KEMO Ultrasonic Power Cannon Building Block

does not work on dogs, cats at all, they barely flinch. probably need to hook it up to a high power amp with high capacity tweeters, then should work.

This is my second bazooka. Works great. The neighborhood dogs are becoming well trained to stop barking - much quieter. Have it connected to a remote so it’s only on when the button is pressed. When a dog barks press the remote for 5 seconds or so. The dogs soon learn that barking is unacceptable.

Works great...the mutt next door starts frantically yipping and trying to get inside its' house!

I got the unit to work, but it pulsates once every few seconds. The affect on the dogs is zero. They notice it, but don't care about the noise at all.

It works as advertised...first time.The photo shows Rev 1 of my project.The oscillator only has the one frequency and its usefulness is limited.I added a USB port to power an external oscillator with its own amplifier that is variable and can run on the same battery.The speaker is in a caulking tube attached to its plunger so I can place it in differing places based on frequency/wavelength.Practical? Useful?It's clunky, over engineered, and not very practical. It was designed on the fly and was a LOT of fun making it.The overdesigning of Rev 2 is in underway.It will have double barrels and 2 seperate Kemo oscillators operating independently and on different frequecies.The variable ones are much more useful and less clunky since they can live onboard.

1. BUY THE RIGHT PIEZO speaker. I can't say that enough times.2. Yes, it's a .5s burst every 5s. So buy more than one, and stagger them! Yeah it might get expensive. But what do you want? Something that works, or another gadget that doesn't?I have 3 of them now and I run them staggered; this isn't hard if you know how. I don't want to add any more for fear the cannon will get heavy, but that's probably unjustified. What really gets heavy is the battery pack, although LiPo's work and... google is your friend. I'm not going to give a tutorial, again google is your friend. They're hooked up to a pair of the piezos that I have in my "double barrel" shotgun made of 1" PVC piping. The extra set of electronics/passives and the amps themselves are in the "magazine."I use it to shut up a dog that's about 200 meters away. It works EVERY time. the dog will run around to the other side of their barn and stay there for at least an hour. On the other side of my property is another pair of dogs- a Marmaduke dog and a bulldog, both very stupid animals. It takes a few rounds to get them to leave, but they do. Works every time. (I'm a dog lover, btw, so don't get all wierd on me. (I have two myself but they come when they're called and shut up when I do call them. So this is really about the owners, not the dogs.)The cannon will also work on a variety of other animals, too. Birds, for example. Specifically, chickens- including roosters. But it doesn't last long and it can't be used too often; they get used to it pretty quick. It WILL scare wild birds away though.This rig is not for the noob. Know what you're doing and it'll work. Last little comment: you absolutely MUST use the right speaker for this thing. MANDATORY. The last one I bought came with the right speaker; the company must've gotten wise to this. Don't listen to anyone who says the thing doesn't work, I'd bet it's because they got the wrong speaker for it. (Yeah yeah ask me how I know.)Anyway, 5 stars because it's awesome, with 3 for ease of use/sturdiness and 4 for value.

This is no cannon. I used the instructions on the Kemo website to build a cannon. I have experience with electronic components and took my time assembling this thing. I Used a 1 5/8 ID 30cm long pipe with a cap on the back end. Piezo was mounted inside the pipe. I checked all connections with my meters, all working. Tested at close distance < 5 meters and animals didn’t like it. But this is advertised to go 300 meters. So tried neighbors dogs maybe 50 meters away and didn’t even phase them. I would not recommend for a “cannon”, but maybe as a close range deterrent.

I really wanted to like this product. I would have been happy if it was either ultrasonic or high powered (preferably both). The one I received was actually 11,500 Hz and ~50 db. I can confirm it does buzz for 0.5 sec every 5 seconds. Didn't bother my cats at all, who were lounging around the house.