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Rat-Zapper?

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by HarveyH42, Apr 16, 2008.

  1. HarveyH42

    HarveyH42 Banned

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    A few days ago, my dog found a rat living on our back porch. I shot at it with an airsoft gun (only thing I had handy), it took off and the dog chased it over onto the cat-dude's property (yeah, I'm a really good neighbor). Sprayed some ammonia around to discourage it's return. Well, it was back this morning, shot at it some more, but need a more permanent solution.

    I don't want to use poisons, well yeah I do, but it wouldn't be the best idea in this situation. It's outside, so there's the potential for it getting scattered about, dog might get in it. Neighbor's cat (you'd figure one of those mangy little bastards would take care of business, he currently has 11 cats). I like the squirrels, they help keep the oak scrub under control. Spring trap wouldn't be much better. Which only leaves live traps, which would most likely just be another piece of junk to join my clutter, besides, I don't want a live rat, which I'll have to kill anyway, what's the point.

    Being I spend a great deal of my spare time tinkering with electronics, this would be the natural choice for taking care of the rat. First, I was thinking a disposable camera flash board, and just soldering some leads to the capacitor. Figure on around 250 volts, but not sure if that would be enough to actually kill a rat, maybe enough incentive to find a new home. Battery life, might not be so great, figure a 'D' cell instead of a AA might last a couple of nights. Thought about hooking through a solar yard light instead, since it only need be active at night, little bit safer for dog and squirrels (cats are just a bonus). Still I wonder if there will be a heavy draw on the battery after the capacitor is charged, or very little (won't be triggering the flash).

    Failing that, could use an ignition coil solution, a little bit more construction time, although a good use for the 12 volt SLA that should be here Friday.

    Also have 15 large 95 volt capacitors (bigger then 16 oz beer can), but don't have a charging circuit.

    Figure on running some 24 gauge stainless steel wire over some aluminum plate in the area I saw the rat. Figure it won't be able to avoid contacting both, and reasonably out of reach of the dog.
     
  2. mister_e

    mister_e New Member

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    i used ignition coils myself for some rats & skunk... works pretty well :D
     
  3. audioguru

    audioguru Well-Known Member Most Helpful Member

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    I have never seen a rat. There are squirels, rabbits, racoons and skunks in my neighbourhood. Closeby there are deer and foxes.

    Stop feeding the rat then it will go away to another place where it is fed.
     
  4. dave

    Dave New Member

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  5. killivolt

    killivolt Well-Known Member

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    Train the rat to recover objects from the neighbor's house.
     
  6. mneary

    mneary New Member

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    The rat is at your house because he doesn't like cats. So borrow some cats and bless your other neighbors with the rat.:D

    Seriously, anything dangerous to the rat will also pose a hazard to the squirrels.:mad:

    If you trap a live rat, you don't need to kill it; just release it somewhere more appropriate.
     
    Last edited: Apr 16, 2008
  7. highveelocity

    highveelocity New Member

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    If you want to buy it retail, there already is a product called the Rat Zapper. I have 2 of them myself, but it eats batteries, so I stopped using them. I guess I could hook up an AC adapter for them.
     
  8. nickelflippr

    nickelflippr Member

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    There was a feller that ran a Circuit Cellar article about trapping rats at his place of work. Really involved network, with leds and such to know if a trap had been sprung. He live trapped them, so maybe no help. Would not want to be accidently bit by one of your beer can capacitors.....Yipes!
     
  9. HarveyH42

    HarveyH42 Banned

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    The neighbor with all the cats, is the food source. He feeds everything, birds, squirrels, stray cats... Surprising this wasn't a problem sooner. His house is up for sale, so maybe that will end. There are two other properties that aren't in use. One is being worked on (been a couple of years), huge piles of construction crap, probable the breeding grounds. Maybe I should just get some traps. So far it's just been the one rat... Going to wire something up this weekend. Kind of like to the solar powered idea, since it'll only be active at night, and safer for everything else.
     
  10. killivolt

    killivolt Well-Known Member

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    Get a night vision camera and catch it on film. The send it to funniest home video's. Who knows maybe you'll get some cash back for all your trouble.

    Watch out for those (Protective Animal People) they might put a contract hit on you.
     
  11. Pommie

    Pommie Well-Known Member Most Helpful Member

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    Just get some traps and put them where the dog can't get them. If you get the humane traps then just drop them in a bucket of water - 5 seconds later no problem. Easiest is an air rifle.

    Mike.
     
  12. HarveyH42

    HarveyH42 Banned

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    I just got through stringing the stainless wire, going to hook up a camera flash later. Figure I'll just power it up when get up to walk the dog before work. Got a hunch a lizard or two will get zapped, already climbing on it. If I can find my tripod, maybe I'll setup the digital camera and shoot some video. Have checked to see if its IR sensitive enough though.

    Was going to shoot at it with a little pistol crossbow, but fortunately the string broke. Would have been a bad idea, if it bounced back at me.

    Anyway, the wire is up, so I can hookup anything to it. If the camera flash is too weak, likely go with the ignition coil, have several circuits. Would like to find an easy way to drop the 110 VAC down to 70-80 volts DC to charge up one of those big capacitors. Kind of curious to see what it would do to a beer can, when I need to discharge it.
     
  13. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    You're in America! - the gun capital of the world - airsoft guns are no use, get a decent air rifle, that will kill a rat no problem.

    Or (as you're in Florida) get an Uzi and use that! - I've seen CSI Miami :p
     
  14. audioguru

    audioguru Well-Known Member Most Helpful Member

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    Never mind a machine gun. Use grenades to "remove" the rat.
     
  15. RODALCO

    RODALCO Well-Known Member

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    I have killed mice but it should work with a rat as well.

    Mains voltage 230 Volts. limited via a 25 watt lamp and rectified to DC via a bridge rectifier. DC is more effective.

    Use a dry wooden plank or pvc and put copper strips on it.

    Bait in the moddle on a pin (cheese, meat)

    Phase to lamp and rectifier, than + strip, -ve, next + strip, -ve, next + strip.

    Rat will eat food. ZZZZAAAAPPPP rat dead and lamp on dimly, and smell of dead rat. It works.


    SAFETY!! This is mains voltage and will kill. so the RAT trap should be in a safe location away from children, cats etc. Put a heavy crate over it with a hole just big enough for the rat to fit through.
     
  16. xl5

    xl5 Guest

    Rats

    A decent airgun will dispense with the bugger but maybe your just a bad shot.

    On reflection get yourself a Thompson SMG can't miss with it. Aim just before the rat or cat's paws as

    a SMG will on firing start to rise whether you want it that way or not

    if you want to get the cat as well as the rat... the sound from this gun goes like this!

    Rat-atat-cat,! problems solved.
     
    Last edited by a moderator: Apr 20, 2008
  17. HarveyH42

    HarveyH42 Banned

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    I wired up a camera flash yesterday, but didn't use it. Was a little concerned that the capacitor kept charging past 300 volts (rating of the cap). Stopped at 310 volts. Not sure if it would have stopped before exploding. Added a second 160 uF/300 volt cap in parallel, hoping the charge would slow a little... didn't. Did blast a small hole in the bottom of a beer can when I discharged it though. Wondering if I took too much stuff off the flash board. I stripped it down to the essentials (PCB was cracked, traces broken around the flash tube and neon bulb). Guessing the neon was the limiter, should probably figure out which resistor, and solder it back across the caps...

    Soldered some alligator clips on a power cord, figure if that fails, I can try 110 VAC. I've got a couple of tiny 16 watt inverters, that run off 9.6 volt battery pack. They're for charging cellphones, Ipods, and stuff. Should be relatively safe. Only got about two hours with a string of white LED Christmas lights.

    Bought a $5 lamp dimmer at Walmart, figure I'll look up the ignition coil circuit we had here a couple of weeks ago. Pretty sure I had some low value start/run capacitors, don't remember the voltage though.
     
  18. Boncuk

    Boncuk New Member

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    Rats

    Why mobilize an entire army for a few rats?

    Rats and mice have one thing in common: They dislike high audio frequencies.
    Build a sweep oszillator covering the frequency range from 16 to 30KHz. Use an amplifier delivering approx. 10W pure sine wave for the output and use four speakers for equal sound distribution.

    No problem for people because their audible sensitivity starts deteriorating at 14KHz normally.

    I know from experience that there were neither mice nor rats within a radius of 10km around a German air field where they used jet trainers of the type "Fouga Magister", a twin engine airplane with engines as big as a honey bucket but with extremely high turbine rpm. (80.000 to 100.000) causing a high pitch tone.

    An alternative method is burrying some beer bottles with different water levels in the ground with the bottle neck in the air. The wind will convert the bottles into organ pipes which mice, rats and an animal which I don't know the name of (digs through the garden and leaves huge piles of soil, German name is "Maulwurf") don't like either because of the frequencies.

    Both methods work well where the latter requires wind.

    Try that method instead of setting up your neighbors with the sound of a Bazooka. :D

    Boncuk
     
  19. ReallyConfuzed

    ReallyConfuzed New Member

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    Your not by any chance in the Tampa area?
     
  20. HarveyH42

    HarveyH42 Banned

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    Saint Cloud...

    Boncuk, thanks for the suggestion will keep them in mind, but this isn't an infestation, just a single rat (for now). Not too sure I want to try the sound stuff, my puppy might not like it much. He's just about a year old now, just figured out how to bark (kind of weird). Fortunately, he only barks to alert me, don't want to encourage more.

    Anyway, put a 1 meg resistor on the neon, seems to at least slow the charging once it lights. So hooked it up outside, and will flip the switch in an hour or so. Hopefully, that will be the end of it. Got some new toys to play with.
     
  21. HarveyH42

    HarveyH42 Banned

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    Ran this thing for two nights, off on 'C' battery, neon light was off this morning. Guessing the battery is spent. It was an old, cheap, off-brand so not too bad. No dead rat hanging off the wire. The dog wasn't finding anything of interest on the porch (yes, I discharge the caps, before letting him out). Hopefully, the rat moved on. Either it's none lethal, or the rat was only injured. Wonder what it would do to the male cat that sprays in my carport...
     
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