The discussed circuit is designed to discourage dogs from barking in the selected zone by the generation of a synchronized ultrasonic sound waves in response to a few initial barking of a particular dog.
The circuit when correctly optimized will produce a high pitched ultra sonic sound each time it senses a dog bark. Since the sound is in the ultrasonic range will be inaudible to humans, and audible to only dogs present in the vicinity.
Contents
How the Dog Bark Terminator Works
Note: Please use 1uF capacitor for C2 to ensure a foolproof triggering of the IC1 stage...
Parts List
- Resistors all 1/4 watt 5%
- R1, R3 = 10K
- R2, R4, R5, R7 = 100K
- R6 = 33K
- R7 = 1K
- Capacitors
- C1 = 0.1uF, disc ceramic
- C2 = 1uF/25V
- C3 = 10uF/25v
- C4, C6 = 0.01uF ceramic
- C5 = 680pF ceramic
- Transistors
- Q1 = 2N3904 or BC547
- Q2 = TIP122
Referring to the above shown dog bark inhibitor circuit, we can see three distinct stages involved, the sound sensor and preamplifier circuit using the Q1 and the electret MIC stage, the monostable stage using IC1 and the associated parts and the ultrasonic sound generator stage using the IC2 and the speaker driver stage.
Whenever a dog barks, the Mic detects it causing a sequential low and high pulse at the base of T1. T1 responds to this and produces an equivalent amplified signal across C2, which in turn triggers the pin#2 of the monostable IC1.
The above action forces IC1 to produce a high at its pin#3 for a period determined by the values of R5/C3.
This high at pin#3 of IC1 enables the reset pin#4 of IC2 to become active thereby allowing the astable IC2 to supply the ultrasonic pulse at its pin#3, which is appropriately amplified by the associated TIP122 transistor, driving the connected speaker.
The speaker vibrates at the specified amplified level throwing the ultrasonic sound in the direction where the dogs need to be driven away.
The above sound waves is supposed to fluster the dogs and cause a lot of disturbance in their ears due to its high pitched sound, and also due to its synchronized effect with the dog's own barking sequence.
Actually the above dog barking stopping device might respond to all types of high dB sound levels, however since it won't be audible to a human ear this will never be an issue, and may be ignored.
Making the Circuit more Sensitive
If you find the above dog barking prohibitor circuit not responding to barking signals or any sound distant signals correctly, then you must try upgrading the MIC stage with an IC based MIC amplifier stage as shown in the following image:
Once you build the above circuit, you can eliminate or remove R1, R2, C1 from the first circuit, and replace it with the mentioned op amp based MIC amplifier circuit and configure the C3 output from the op amp with the base of Q1.
This upgrade will ensure that the circuit responds appropriately even to weak sound signals, specifically dog barking sound during night time, and trigger the IC 555 stages for the intended results.
Increasing the Range over 50 Meters
To make the above design respond to dog barks at distances over 50 meters, the following modified idea could be tried.
However this circuit being extremely sensitive could get triggered by other forms of sounds in the vicinity.
PCB Design
UPDATE: A Much Simplified Design
A simple transistorized circuit presented below can be used as effectively as the above designs for repelling dogs or any other animal away, from a distance.
The parts list for the above design is shown below:
- R1 = 5k6
- R2 = 47k
- R3 = 3M3
- R4 = 33K
- R5 = 330 OHMS
- R6 = 2K2
- C1 = 0.1uF
- C2 = 1uF/25V
- T1, T2 = BC547
- T3 = TIP127
- D1 = 1N4007
- Mic = electret condenser MIC.
If you wish to use some other form of deterrent instead of the indicated high power alarm, you can replace the speaker with a relay and connect the desired load with the relay contacts. The relay based design is demonstrated in the following diagram:
The parts list will be the same as above, except the T3, which can be replaced with BC557 transistor.
How it Works
As soon as a relatively loud noise such as a dog barking sound is detected by the MIC, the signals are amplified by the subsequent BJT stages, which activates the relay momentarily. This momentary delay of the relay activation is determined by the value of C2, which can be adjusted to best suit the application.
The relay contacts can be hooked up with a suitable high frequency circuit, such as an electronic dog whistle.
Improving Further
In the above design, the relay can be eliminated, and the T3 collector output can be directly used to activate the IC 555 frequency generator circuit, as shown in the following figure:
Anton says
Dear Sir,
Is it possible to use a Piezo Speaker instead the 8Ohm Speaker.
Kind regards
Anton
Swagatam says
Hi Anton,
Yes a piezo speaker can be used instead of an ordinary speaker.
Paolo says
Hi,
I realized the circuit in Eagle and made a PCB, but something is strange happened, when I connect the speaker, it put out high frequency and a random bump sound without any sounds reached from the mic…
Here the circuit:
I checked all components and circuit, I miss something or something is wrong?
Thanks for any help! Much appreciated!
Cheers from Italy
Swagatam says
Hi,
Please do the following checks.
Disconnect the C2 connection from the IC1 and check the audio, the audio should stop. Once this is confirmed, manually touch pin#2 to ground momentarily. This should enable the high frequency sound output for some moments, and then stop again.
The above will confirm that the IC 555 is correctly configured and is working correctly.
Let me know the above results first.
Paolo says
Done all things you said and all is correct
Swagatam says
So the problem could be with the MIC circuit. If you want perfect results from the MIC circuit then you can build the following circuit and connect the relay contacts with IC 555 stage.
Can you build the following circuit and test it separately? This design is a tested design:
https://www.homemade-circuits.com/wp-content/uploads/2015/08/sound2Bactivated2Brelay2Bcircuit.png.webp
However, the best and easiest option is the last circuit which should work without fail. You can try that also.
https://www.homemade-circuits.com/wp-content/uploads/2022/04/dog-barking-preventer.jpg
Paolo says
Hi, I’m going with the second circuit that you advised me. A question, the output pin3 of the ne555 is enought powerfull, or can I use a 1k resistor and transistor tip 122 for a more powerfull output like first schematics?
Thanks
Swagatam says
Sure, you can try it.
The pin#3 directly will not produce enough power, so you can use a TIP122 to boost the output.
Please connect an LED with series 1K resistor between the collector of 2N2907 and the ground line for instant indication of the MIC activation.
Paolo says
Great! last question :D, I realized it and working good, but now the mic is super sensitive, I need that the only loud sounds can activate it, any way to have a less sensisive mic?
Thanks a lot for your help!
Swagatam says
Glad to know it is working now. You can probably try increasing the value of R1 to make the MIC less sensitive,
Paolo says
Hi! Thanks a lot for share the schematics, there is maybe a Eagle project for create a pcb of the first schematic?
Greeting from Italy
Paolo
Swagatam says
Hi, Sorry, presently we don’t have an Eagle PCB project for this schematic.
vijaykumar D. Baravkar says
I saw your dog barking terminator circuit, very good, but i want to buy it. shall i get it ? i prepaid the all amount with courier charges. Pl. inform me.
Swagatam says
I understand that you are looking for a ready made barking terminator circuit, However I am really sorry, due to lack of time it will be difficult for me to build a prototype for you.
Vijay Kumar Baravkar says
O.k sirji.It’s all right. Thanks for reply
roberto says
good morning,
very interesting circuits,
after the microphone you could put one or more band pass filters with a frequency equivalent to the barking dog?
What is the difference between your circuit with two 555s and the last one with three BJTs?
Thanks and congratulations
Swagatam says
That sounds a great idea, but the bandpass frequency will need to be calculated precisely, which can be a little problem.
The last circuit is easier to build, more accurate and more efficient than the circuits provided at the top.
roberto says
dear Swagatam,
with spectrum analyzer I noticed the frequencies of the barking dog:
they are 562Hz and 662Hz.
After the amplification of the microphone you could insert filters like those of the graphic equalizer, so the ultrasonic intervention is precise.
If you want, I would like to collaborate financially in your on-line commitment
Roberto
Swagatam says
Thank you Dear Roberto,
I understand your idea and appreciate it very much.
However, adding a filter circuit could make the design quite complex and the ordinary people may find it difficult to build and set it up.
Surely an electronic experts will find your idea useful and might go for it.
I am not involved with any financial gains using this circuit…if you want to use it for some commercial purpose, you can definitely go ahead with it, no problems at all.
roberto says
good morning Swagatam,
thank you for your consideration,
a Notch filter has 3 resistors and 3 capacitors and would prevent any noise from activating the ultrasounds;
my use is private only, not commercial;
hello and good luck
Swagatam says
Thank you Roberto,
Noted!
I agree with you.
I hope somebody designs this notch filter and provides the schematic here for updating.
Pradeep says
For customized requirements, instead of MIC in the repellant circuit , i want use push button… Please suggest
Swagatam says
For a push button operation you can simply use the following design. You should adjust the 4K7 resistors so that the speaker generates a sharp “hissing” noise.
Dewald Naude' says
Hi Swagatam
I build this dog barking unit of yours, its working well, thanks, I did not measure the KHz yet, that it is supposed to kick out. I believe from other posts it’s 13 KHz. Is it possible to adjust your original circuit design to increased the 13 KHz from your original KHz to an adjustable 100KHz frequency? In other words, I want to play with the frequency from i.e. 13KHz to 100KHz.
If this is the case, can you please tell me what components to change with what?
Or is this now a totally different ball game? With an new circuit design?
Must say this is very interesting.
Thanks for the support and time.
Regards
Dewald Naude’.
Swagatam says
That’s awesome Dewald, thank you for building this circuit successfully. Yes you can definitely play with the frequency of the IC2 555. You just have to adjust the C5 value (which is 680pF in the present circuit) for getting different frequencies as desired by you. Smaller values will give higher frequencies and vice versa.
You can also refer to the newly updated circuit at the bottom of the post which is much easier to build and adjust.
Allen Hewitt says
Thank you for your reply. This is all foreign to me. Please forgive my ignorance. I was referring to the simplified design which does not have a C3 or a 1C1 unless I am overlooking them. Also, I see the + 5 V lead wire in the top right corner. I assume the – 5V is one of the 2 open leads in the bottom right. Either the O line or the black box. I’m not sure which, my inclination in the O. Please clarify and could you explain what the remaining line is? Thank you!!!!
Swagatam says
I guess you are referring to the last two circuits. Yes the bottom black line is the ground line or the supply negative line. You can connect the negative anywhere on that line.
Allen Hewitt says
Instead of using a microphone to activate the ultrasonic sound, can you use a switch or button? Also, can you limit the time the ultrasonic sound is emitted?
Swagatam says
yes a switch can be replaced for the MIC. C3, R5 associated with IC1 can be altered as desired to limit the sound output duration
Peter says
Hi Swagatam,
thanks for your quick informative reply…I will give this a try tonight
appreciate your help
regards Peter
Swagatam says
You are welcome Peter!
Peter says
Hi Swagatam,
I just need to clarify what type of capacitor c2 is ? and if it is electrolytic where does the positive terminal go ?thanks Peter
Swagatam says
Hi Peter, the C2 capacitor which is connected at pin#2 of IC1 can be any ceramic disc capacitor. For better response you can replace it with a 1uF/25V electrolytic capacitor. The positive lead will go to pin#2 of IC1
Peter says
Hi Swagatam,
Thanks for your reply have have stage IC1 working well.
I need to ask for your help on this IC2 stage and am trying to measure a stable frequency on my Rigol 1054z oscilloscope.
I have removed the link wire from pin#3 from IC1 and pin#4 on IC2 stage and have connected pin#4 on IC2 to 12v + to get a continuous signal from IC2
Now I connect My probes ground to – and + to pin#3 before the resistor
I can not get a stable wave form or frequency , I used the counter Function in scope but seem to get variable MHz frequencies
I have changed out to new 555 IC … Same signal.
Is there away so I can hear a tone come out of speaker then I know there something to measure and then I can trouble shoot this ?
Questions:
1) what wave form should I see?
2) does pin #6 need to be connect to pin# 2 on IC2 ?
3) can you suggest the settings for my scope to measure this correctly so I can see the approx 13hz as you know this circuit and probably have more skills on oscilloscope than me.
Appreciate all you help
And yes the dog is still barking 🙁
Best regards Peter
Swagatam says
Hi Peter,
The waveform from the output of the IC2 555 circuit will be an ordinary rectangle wave, and it should be in kHz, not in MHz. You can try increasing the value of C5 to 1uF and check whether the frequency comes down to lower levels or not.
You can check out the waveform of a similar circuit in the video presented in the following article
https://www.homemade-circuits.com/how-to-use-ic-555-for-generating-pwm/
Yes pin#2 and pin#6 are connected with each other.
The adjustments of the scope will be normal as done for measuring any frequency, just try adjusting the range so that the waveform appear clearly on the display.
A tone can be heard if you use a 1uF capacitor for C5 and then replace R7 with a 100 pot with a 10K series resistor. Once this is done you can adjust the 100k pt to hear a varying tone on the speaker. Don’t forget to put the 10K series resistor.
Peter says
Hi Swagatam,
thank you for informative quick reply
Now just regarding your comment (Yes pin#2 and pin#6 are connected with each other.)
on the drawing IC2 there is no connection to pin#6 marked across to Pin#2
I will try this tonight
thank you again Peter
Swagatam says
You are welcome Peter, in the diagram, the pin#2 and pin#6 are joined together, but the marking are not done correctly. The pin numbers are marked little on the upper side and not exactly beside the pinouts.
Peter says
Hi Swagatam,
Thanks for you quick reply and I now have this working
I found out why my IC2 stage was never working after our last message I realized that I have gone exactly off the main diagram drawing for the pin connections where the lines where drawn.
This what I had interpreted on drawing lines as connections to IC2 and I had wrong.
pin #1 was connected to Ground and Top of C5 (I removed this link to C5) from pin#1
pin#6 I had no connections as per drawing (have added pin#6 and pin#2 Link wire)
I turn it on its now running I can see a proper wave form first time and can change frequency range with my Pot to see variable 13 Khz on oscilloscope
hope this helps someone else if they did what I did.
I am no expert on these circuits but have learnt a lot here about the 555 timer modes and functions thanks for your quick replies Swagatam this was a great help ….. now to get this project into a case and give the dog next door his new present
thank you for all your help
best regards Peter
Swagatam says
That’s great Peter,
Glad this site is helping you to learn more about electronics. Please keep up the good work, and let me know if you have anymore questions.
Peter says
Hi Again Swagatam,
I cant believe my luck …now my sound trigger circuit does not work 🙁
things I have done:
1) added a extra led and 1k on pin 3 (when I power up the IC1 flashes red for a second then off
same as the led on IC2 they both momentarily flash on …(correct)?
2) I have added a 1uf electrolytic for C2… positive towards pin#2 on IC1 to ensure full proof trigger
3) have tested mic stage working placing probe on positive leg C2 and see wave forms of sound on oscilloscope when clapping hands
4) I have triple checked all components and connections
5) swapped out IC1 and Q1 several times
Questions:
1) can I keep Led permanently in circuit this led and 1k resistor in place to keep checking 555 IC1 condition?
2) Is there away for me to troubleshoot this …Multi meter , Oscilloscope measurements on IC1 stage at points what voltages I should see on certain point etc.:?
3) is there away to check the 2n3904 is working correctly ?
4) also I notice 2 different pin outs on the web for this Transistor ? I have Flat surface facing me emitter to left and ground ?
please let me know your thoughts on this?
thank you
regards Peter
Swagatam says
Hi Peter, there’s no issue of luck here 🙂 The circuit is very straightforward and should work without fail, however this circuit can be difficult for a newcomer. The person who is building this circuit must have full knowledge of all the basic aspects of electronics only then he will be able to quickly adjust the various parameters and make the circuit work.
Honestly, it will be difficult for me to troubleshoot your circuit unless I check it myself practically.
Therefore, I would suggest you to build the last transistorized circuit and configure the relay contacts with the IC2 555 oscillator which you have already built.
Since you have already tested the IC2 555 astable, testing and integrating the transistorized circuit will be much easier and you might get 100% results quickly.
Peter says
Hi Swagatam,
Great work….. I now have a German shepherd next door and don’t sleep any more so I will see what parts I have laying around and start building your circuit
Question : is it possible to use a Plastic Horn type (20W 4″ Dual Tone Alarm Siren) as a Speaker for this circuit?
cheers Peter
Swagatam says
Thank you Peter, I think it should work, you can try it.
Peter Brunner says
Hi Swagatam,
thanks for your reply
now I have the circuit built and it seems to be running but need to confirm a couple of things
1) I am no expert but I have an oscilloscope and where exactly to correctly measure the generating frequency?
2) you mentioned to check circuit connect a led in series with TIP122 base ..to clarify what you are saying is this between the 1k resistor and the base of TIP122 with positive of led on Base? I just don’t want to blow any thing up
appreciate your help
thank you Peter
Swagatam says
Thanks Peter,
1) The oscilloscope should be connected across pin3 of IC2 and ground.
2) Yes that’s correct, the LED can be in series with the base resistor of TIP122, either between pin#3 and 1K, or between 1K and the transistor base. Positive or the anode of the LED will go towards pin#3 of IC2, and the negative or the cathode towards the base of the transistor.
Peter says
Hi Swagatam,
Well I installed the led and power on circuit, led lit then went out I clapped my hands led lit monetary and went out but after about a minute of clapping it just stayed on with now tweeter speaker attached.
Now when I attached speaker I clap once and the led stays on
I measured voltage across speaker terminals around 11.5 volts close to 1 amp draw, I disconnected straight away … is this correct ? Let me know your thoughts on this regards Peter
Swagatam says
Hi Peter, the initial response from the circuit was correct. IC1 is supposed to switch ON the IC2 momentarily and then switch OFF after sometime whenever a sound is detected on the MIC.
It seems your IC1 has stopped working or has gone bad. You can try adding another LED with 1K series resistor across pin3 of IC1 and ground….if this LED lights up momentarily and switches off then your IC1 is OK, IC2 may be blown.
You can also try operating the circuits using 5V or 9V and check the response
Dewald Naude' says
Hi Swagatam,
I am interested to try your circuit for 50 meter extended dog barking circuit. Instead of making use of the MIC to trigger it, I want to make use of a spring return push button, so actually I want to manually trigger it when ever the dog is irritating me. Is that possible to modify the 50 meter range circuit to be able to operate with a push button? Can you please send me the modified circuit without a MIC but with a push button to triggers it.
My thinking was to mount the unit on my roof facing my Nabors house, with my trigger push button in my house, so when ever the dog irritates me I want to push the button to trigger it, without going out of my own home. I believe if you keep it on for to long the dog get use to it and basically ignore it later on.
Thanks in advance
Dewald Naude
E-Mail: friend.naude082@gmail.com
Swagatam says
Hi Dewald, the modified design can be seen in the following image. But I doubt whether a manual action will help to repel the dog barking or will it cause the dog to bark even more due to irritation. The dog barking is supposed to stop only when the noise is generated immediately after the dog barks and stops within a few seconds….this type of triggering discourages the dog from barking any further. Anyhow let’s see how it works, make sure to tweak the values of R6, R7, C5 so that it produces just the right kind of noise, which may be loudly audible to the dog but inaudible to humans.
John Willden says
I found your wiring of IC 2 to be ambiguous.
The text for pin 6 and pin 2 should be lower to match the lines.
file:///home/john/Documents/ElectronicProjects/Debarker/correction.png
Swagatam says
Yes you are right, the pin6 and pin2 are not correctly positioned, but I think the readers will understand and correct this small mistake.
Carlos Zamora says
Thank you.
Charlie says
Hi Swagatam,
I am using a ultrasonic generator with a L010 Piezo Loudspeaker. This combination doesn’t seem to do the job. The dogs just keep on barking. I was wondering if your design is more powerful than this combination? Please let me know.
Also, is your design effective even if it is inside a room? I apologize but I am “electronically challenged” so I really need your feedback and help. Thank you so much in advance!
Swagatam says
Hi Charlie, first you have to confirm is your circuit toggling ON in response to the barking of the dogs, or any loud sound? Next, you have to confirm is the frequency generator stage correctly generating the required frequency? The circuit is effective anywhere, inside a room or outside, as long as the above two things are confirmed working. These can be basically confirmed using LED indicators, and also through manual listening.
I would recommend using the last circuit, were the relay toggling will confirm the MIC response of the circuit. The relay contacts can be then configured with an frequency generator circuit which is able to generate a sharp hissing like sound. The speaker can be in fact any ordinary 8 ohm loudspeaker.
Charlie says
Hi Swagatam,
Wow! Thank you for the quick response! Yes, the unit is working because when I turn it on, I can hear a chirp and when I adjust the knob, I can hear a sound and as the frequency gets higher the sound disappears. It is also confirmed by a lit led that is built in the generator.
I will try your recommendation, thank you. Can you recommend some YouTube video tutorial(s) I can watch to learn how to actually build a circuit? Thanks again for your feedback, it is much appreciated.
Swagatam says
Thank you Charlie, glad to know it is working, however, the output noise is supposed to be triggered only in response to an external loud sound, and it must be only momentarily ON, then OFF.
Presently I do not have any related video, if possible I may try to create one in the near future and update it here.
Charlie says
Thank you, Swagatam. That would be helpful. I am getting familiar with what every component does, eg. resistor, capacitor, transistor, etc., then I will start working on the circuit. I will use a breadboard initially to get it up and running. The next step would be have printed circuit board made.
You mentioned any loudspeaker would do, so long as it’s an 8 ohm. What about the wattage of the speaker, does it matter? Also will it only work on DC? Is there a way for it to run on AC? The deeper I get in to this project, the more interesting it gets. Thank you again, Swagatam.
Swagatam says
You are welcome Charlie. Yes, first it needs to be checked over a breadboard or a veroboard before a PCB can be decided.
An 8 Ohm 2 watt speaker should be enough, however, the frequency is crucial and should be manually checked to verify exactly which frequency is most disturbing for the dogs. According to me a high frequency whistling sound should be most effective. You can use a 12V AC to DC adapter for powering the circuit
Charlie says
Thank you for help, Swagatam.
Swagatam says
You are welcome Charlie!
Charlie says
Hi Swagatan,
I tested my ultrasonic generator, it works. It’s specs says that you can hook up, up to 5 piezo speakers to the unit. What is the best way to connect the speakers, parallel or series. I’m going to connect 4 speakers to one generator. Thank you in advance.
Charlie
Swagatam says
Hi Charlie, you can connect the piezo devices in parallel according to my understanding.
dedopata says
I can’t get a lm386a here in argentina, i can get lm386, lm386m, lm386n-1, lm386n-4.
Can i use any of them instead of lm386a?
Swagatam says
yes any of them will do…
Andy says
Hi Swagatam, On the simplified design, what is the “high powered noise alarm” ? What would I buy in the local electronics store? Does it have a particular code or number ? Also, can this circuit be modified to work when you push a button? That way I can carry it around and activate it when a dog scares the crap out of me when i go past a gate. Thanks !
Swagatam says
Hi Andy, the alarm can be any horn that can produce a loud sound or a loud dog barking sound generator circuit, however this may not be a good idea, since although this would deter the dog, it could also cause harassment to the neighbors.
So according to me this alarm should be any high frequency generating circuit, through a tweeter like speaker.
Yes a push button can be used connected in parallel to T3 emitter collector pins.
Mario Buratto says
what are the dimensions of this speaker? Is this a tweeter? Its power is 50w?
Swagatam says
ideally it should be a tweeter, although a normal 8 ohm 50 watt loudspeaker can also be used.
Michael Costello says
Does it work on dogs
How does it compare to devices on sale for this issue
Gilbert says
Tried contacting that shop again, they were even less helpful, so I tried their online shop, ok you have to buy packs of 100 resistors, and the first one I tried to order was out of stock with an unknown replacement date. 🙂
Will try to find someone online to make it and send by post (I’m in Portugal at the moment).
Thanks again
Swagatam says
OK! thanks for updating!
Gilbert says
Update to not much…
Contacted a UK manufacturer, sent your diagram of the circuit. They replied that:
“We would need to review the manufacturing data for your circuit, which would be in GerberX2 / GerberRS274X / ODB++ format.”
Whatever that means. Even if it’s a simple circuit, they can’t work it out from a diagram and your list of every component. Any suggestions? I don’t want to have to buy 1,000 resistors if I only need a handful.
Swagatam says
Sorry, it won’t be possible for me to create the Gerber files. The only option is to buy the spare parts and assemble at home. I am recommending the last two circuits since they are perfectly tested.
Resistor are very cheap so buying a few hundred won’t cost more than a couple of dollars 😀
Gilbert says
Hi. Any chance that, for the first example of the anti-bark device (at the top of the page) you could provide a parts list so I can go to the electronics shop with it? I sent them a copy of the circuit design but they weren’t helpful. And I know SO little about electronics.
Thank you lots
Swagatam says
Hi, I have updated the parts list, but I would recommend you the last two concepts which are easy to build and fully tested.
Gilbert says
Thanks you for the advice so far.
One question: Where you have written “the indicated high power alarm”, does that mean the (piezo 40mHz) speaker or another device?
Again, do forgive my ignorance, we all have to learn somehow. I have rewired a house and had it approved by the government, but electronics is such a different world.
Swagatam says
Actually it is a mistake, it cannot be a high power alarm, since that will create more noise than the dog barking itself, which will destroy the whole purpose of the design.
Yes it should be actually a high frequency based alarm circuit which can be built using a IC 555 astable, set at 20 kHz frequency…the speaer for this can be a tweeter unit of a piezo element
paul says
Thank you for your fast reply, third one 50 meters range including 3 ics circuit.
Swagatam says
You can connect a 10 ohm 5 watt resistor to ensure it doesn’t burn…also make sure the driver transistor is not faulty or burned. Also prior to testing ensure that IC2 555 is working correctly and generating the oscillator frequency correctly.
paul says
hi Swagatam
i constructed the circuit , it works about 1 minutes after that no output from the speaker (4 ohms 5 watt)and the output transistor become very hot. and i checked the speaker that is short , why the speaker is going short. can you help me to solve the problem
Swagatam says
Hi Paul, which circuit did you construct….you can try adding a 100uF capacitor in series with the speaker.
Brandon N says
First off, super impressed by this site and the amount of work you’ve put in to it. How difficult would it bet to apply some kind of filter to the mic side so that it’s triggered by barking noises instead of just any loud noises like a car driving by?
Swagatam says
Thank you very much for liking the website! Adding a filter can make the circuit very complex. And moreover the output from the speaker is supposed to be a high frequency sound that may be inaudible to the human ears, so it doesn’t actually matter how many times the circuit gets activated and with what type of sound.
Jerry says
Well it’s spring in the Dakota’s once more. The windows are being unsealed from the horrific winters we experience up here and screens now offer the only protection from the things that go bump in the night, and those pesky dogs who insist on barking at every firefly that passes their cages. Our neighbors are refugee’s from California and come with that West Coast attitude that includes no sense of the proper application of the Golden Rule. They have two huge dogs accompanied by a little ankle nipper, together they can keep the barking opera up at least 9 hours per night, those folk don’t seem to think dogs need protection from the nights so they are out night and day in a little 6 by 6 dog kennel in their back yard. A bit of blue tarp gives the poor animals some shade. When I approach them about this problem is that No Habla Engels that they are so proud to use in a city where Spanish is not among the languages spoken, our other languages include Swedish and German, but never Spanish. So it is, I come here seeking an electronic solution to the barking problem. When I approached the deputy, he explained that the fine for discharge of a firearm in the City Limits is only 10 bucks, nearly the same as the cost of a round for my .45 however why should I have to shoot those poor dogs who are surely abused by the folks. I have mentioned it to the ASPCA but their out is simply they have no offices here in this part of t he State. So anyhow, I have considered the options, perhaps build this circuit, or another interesting solution I found by a fellow down under that involves using an Arduino, an old MP3 player, a ready built amp and some cheap 600AMP tweeters (marked but I doubt the real power) Using one of those little arduino sensor deals that detects sound and outputs a High on the desired pin to play the dog whistle sounds. I found several sites that have the mP3 or WAV files with different frequencies. Guess I will play around with both options and see which I prefer.
Swagatam says
I am feeling sorry for the dogs, they must be already suffering a lot, and they have their own problems which they cannot explain to their owners. It is the owner who must be punished, not the poor dogs. Anyway thanks for posting the comment, hope the circuit works for you.
Jimmy Haley says
how much for a diagram of the loudest dog bark stopper,,, i am super tired of my neighbors damn dogs barking at every thing that moves,,, and a list of parts needed,,, thanks,,, ole fart Jimmy in Texas
Swagatam says
the last two diagrams are very sensitive, and will respond to any sound loud enough, like the barking sound. The C2 value decides for how long the output stays ON after triggering, so it must be selected carefully. R1 decide the sensitivity, lower values will give higher sensitivity and vice versa.
Daniel Acosta says
Where I can buy the PCB?
Swagatam says
It is not available from here!
Dan Prince says
Can you built a powerful one for me? I tried 2 on Amazon and they do not work.
Swagatam says
The last two designs are super powerful versions….
Xen says
Hi,
Does this circuit work? I would like to build it as I have a major issue with neighbour’s dogs continuously barking.
Swagatam says
Hi, yes it will work if done correctly and with proper understanding! You should request your neighbor to do something about it instead of troubling the dog, which is only doing its natural duty!
Michael says
Your explanation that the Darlington will drive the speaker optimally makes sense, but I’m not entirely clear on why you are using one in the case of driving the relay. Wouldn’t any switching semiconductor do? Or was the sensitivity of the darlington needed in this case for minimization of hysteresis?
I was thinking maybe I could use one of some BS170 FETs I have left over from my respirator project (a stereo cable between the preamp in the mask and amplifier on my belt had been picking up noise from a fan in the mask used to prevent CO2 buildup, so inside the mask, I had the fan run only whenever I wasn’t speaking and used the fan’s power to bias the cable’s audio line, and at the amp had the presence of positive bias cause the BS170 to shut the amp down, so the fan (which is running when I’m not speaking) can’t be heard from the speaker. Using the BS170 to shut the amp down saved me from needing a 4 conductor cable and plugs – effectively, I’m using bias to overload the audio line with a digital function)
How much power do you think would be wanted if in place of the TIP127 and relay, I were to use a BS170 to directly feed an oscillator output to the tweeter? Even though its only in a TO-92 package, The BS170 is rated at 500ma. and 60 volts, which could give me 30 watts. I’m just not sure I can hit both limits simultaneously ( although with square waves, might that be less of a worry since it wouldn’t be a continuous assault on the device at those limits?)
I also really have no idea of the wattage rating of these tweeters. I tried the mfgr’s web site, but couldn’t even find a reference to them there.
Swagatam says
If a relay a used then the transistors can be a a simply any low power BJT such as a BC557, the TIP may be only required for driving a tweeter or a loudspeaker directly.
The circuit must be first tested with any ordinary tweeter, once confirmed then it may be replaced by a powerful one.
Michael says
Another concern comes to mind: Protecting one’s own hearing.
Even vibrations one can’t hear will still reach the inner ear, and if loud enough could still fry cilia corresponding to frequencies that one IS able to hear. The loss of the ability to distinguish harmonics (resulting in turn from the loss of cilia corresponding to higher frequencies) is the reason that people gradually (or in the case of some musicians, quickly) lose the ability to understand nuances of speech in the presence of background sounds, even though they can still do well on hearing tests (at least if such tests don’t take harmonics into account). I’ve observed this myself while watching action scenes on TV with friends if some of them are decades younger. The younger ones have no trouble making out some speech that those of us who are older have difficulty with when the background music is strong. Which leads me to conjecture that some higher end hearing aids (the ones that advertise better understanding of speech, not just amplification) may deal with this with a selective boosting of harmonics tailored to the individual, or perhaps something even more complex (although I haven’t had the opportunity to check one out to verify the notion.
Anyway, I think I’d want to keep the tweeter outside, some distance from any room I’d be in. But when testing, still indoors, some good earplugs are probably in order.
Swagatam says
Sure! no problem, safety is always first, thanks for the info, appreciate it!
Michael says
I’m concerned that the square waves from the 555 would eventually (or perhaps sooner) end upfrying the speaker. Would such a concern be the reason you’ve told Susanna “Just make sure to use powerful tweeters as the speakers.”? i.e. a powerful enough tweeter that feeding it only square waves would not present a problem?
With that in mind, what would you think of using a Cerwin-Vega LSETH2152 ? I picked up a couple of them at All Electronics for 5 bucks each last year. I’ve been unable as of yet to find their specs , but they’re 4 ohm dome tweeters with hefty magnets weighing 22 ounces each (the whole tweeter, not just the magnet)!
On the other hand, would the choice of the darlington output transistor have been to ensure that as sufficiently powerful a tweeter as you recommended to Susana wouldn’t be underdriven? Or was it for a different reason?
Swagatam says
Yes the powerful tweeter will help both the things, it will protect the the device and also ensure a louder and powerful frequency to be thrown towards the dogs, so that it is heard from some good distance. I think the mentioned tweeter should do the job.
The Darlington will drive the tweeter optimally, the main idea is to ensure that the dogs are able to hear the frequency from a distance.
Susana says
Thank you for the circuits. I’ll ask my husband to make one. My question is, I will be able to hear it?, because he tryied others and we can hear the high pitch.
Swagatam says
You are welcome! You can set the frequency at 13 kHz which will hardly audible to the human ears. Just make sure to use powerful tweeters as the speakers.
Phil says
OK– where can I buy the supercharged version. Need it today!
Peter says
What frequency is it emitting?
Swagatam says
you will have to experiment with the frequency to test which frequency deters the dog the most
Peter says
Hi,
So its variable which is necessary.
Which frequencies does it use?
If suitable i will arrange for it to be assembled.
Thanks.
Swagatam says
Hi, anything between 15kHz and 25kHz should work, but this will need to be tested with real dogs
Peter says
Hi,
Prompt replies youre providing is greatly appreciated.
Thanks.
Swagatam says
My pleasure!
Malcolm says
Hi swagatam,
Congratulations for your excellent site and specially this AntiBarking circuit.
I have a simple request if possible: Could you please provide me with a design on how to eliminate the speaker and instead include a group of at least 2 two piezo tweeters? I really need to make it as loud and powerful as possible and I,m getting conflicting suggestions elsewhere.
Thanks a lot.
Swagatam says
Thanks Malcolm, The speaker can be simply removed and replaced with an appropriately rated tweeter. The circuit frequency being very high will perfectly complement the tweeter specs and generate the required frequency efficiently.
The transistor driver will make sure the tweeter is driven with sufficiently high output. Alternatively you can replace the BJT with a MOSFET for getting more powerful output
Malcolm says
Thank you very much for your reply. I wish you all the best, sir.
Swagatam says
It’s my pleasure Malcolm!
William Ballough says
There are a lot of remote dog bark devices on the market. Because you have extensive experience in their electronics, potential purchasers of such devices would benefit greatly from your evaluation of their respective efficacy and utility. You could do U-Tube presentations and perhaps interest an investor to partner with you in making and selling those of your design, or a corporate sponsor in evaluating different brands. yourmanufacturer in making the best designone of your design
Swagatam says
Thank you for your valuable feedback, I’ll surely consider them. Appreciate your thoughts very much!
Malcolm says
I strongly support what William Ballough said above. There is a significant untapped market, worldwide, for powerful ultrasonic AntiBarking devices that really work. In case you are interested in discussing about it, please contact me in private by my email. I have extensive knowledge on this matter.
Swagatam says
I appreciate and agree with your suggestions, I will surely think about it.
JMonroe says
Malcolm, have you had any success with moving forward with promoting an off-the-shelf powerful version of the anti-dog-barking project? I agree there is an untapped market for something better than currently on the market. I think people would be wiling to pay $200 and up for something that really works.
Trishpota says
Dear swagatam
In the first circuit only ic2 stage using for permamently working is enough?
Greg Hill says
Im interested in buying one of these. Would you be willing to make one?
Swagatam says
I am Sorry, we don’t sell assembled kits in this website!
Dave says
The neighborhoods available to elderly me for health walking have many obnoxious barking dogs. I want a handy/portable bark stopper that I can use while walking; range about 50 feet.
drhiii says
Who would be able to make one or two of these for me? In Colorado.
Ken says
I’m interested in making the basic whistle. Can I run this through an external amplifier?
And just via the on/off.
Swagatam says
you can apply the output from the 555 astable to an amplifier for getting a whistle sound.
Timothy speer says
What is want a circut board that just triggers when barking occurs. Want to link to self defense dog vest. Dog barks taser set off. Other dog gets shocked while they are attacking. Was thinking taser vest. Any help would be great.
Swagatam says
I have updated the required design at the end of the post, but please do not use a taser, you can use something else instead.
Paulo says
Swagatan, can the optional circuit to increase sensitivity be powered with a 12 VDC supply as the mais circuit?
Thanks
Swagatam says
Hi Paulo, yes 12V can be used.
you can also try the first circuit from this article instead:
https://www.homemade-circuits.com/simplest-sound-activated-relay-switch/
Remove the relay and connect the collector of the PNP with the base of 2N3904 in the above circuit.
C2 in the linked circuit an be removed.
Paulo says
Thanks for the quick answer!
Paulo says
Swag,
A misalignment of the lines connecting to pins 2 and 6 of IC2 on the drawing brought me a doubt concerning these points.
Am I correct in assuming that pins 2 and 6 of IC2 both connect a single point between R6 and C5?
Thanks again.
Swagatam says
I am sorry about that, yes you are right they both connect at the junction of R6 and C5
Les Grant says
Hi, do you have a pcb diagram or veroboard layout for your dog bark stopper? Would be appreciated if you have.
Swagatam says
Hi, I am sorry I have not yet designed a PCB for this project.
Göran Kronström says
Hi!
I´ve just done a proyect in Kicad and Freecad, where can i upload the files for it?
I also took a nice screenshot of the 3D view of the board.
Brgds Göran
Ronn says
Hi Goran
Good work on the pcb.
Can you point me to a url where i can download the Kicad file.
Many thanks for your work .. Cheers Ronn
Iain Murray says
Hi Swagatam,
I’m just making this circuit, one question I have is can I mount the speaker in pvc tube to make it directional would that effect the output from the speaker
Swagatam says
Hi Iain, actually that’s a good a idea, and would prevent the sound from returning back to the MIC…… although the returning sound won’t impact the circuit, still using a PVC pipe would make the system more efficient.
Dominic says
Thank you for your help. Dominic
dominic says
Good morning,
Please provide a detailed parts list or the price for a completed kit. Dog Bark Terminator.
Thank you, dominic.
Swagatam says
Hi, you will find all the parts given in the diagram itself, here all resistors are 1/4 watt rated and all the capacitors can be 25V rated
James says
dO YOU HAVE THE DESIGN IN eAGLE
Swagatam says
sorry, I don’t have it…
Rick says
Wow, thank you for your super quick reply, will try with different value resisters & see what happens, thanks again for your excellent support to the electronically challenged like me, Rick.
Swagatam says
Sure, please go ahead Mr. Electronically Challenged, I liked this phrase 🙂
Wish you all the best…
Rick says
Hi Swagatam
I have been reading the request from Jan on how to increase the output for a 50 meter range using a 2n3055 & 100 ohm resistor, I have tried this but i think its over loading my 50 watt piezo speaker, would I be correct in thinking this? if so what do you think the output is with that setup & what size piezo would be needed? thanks for your help, Rick
Swagatam says
Hi Rick, By overloading do you mean your speaker is warming up or is the sound quality breaking of?
Anyway, you can control it by increasing the 100 Ohm base resistor of 2N3055 to some higher value, may be upto 1K or even 4k7 etc until the current is no longer able to increase beyond the specified safe limit.
Rick says
Hi Swagatam, I have finally put this circuit together & seems to be working, but I can hear the sound although quite high in pitch, also I will need to build the additional Mic amp circuit as the current one seem not very sensitive.
I would like to ask for your help as to some mods I would like to make to change its operational characteristics.
I have noticed that when activated the sounds is on for a short time period which can be adjusted by changing R5 & C3, is there a change that can be made to have it operate for as long as it is powered on? also I need to be able to have its frequency adjustable, your help would be much appreciated, Regard Rick
Swagatam says
Rick, you can do it by adding the following latch circuit between IC1 and IC2.
https://www.homemade-circuits.com/2011/12/simple-and-useful-transistor-latch.html
you can remove the relay from the design.
in the dog barking circuit disconnect pin#4 of IC2 from IC1, and connect it with the collector of the PNP.
connect the base of T1 in the latch circuit with pin#3 of IC1.
in the latch circuit preferably remove C1 from the shown positive and place it across base/emitter of T1.
Rick says
Hi Swagatam
Thank you for the info on the Latching circuit, I will give that a try, If I may ask how the frequency output can be adjusted/variable to a higher pitch as I can hear it so I figure it may not be high enough to do its job.
Swagatam says
Hi Rick, to increase the output frequency you can decrease the value of C5 to some lower value…. You can try reducing it to 470pF or 330pF and see the effect.
for getting a variable option you can use a pot for R7, but make sure to add a 1K resistor in series with this pot.
Rick says
Hi Swagatam
Thank you very much for your quick reply, will give all your suggestions a go, thank you once again, great wed site, Rick
Swagatam says
You are most welcome Rick!
Jan Van Vuuren says
Hi Swagatam,
I know very little about piezo disc transducers
I was wondering if the speaker can be replaced by a transducer. Do you think this can work?
Your opinion will be much appreciated.
Regards
Jan
Swagatam says
Hi Jan , yes definitely the speaker can be replaced with a transducer, however it will need to be complemented with a matching parallel inductor so that the oscillations can be optimally amplified.
Jan Van Vuuren says
Thank you for your reply. So how do I calculate the value of the inductor?
Regards
Jan
Swagatam says
You can purchase it readymade from your local electronic dealer…or from any online store, you just have to mention “piezo buzzer coil” and you will able to easily find it
Yousef says
Hi Swagtam
How can i make this circuit work permanent without sensing the dog’s bark ?
Swagatam says
Good question Yousef,
you can do it simply by using only the IC2 stage, that’s all….
Swagatam says
Hi, yes a tweeter would respond better than an ordinary speaker, however I was expecting an almost inaudible output from the speaker, because the IC2 is set at around 13kHz which can be hardly heard by an human, I think you might want to adjust the R/C components of the IC2 a little more to make sure that humans do not hear it but dogs do.
yes if it's a normal beep then your dog will not be impressed, it has to be something more irritating. Actually the dog will get surprised only when the sound from the speaker responds and coincides with its own barking, that's exactly when the dog might start getting too nervous 🙂
Jan Van Vuuren says
Hi Swagatam,
Thank you for the revised CCT.
Regards
Jan
Swagatam says
You are welcome Jan!
Jan Van Vuuren says
Hi Swagatam,
I am a bit confused. In your explanation you say “ use the R1/C1, and the MIC network which is shown in the last circuit from the above “DOG Barking” article, and connect the C1 end with the volume control of the linked LM386 circuit. Is this pin 3 or 5 on the LM386? Does Last cct refer to the “Making the cct more sensitive OR the main cct with the two 555 timers.
Your assistance will be much appreciated.
Regards
Jan
Swagatam says
Hi ajn, I have updated the required diagram at the end of the post, please check it out.
Swagatam says
…you ca use BC547 for Q1
Jan Van Vuuren says
Hi Swagatam,
Thank you for your reply. Does this mean that the speaker range will also be 50 meters.I read some were that the current design is effective for approx. 10 meters. I need to increase this to 50 meters.
Regards
Jan
Swagatam says
Hi jan, according to me the amplification power could be increased by replacing the speaker transistor with a 2N3055 transistor and using a small value base resistor of around 100 ohms…this will hopefully make the output strong enough to carry it up to 50 meters
Jan Van Vuuren says
Hi Swagatam,
I would like this unit to have a range of 50 meters. What modification should I make to achieve this. Also can I use a Compression driver instead of a speaker as it appears that Compression drivers are much more efficient.
Regards
Jan
Swagatam says
Hi Jan, you can try the LM386 based last circuit from this article, to enhance the sensitivity of the entire design:
https://www.homemade-circuits.com/2012/08/ic-lm-386-datasheet-explained-in-simple.html
use the R1/C1, and the MIC network which is shown in the last circuit from the above "DOG Barking" article, and connect the C1 end with the volume control of the linked LM386 circuit.
The speaker point outputs from the LM386 modified design can be finally integrated with the base of Q1 as presented in the first circuit diagram of this particular page
Swagatam says
The degradation could be due to a slow internet connections, anyway glad to know it has been rectified now and the image is now clearly visible to you.
Swagatam says
click the images to enlarge them
Swagatam says
you can use 9V instead of 12V without any modifications, but make sure the current is sufficiently high so that the speaker can be driven with the required amount of power…a 9V PP3 battery will not work.
Swagatam says
yes that's possible, you can use a pot in place of R2 and tweak to keep the opamp at the verge of conduction and make the circuit very sensitive.
additionally you can use a Darlington transistor for Q1 for enhancing the sensitivity of the unit
Swagatam says
that's great, now you can confirm the final results with an actual dog barking
Swagatam says
you are welcome, actually any opamp will work here, you can easily replace it with an ordinary IC 741
Swagatam says
Hi, That probably means that the MIC stage is not powerful enough and needs to be upgraded so that it becomes more sensitive for converting the sound signals into triggering signals for the IC 555, I will try to update the above article with the mentioned improvements soon.
Ashok Dhenge says
Sir, i made this circuit but i am facing some problems. When power supply is on speaker get some vibration continuous, no any sound but feels vibration. When i remove mike speaker vibration stop. Please help me for this. Is this vibration is capable for generating sounds for keep away dogs.
Swagatam says
Ashok, the response that you are getting from the speaker looks OK, but it should not happen continuously…rather only when a sound hits the MIC.
I think the sensitivity of the mIC circuit could be too high. try reducing C1 to 0.01uF or 0.001uF and check the response
Ashok Dhenge says
Sir, i changed C1 0.1 to 0.01uf, this time no vibration sense in speaker. When i clap for sound then nothing happen with speaker.I inspect the circuit carefully i found one short connection at IC1 3 pin to IC2 pin3 which is directly activate base of TIP122. I made correction but after that circuit is not work.
Swagatam says
Ashok, a short circuit of any kind across the ICs can damage the devices…so better change the ICs again and test.
this time do not connect the MIC stage, rather initially test by manually shorting the pin#2 of the IC to ground (momentarily) and see the response on the speaker…
Swagatam says
…sorry, correction: test by shorting R3/C2 junction of IC1 with ground
Swagatam says
you can see the pics below:
MIC
reviseomatic.org/help/e-components/Electret-mic.jpg
Speaker (tweeter)
img.weiku.com/a/001/812/KTV_tweeter_speaker_T031402__3659_7.jpg
Sarah says
Can you please provide more info about the MIC and Speaker? any part number?
Thanks,
Lee says
Is the IC555 is LM555?
Swagatam says
any 555 will work
Internal combustion engines says
dear do you have a ultrasonic circuit for elephant. in our country daily one or two people are get dead due to wild elephant. request help. i noted that elephant hearing frequency is 16-12000hz.
Swagatam says
You can easily make it by using a 555 IC along with a speaker amplifier stage, quite identical to the IC2 stage as indicated in the above article.
the frequency can be set by suitably adjusting the values of R7 and C5 …until the effective note is achieved for driving of the animals.
the range will depend on the power of the selected transistor and the wattage of the speaker, higher wattage will enable longer ranges.
Ashok Dhenge says
what is electrec mic? How to test this circuit? When mic detect dog sound at what time waves are generated?
Swagatam says
electret mic is small mic which are commonly used in amplifiers and FM hand held transmitters,
connect an LED in series with the TIP122 base whenever it lights will indicate the working of the speaker.
clapping near the mic should initiate the triggering process….
Ashok Dhenge says
in above circuit what is range of sound will be heard by dogs? also what is effect on another animal? is this circuit activate for all sound? means human noise also activate this circuit? How to make possible range?
As in our farms there is lots of peacock wonder at the time of harvesting can this circuit is applicable for this condition?
Swagatam says
the range will be around 10 meters, other animals may not be affected because they may not possess high sensitivity to sound frequencies as dogs normally have.
peacock cannot be driven using this circuit because the hearing range of birds are quite similar to the human beings except bats
sharaf says
Thanks a lot for your support and help……….
sharaf says
Hi Swagatam,
We are facing lot of problem with street dogs and those are tresspasses to the residence area, especially in night time.
So, if we use PIR the device can work only the particlar time instead of full time.
Swagatam says
OK in that case you can use the following circuit
https://www.homemade-circuits.com/2014/09/automatic-pir-controlled-fan-circuit.html
remove the relay, we don't want it here, also disconnect the emitter of the transistor from its ground position and connect it with the IC2 pin#4 from the circuit explained in the above article.
so we'll require only the IC2 stage from the above article circuit and integrate it with the PIR circuit from the given link, as explained.
sharaf says
Hi Swagatam,
If any dogs are enter to the coverage area immediatly trigger and generate ultrasonic sound to repel the dogs.
Swagatam says
Hi Sharaf,
a PIR will detect all types of living beings including human beings, so that will not work….
Swagatam says
…warm blooded living beings
sharaf says
Hi swagatam,
Can you explain the circuit with PIR sensor instead of electret MIC.
Swagatam says
Hi Sharaf, for what application do you intend to use it? please provide with more details so that I can understand it better.
CrazyLarry5000 says
If a powerful enough speaker and amplifier are used, can this frighten a dog enough that it would run for it’s life?
I have dogwalkers that let their dogs go to the bathroom in my yard and I would like to frighten the dogs out of the yard without using firecracker wave files that everyone else can hear.
Swagatam says
Yes, that may work. You can also try a loud a gun shot sound