Posted on 06/12/2012 6:19:07 PM PDT by VA Voter
I need some help giving pest Grackles a hot foot. My wife hates the Grackles so much she wants me to take down the bird feeders altogether but I like all the other birds, so I designed an electrical hot foot for the bottom of the metal feeder that by all I know about electricity should work, but it doesnt.
The concept is simple: two parallel 16 gage non-insulated copper wires ½" apart, 1/4 above the bottom of the feeder, and attached via wire nuts to the two wires of a modified extension cord. When plugged in, the Grackles are supposed to step on both wires at the same time and, wala, the hot foot and they then they arent supposed to come back.
Its a little more complicated with insulation, stability and placement but not much. Definitely low tech. I have tested the wires with a light bulb that lights up when touched to the wires. I do know enough not to test it with my finger.
The Grackles have taken over the feeder for most of the day and bully all the other birds away so I only plug it in at my end when they are on the feeder.
The problem is that the Grackles walk all over both hot wires without so much as a tingle. The design inspiration is from a very similar concept from Bird-B-Gone.
This exhausts my very long ago HS electrical expertise and likewise that of the associate at Home Depot, who got a huge kick out helping with the parts: alligator clips, plastic hose for insulation, electrical tape, portable GFCI switch, wire nuts, etc.
What am I doing wrong? Thanks in advance for any help and for all the wise cracks this is sure to attract.
I am a retired electrical engineer....I agree with raybbr in that you need higher voltage, if for no other reason than the bird's feet may have extremely high natural resistance, and the Bird-B-Gone specs pretty much confirm this...they use 800 volts!!
Another poster has suggested using a doorbell transformer wired backwards...this very knowledgeable individual probably knows the impedance of both the input and output sides of the transformer and the resultant voltage when you apply 120 vac to the output side of a 25vac doorbell transformer. The normally used input side would now put out a much higher voltage, as he indicates.
Try it; good advice.
If you can get an AC voltmeter, put one test lead on one of the wires and the other lead to building ground. The wire that reads 120vac is the hot side.
The other wire will be the neutral, and will read much lower.
On a 120vac plug the wider of the two blades should be the white wire and connected to the neutral buss. The narrower one should be hot and connected to the black wire. Round is connected to ground theoretically if built since the late 60’s or so.
My guess there is not enough resistance to make it work.
I’m both an EE and master electrician - DO NOT try to use 240V!!!! Too dangerous......
The problem, as others have said, is not amperage, it is voltage......as others said, get an electric fence power source - or the Bird-b-gone.....they are designed to safely do the trick.
But your wires must be close enough that the birds feet touch both at the same time.
As their foot hide is probably tough, it is likely more an insulator than a conductor, but it should work.
One can run 120v (DO NOT DO THIS) between thumb and finger ONLY if both are very dry, and all you will feel is a slight tickle. This is likely what is happening with the birds.
Wet hands, go from hand to hand so amperage goes through your heart - and the same voltage will kill you quickly.......and obviously - don’t do this either.
The problem is that the Grackles feet are essentially non-conducting.
.
First the bird must contact both supply wires or the HOT and Ground- At the same time. Otherwise no current and no shock.
2nd A higher voltage is much more effective in that it will overcome resistance much better- causing a greater current or shock in this case.
As someone here suggested then you best bet is probably an electric fencer unit. It will provide a higher voltage and will also pulse on and off so that if a human comes in contact with it then they will have a chance to let go.
Yeah, those grackles have dry scaly bird feet that don’t conduct very well. The current is so low that they’re barely even getting a tingle. Heck, they might even like it.
Not fair, you owe me a monitor!
Funny :>)
Two things:
1. If the Bird-B-Gone works, use it. Unless you KNOW what you are doing, you’re going to get someone hurt.
2. From their website: ***If placed outdoors, the direct charger must be protected in a waterproof box. *** Why would anybody in their right mind have one INDOORS???
Try this gadget:
They supply high voltage but limit the current to a non-lethal level. Cattle hide is high resistance, like your bird's feet, and high voltage is needed to overcome it. A fence transformer will help keep you from electrocuting yourself if you make a mistake.
Wire the output of the transformer to the wires on the feeder, and plug in an extension cord at the house end to activate it for the nuisance bird, deactivate for desired birds, reactivate for squirrels.
>>>Why would anybody have the direct charger indoors?<<<
The “direct charger” conducts the electrical charge into “up to 500 ft. of electrical track” which presumably conveys the shock to the birdies.
The charger is what plugs into the wall; it ain’t the part what fries the fowl.
I suspect that's the trouble. I've been told that heavy callouses on the human hand actually lessen accidental shock; the callous acts as an insulator.
Increased voltage will overcome this natural insulation but rather than spending money on a fence charger, try a conductive gel like vaseline on the wires. Fair warning: if this actually works, you'll probably KILL the bird.
Don’t use house voltage. Very dangerous thing to do and setting yourself up for major legal liability. Go to Tractor Supply or a farm equipment store and get a fence surger. You’ll have 5000 volts that will be far safer. The thing is for any thing to work the intended critter has to be on the hot lead and touch ground. Birds roost on utility high voltage power lines. How? Because they are sitting on one conductor and no ground..
My father liked to feed the song birds at the cottage but the larger birds keep eating all the feed and chasing the smaller birds away......he built a bird feeder with a loud bell under the foot bar...the smaller birds were not heavy enough to trip the the bell (buzzer) but it caused the larger birds to fly away when they tripped the buzzer. Pretty soon the larger birds didn’t even come around anymore. It took a little observation and trial and error to get the balance just right....anything as large as a robin got scared off the feeder..
About 2 weeks ago, I grabbed ahold of a computer power supply that was shorted and hot.
I knew it was shot but didn’t know it was shorted to the case. Sittin on my kitchen floor, good thing I wasn’t grounded.
Still, the B! slapped me good! Real good!
I think you’re right about using a conductive gel. Probably not vaseline though, which I doubt is conductive. There are specially made greases that contain carbon or metal particles that are conductive. The only problem is the good birdies would get their feets greasy.
If the two wires are only 1/2” apart, the birds may be bridging the gap with only one foot, which means the current is going across the tough skin on that foot and not up into the bird’s body for a good jolt - try putting the wires like 1” apart so there’s a chance the bird will get each foot on one wire, which should get his - or her -attention......
A high impedance fence charge will work because its output is 10,000 to 20,000 volts DC with very small amperage. It will require the high voltage to get through the bird’s tough skin on its foot. Don’t need high amps unless you want to fry them. The high voltage will knock their socks off.
Hot and Ground wires will need to be not too close or it’ll spark. I’d guess 3/4” separation.
Trying this with 110 or 240 vac is damned dangerous and probably not effective on the birds.
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