 25 KHz for
$1.80:
http://www.parts-express.com/pe/show...number=270-011


An alternative: make a Hartmann whistle that runs off a can of freon.
That might take some experimenting, and the sound pressure levels they
can generate could be dangerous.

On 1/30/2011 5:52 AM, Lloyd E. Sponenburgh wrote:
"Steve fired this volley in news:togf18-
:

Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?


Steve, usually one doesn't use a separate tone generator, amplifier, and
speaker for such purposes -- one uses a self-resonant ultrasonic
transducer for the purpose.

It has the benefit of simplicity -- just feed power and it sings. It has
the deficit of not being able to be tuned to other frequencies -- it's
locked to the one resonant frequency the manufacturer assigned. (that's
usually in the 40KHz range). You can also buy "bare" transducer
elements, but you'll have to build up a power oscillator around them,
which is more work than it's worth, considering the cost of the self-
resonant varieties.

Such transducers may be had on the surplus market with outputs so small
they'll barely be heard by a dog at arm's range, and powers so large
they'll burn up unless mounted in a massive heat sink (or under water).

The bigger ones are used for ultrasonic cleaners and sonar applications.

LLoyd


without the original context, this answer may not make sense, but for a
"simple tone generator", nothing is simpler than a 555 chip. look it up
on the web, see the national semi application handbook - it is one of
the easiest to use chips I've come across and it is really really useful.

--
www.wbnoble.com

On 01/30/2011 10:26 AM, Don Foreman wrote:
On Sat, 29 Jan 2011 23:32:21 -0800, "Steve B"
wrote:

I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

I have this little blue box that works pretty good on my two dogs when they
raise Cain from a visitor or a knock on the door. But its range is not that
good. It runs on a 9v. battery, and is a Big Lots item.

I would like to build one that is very strong, both for gaining some range,
and gaining the dog's attention.

Researching this, I find the 20,000 - 60,000 hz. range to be within their
hearing. Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?

I see several on the market, but they are lax to state just how strong they
are, or their range, mostly seeming to be aimed at home training at short
distances.

TIA

Steve

It's best to keep the freq just above human audibiilty, so somewhere
between 22 KHz and 30 KHz.

The self-resonant piezo transducers generally cannot deliver much
power, except for those used in humidifiers and cleaners, but they
couple to water rather than air.

The good old 555 timer makes a fine tone generator for considerably
less than a buck.
http://www.national.com/ds/LM/LMC555.pdf

You would then need an amplifier to get this up to about 24 volts
peak to zero. A couple of transistors can do this. You'll also need
two 9-volt or 12-volt batteries.

This tweeter can deliver a sound pressure level of 94 dB at 25 KHz for
$1.80:
http://www.parts-express.com/pe/show...number=270-011


An alternative: make a Hartmann whistle that runs off a can of freon.
That might take some experimenting, and the sound pressure levels they
can generate could be dangerous.

Most of us on the group can't hear 25kHz any more, but when my sisters
and I were kids (my sisters up to their late 20s) you'd have us
experiencing pain with a loud noise at that frequency.

If you want to get it above the range of the hearing of all humans, not
just geezers, make it 30kHz.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html

In article ,
Tim Wescott wrote:

On 01/30/2011 10:26 AM, Don Foreman wrote:
On Sat, 29 Jan 2011 23:32:21 -0800, "Steve B"
wrote:

I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

I have this little blue box that works pretty good on my two dogs when
they
raise Cain from a visitor or a knock on the door. But its range is not
that
good. It runs on a 9v. battery, and is a Big Lots item.

I would like to build one that is very strong, both for gaining some
range,
and gaining the dog's attention.

Researching this, I find the 20,000 - 60,000 hz. range to be within their
hearing. Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?

I see several on the market, but they are lax to state just how strong
they
are, or their range, mostly seeming to be aimed at home training at short
distances.

TIA

Steve

It's best to keep the freq just above human audibiilty, so somewhere
between 22 KHz and 30 KHz.

The self-resonant piezo transducers generally cannot deliver much
power, except for those used in humidifiers and cleaners, but they
couple to water rather than air.

The good old 555 timer makes a fine tone generator for considerably
less than a buck.
http://www.national.com/ds/LM/LMC555.pdf

You would then need an amplifier to get this up to about 24 volts
peak to zero. A couple of transistors can do this. You'll also need
two 9-volt or 12-volt batteries.

This tweeter can deliver a sound pressure level of 94 dB at 25 KHz for
$1.80:
http://www.parts-express.com/pe/show...number=270-011


An alternative: make a Hartmann whistle that runs off a can of freon.
That might take some experimenting, and the sound pressure levels they
can generate could be dangerous.

Most of us on the group can't hear 25kHz any more, but when my sisters
and I were kids (my sisters up to their late 20s) you'd have us
experiencing pain with a loud noise at that frequency.

If you want to get it above the range of the hearing of all humans, not
just geezers, make it 30kHz.

Agree. When I was in my 20s, I could sense 26 KHz, as in ultrasonic
burglar alarms used in stores. So could my then ~GF.

Joe Gwinn

On 2011-01-30, Steve B wrote:

Thank you for the simple explanation. I have seen many hand held devices,
and they range from $10 to $40. They all seem to be rather wimpy in their
performance. The one I have stops some dogs, yet does not faze others. I
wanted to build a strong one, but don't want to have to carry it around on a
two wheel moving dolly. Will investigate the transducer, and if I can find
one cheap, may do an Iggy experiment on it. I have a 9.6 Makita battery
that should do the power.


Steve, an easy route to take would be to make an ultrasound whistle
that is compressed air powered or even the kind that you blow air
into. Most whistles are, of course, made to be heard by regular
people, and those can be VERY loud and unpleasant to hear. All you
need to do it build/make one that makes ultrasound. That is determined
by certain chamber dimensions. Based on nothing but gut feel, I would
expect that a whistle with two times smaller chamber should make two
times higher sound frequency.

i

On 2011-01-30, Don Foreman wrote:
On Sat, 29 Jan 2011 23:32:21 -0800, "Steve B"
wrote:

I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

I have this little blue box that works pretty good on my two dogs when they
raise Cain from a visitor or a knock on the door. But its range is not that
good. It runs on a 9v. battery, and is a Big Lots item.

I would like to build one that is very strong, both for gaining some range,
and gaining the dog's attention.

Researching this, I find the 20,000 - 60,000 hz. range to be within their
hearing. Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?

I see several on the market, but they are lax to state just how strong they
are, or their range, mostly seeming to be aimed at home training at short
distances.

TIA

Steve

It's best to keep the freq just above human audibiilty, so somewhere
between 22 KHz and 30 KHz.

The self-resonant piezo transducers generally cannot deliver much
power, except for those used in humidifiers and cleaners, but they
couple to water rather than air.

The good old 555 timer makes a fine tone generator for considerably
less than a buck.
http://www.national.com/ds/LM/LMC555.pdf

You would then need an amplifier to get this up to about 24 volts
peak to zero. A couple of transistors can do this. You'll also need
two 9-volt or 12-volt batteries.

This tweeter can deliver a sound pressure level of 94 dB at 25 KHz for
$1.80:
http://www.parts-express.com/pe/show...number=270-011


An alternative: make a Hartmann whistle that runs off a can of freon.
That might take some experimenting, and the sound pressure levels they
can generate could be dangerous.


Don, I recall reading somewhere that high levels of ultrasound may not
be heard, but they can still damage hearing further.

i

"dan" wrote

Why not just use the pepper spray? Bad dog owners/customers get
****ed off?

At times, the dogs are tied out front, or are in the back yard, and just
bark, bark, bark, bark, bark ................. I cannot pepper spray them
unless they are very close to biting me, or then I have a ****ed off owner
on my hands. I just want something to make them STFU for five minutes until
I'm gone.

The only reason they use ultrasonic sound is that people can't hear
it. It doesn't affect the dog any different than any other noise.
Could you use one of those canned air, air-horns?

Again, that might scare the heartbeat out of some old fart in the area. And
draw immediate attention to me.

Steve

Joseph Gwinn wrote:

In article ,
Tim Wescott wrote:

On 01/30/2011 10:26 AM, Don Foreman wrote:
On Sat, 29 Jan 2011 23:32:21 -0800, "Steve B"
wrote:

I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

I have this little blue box that works pretty good on my two dogs when
they
raise Cain from a visitor or a knock on the door. But its range is not
that
good. It runs on a 9v. battery, and is a Big Lots item.

I would like to build one that is very strong, both for gaining some
range,
and gaining the dog's attention.

Researching this, I find the 20,000 - 60,000 hz. range to be within their
hearing. Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?

I see several on the market, but they are lax to state just how strong
they
are, or their range, mostly seeming to be aimed at home training at short
distances.

TIA

Steve

It's best to keep the freq just above human audibiilty, so somewhere
between 22 KHz and 30 KHz.

The self-resonant piezo transducers generally cannot deliver much
power, except for those used in humidifiers and cleaners, but they
couple to water rather than air.

The good old 555 timer makes a fine tone generator for considerably
less than a buck.
http://www.national.com/ds/LM/LMC555.pdf

You would then need an amplifier to get this up to about 24 volts
peak to zero. A couple of transistors can do this. You'll also need
two 9-volt or 12-volt batteries.

This tweeter can deliver a sound pressure level of 94 dB at 25 KHz for
$1.80:
http://www.parts-express.com/pe/show...number=270-011


An alternative: make a Hartmann whistle that runs off a can of freon.
That might take some experimenting, and the sound pressure levels they
can generate could be dangerous.

Most of us on the group can't hear 25kHz any more, but when my sisters
and I were kids (my sisters up to their late 20s) you'd have us
experiencing pain with a loud noise at that frequency.

If you want to get it above the range of the hearing of all humans, not
just geezers, make it 30kHz.

Agree. When I was in my 20s, I could sense 26 KHz, as in ultrasonic
burglar alarms used in stores. So could my then ~GF.


I've had to scrap two working SVGA monitors because their H sweep was
giving me headaces.


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

Steve B wrote:
I subscribed to some electronics newsgroups, but as of yet haven't
passed through their process to get messages.

I want to build an ultrasonic dog repeller. I do real estate
inspection, and there are times that I encounter either obnoxious
dogs or aggressive dogs. I carry pepper spray, and have almost had
to use it, pitbulls both times.

I have this little blue box that works pretty good on my two dogs
when they raise Cain from a visitor or a knock on the door. But its
range is not that good. It runs on a 9v. battery, and is a Big Lots
item.
I would like to build one that is very strong, both for gaining some
range, and gaining the dog's attention.

Researching this, I find the 20,000 - 60,000 hz. range to be within
their hearing. Is there anywhere I can buy a simple tone generator,
or kit that will let me build one of these. Is tone generator what I
need to be searching for, or is there another term?

I see several on the market, but they are lax to state just how
strong they are, or their range, mostly seeming to be aimed at home
training at short distances.

Once you have this, don't get complacent. Someday you'll run into a deaf dog.

On Sun, 30 Jan 2011 16:34:01 -0600, Ignoramus17662
wrote:



This tweeter can deliver a sound pressure level of 94 dB at 25 KHz for
$1.80:
http://www.parts-express.com/pe/show...number=270-011


An alternative: make a Hartmann whistle that runs off a can of freon.
That might take some experimenting, and the sound pressure levels they
can generate could be dangerous.


Don, I recall reading somewhere that high levels of ultrasound may not
be heard, but they can still damage hearing further.

i

I researched this some years ago. What you say is true if the
ultrasound levels are well over 130 dB, intense enough to kill mice in
a bell jar. No risk with a piezo tweeter, might want to be a bit
careful with a Hartmann whistle.

On Sun, 30 Jan 2011 14:59:35 -0800, "Steve B"
wrote:


"dan" wrote

Why not just use the pepper spray? Bad dog owners/customers get
****ed off?

At times, the dogs are tied out front, or are in the back yard, and just
bark, bark, bark, bark, bark ................. I cannot pepper spray them
unless they are very close to biting me, or then I have a ****ed off owner
on my hands. I just want something to make them STFU for five minutes until
I'm gone.

The only reason they use ultrasonic sound is that people can't hear
it. It doesn't affect the dog any different than any other noise.
Could you use one of those canned air, air-horns?

Again, that might scare the heartbeat out of some old fart in the area. And
draw immediate attention to me.

Steve


Earplugs.

Newb

Look up Sylvania 555.

Its an oscilating IC. You can do all kinds of things with a couple of them.
Add a small amplifier and a speaker that can reproduce the sound you are
looking for. You used to be able to buy a cheap amplifier kit at Radio
Shack, but they may no longer be available.

Bob La Londe wrote:

Look up Sylvania 555.

Sylvania? National Semiconductor and Signetiics were the two big
manufacturers. Sylvania had the ECG line, but sold it to Philips long
before Philips sold it to NTE.


Its an oscilating IC.


It's a timer than can be used in a monostable mode or an astable free
running mode.


http://www.national.com/mpf/LM/LM555.html#Overview
http://www.national.com/profile/snip.cgi/openDS=LM555


You can do all kinds of things with a couple of them.
Add a small amplifier and a speaker that can reproduce the sound you are
looking for. You used to be able to buy a cheap amplifier kit at Radio
Shack, but they may no longer be available.


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

One thing that people forget is Foret an his equations...

Harmonics and sums and subtractions...

A super sonic can be heard if it 'beats' with another supersonic
frequency. The difference frequency might be heard and hammers you.

I don't care for the old concept cell / telephone system we have -
chops the low and high - sends middle frequency - So some of us
that have loss in some frequencies have no access to the harmonics.

Martin

On 1/31/2011 10:58 AM, Don Foreman wrote:
On Sun, 30 Jan 2011 16:34:01 -0600, Ignoramus17662
wrote:



This tweeter can deliver a sound pressure level of 94 dB at 25 KHz for
$1.80:
http://www.parts-express.com/pe/show...number=270-011


An alternative: make a Hartmann whistle that runs off a can of freon.
That might take some experimenting, and the sound pressure levels they
can generate could be dangerous.


Don, I recall reading somewhere that high levels of ultrasound may not
be heard, but they can still damage hearing further.

i

I researched this some years ago. What you say is true if the
ultrasound levels are well over 130 dB, intense enough to kill mice in
a bell jar. No risk with a piezo tweeter, might want to be a bit
careful with a Hartmann whistle.

On Mon, 31 Jan 2011 20:55:32 -0600, Martin Eastburn
wrote:

One thing that people forget is Foret an his equations...

I'll bet you mean Fourier.

Steve B wrote:
I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

(...)

What about this, Steve?

http://www.harborfreight.com/transon...ler-96743.html

--Winston