Instructables

How can I make a simple ultrasonic dog repeller?

I have been chased by some neighborhood dogs while biking in the last few months, and I need some defense. I don't like the mace or whatever sprays, and I certainly don't want to hit them with anything. I know there are some ultrasonic gizmos but they are awfully expensive. I have found some ultrasonic (25KHZ and above) transmitters at Mouser, and I was wondering if anyone could help with how to make my own portable dog stopper. Please Save My Ankles!

ulavenger8 months ago
Do a Google search for: dog repellent electronic circuit
kbharatiya10 months ago
i have no experience in making electronics or boards, can i still manage? to make 1? i need to gift it to my fav chicken roadside eatery
fbj1 year ago
pyper mentioned 555, this also appears 555 timer at Electronic dog repellent project http://electroschematics.com/1026/dog-repellent-circuit/

This link has 25 interesting posts and schematics + further links
http://www.edaboard.com/thread10588.html




hatamata5 years ago
have a look at below link, I built this ultrasonic whistle to train my dog but I discovered it makes him go away with a look in his eyes as if he was telling me why to you want to heart me?, I stopped using it on him but I think it will drive other dogs as well away:
http://www.geocities.com/tomzi.geo/whistle/whistle.htm
foile hatamata2 years ago
GOOD MORNING,
I TRIED TO FOLLOW THE LINK YOU SHARED HERE BUT IT DOESN'T EXIST ANY MORE. IS THERE A WAY I CAN FIND THE INFORMATION YOU HAD THERE?
THANKS FOR YOUR TIME.
RAFAEL.
colin555 years ago
The biggest problem is getting a piezo diaphragm that will produce an output at 25kHz to 40kHz. Most piezo diaphragms fall off at this frequency. You can already buy these units at trash and treasure markets for about $15.00 to $25.00 The piezos are almost impossible to buy.
pyper5 years ago
555 driving a transistor driving one of them horn loaded pizo tweeters used for PA systems. They have a very high impedance so you shouldn't really have any trouble driving it off some batteries through a small transistor. Stick a potentiometer in the R C timebase thingy and you can vary the frequency.
yes take a small ipod speaker rub honey on it and play the Sesame street theme song at half volume trust me it works
darryllicht (author)  scotchtape1105 years ago
Please post a video, because I would love to see it work.
I looked this up recently and from what I found you need an oscillator which creates a frequency of 16-22khz (thanks wikipedia). I was thinking a piezo buzzer (or a few of them) would work as a speaker. I wanted to make one with like 10 of them with a frequency sweep that varied between the 16-22khz range. Probably would be bad for your hearing too even if you couldn't hear it. There are MP3 and WAV files online with these sounds created. I was thinking about using one on my phone as a ringer. It would probably make a good iPhone application make a slider that shifts the range between 16-22khz on the touchscreen (apparently different size dogs are sensitive to different frequencies).