Pest control - Bark Free

[daveob]

Can anyone please tell me where I can get an electronic Bark Free device, preferably in Durban area, and pref. today !!

It is an electronic device that emits a high pitched ( 18 to 25 kHz ) tone when a dog starts barking. Completely safe and does not harm animals.

[Martinco]

Dave,
I checked out a You Tube clip and this clip claims that this device does not work. Do you know if it does ?

[daveob]

Have seen a number of positive posts on the net.

Honestly, I am prepared to try anything at the moment.

[AndyD]

It is an electronic device that emits a high pitched ( 18 to 25 kHz ) tone when a dog starts barking.

Go for one that emits in the range of 300hz - 2.5khz to piss the dog owner off instead

Seriously though it would be very easy to build an oscillator using a 555 timer, half a dozen small components and a nice big juicy piezoelectric speaker. If you build your own you can play around with the frequency to find the most effective range and it will work out cheap as chips.

[daveob]

Thanks Andy

I have recently got an Arduino board ( I have 12vdc and 5vdc at the board location ) which has digital and analog ports, and PWM on some output ports, but wouldn't know what piezo to get or how to wire it up.

Any ideas ?

Will be going to Durban in the morning so could get supplies from A1 radio electronic supplies.

[AndyD]

Most piezo's should operate up to 20KHz but that's at the upper end of their capabilities without getting into piezoceramic composites which are used in specialized industries and start getting expensive.

You can try this one from RS Components which is quite high output but not cheap at nearly 90 bucks. There's others to look at here as well though.

The oscillator below should be somewhere close to 20kHz and it's about as simple as they come. You're kinda limited by the output directly from the 555 which is about 200mA so if you need more umph you can just add simple amplifier stage using four transistors as a voltage doubler.

[daveob]

Many Thanks Andy. Am off to the store with a shopping list and will have it all on a breadboard by lunch time. looking forward to a bit more sleep tonight.

[AndyD]

Good luck, I would get a few values of resistor or even a variable so you can substitute the 6K resistor and try different frequencies. The 5nF cap is critical, rather buy a good make with a closer tolerance as the output frequency is also dependent on the accuracy of this 5nF value. I don't know if you have an oscilloscope but it's going to be difficult to check your frequencies without one, let me know how it goes.