The Portable Dog Killer

Ok, first off, this does NOT kill or harm dogs.  Just annoys them.  The device was created by Steve Gibson, one of my idols, when he was 12 or 14.  He is a computer security expert and programmer, host of the Security Now podcast from TWiT and developer of the hard drive repair program Spinrite as well as many other awesome stuff.

In short, the Portable Dog Killer, or PDK, was made to address a problem of a dog who would bark and scare people.  His solution was to make a focused sound generator set to the tune of 16 KHz.  Human hearing is 20 to 20,000 Hz, or 20 KHz.  The tone is low enough he to hear it to make sure it worked, but high and loud enough that it irritates the dog.  He succeeded to train the dog to stop charging the fence and scaring people.  Of course, being a middle-schooler, you can bet he took it to school to show his friends.

This is where the PDK catches my attention.  He and his friends at school would point the PDK at seagulls and fire!  The seagulls reaction, according to Steve, “what [PDK] did was it nearly knocked the seagulls out of the sky.”  Eventually the seagulls learned to stay away from the beach.  He talks some about how he built the device, including the most important part, the 555 timer.  Looking for the 555 timer has found me both how to wire the 555 timer in general to make a tone or flash lights, as well as full plans for the PDK.  More about that plan, the PDK 1.5 in the next post.

You can listen about it at here (21MB), or read the transcript at here.  The episode is 281.

From the guy with his eye on the sky, Travis...the camping lifeguard

Lets go Hunting

Last week or so, the beach I lifeguard at, Bayview Beach in Ashland, Wi, was closed due to high e-coli levels.  Part of the reason the e-coli levels were so high was due to seagulls and their poop.  When it rains, their poop, and everything that is in it gets washed into Lake Superior and can raise the e-coli.

They tend to hang out near Bayview Beach as we have wood pilings that they can sit on to rest and a beach and two grocery stores to get free food from.  People also like to feed them, which trains them to come over more.  In the next post, Seagull Hunting, I talk about seagull training.

Since I went hunting, I have gotten a bit obsessed with shooing seagulls, I am going to break off this topic from The Camping Lifeguard.  This blog is going to be all about repelling seagulls, including a Seagull-People interaction simulator, and hopefully building the “Portable Dog Killer”.

One last thing.  During all of this I do not condone the harm or killing of seagulls. Anything I say or do or suggest is only for repelling seagulls.  If any harm does come to a seagull its either by not moving out of the way of my bike, or having a heart attack from being scared too much.

From the guy with his eye on the sky, Travis...the seagull hunting camping lifeguard