DIY Electric Fence Circuit

[@markhkaye]

The circuit that is shown starting at 0:37 is missing three things: Pin 4 should be wired to the positive supply (pin8), a 0.01uf capacitor should be wired from pin 5 to ground (pin 1) and a 1N4007 diode should be wired from the drain (the lead of the mosfet that feeds the coil, the 15 ohm feeds the gate and the source is wired to ground) to the coil with the cathode to the drain and the anode to the coil. This will protect the mosfet from induced voltage in the coil. I also placed a 2K ohm resistor and a red LED from pin 3 to ground (cathode of the LED to ground) so that I could see the pulses. This is definitely an option.

[@souissihadjdz]

Did the plan you are talking about succeed?

[@francomongillo]

It is not possible to read the first capacitor on the left in the diagram, what value does it have?

[@janfurstenberg4454]

Hi can you please make a drawing that it can be more clear please

[@douglasflores1462]

@@francomongillo Maybe it is 4700µF instead of ohms.

[@TheTubejunky]

Basically a 555 pulsed flyback driver. I love those IC's! I made a strobe light from one using a 5v relay on the output and an 8 led flashlight. I wired the relay to the flashlight switch terminals, used a potentiometer to control the pulse frequency & It was awesome.

[@1227air500]

The old fence charger I had around the chicken coop had just quit working and I was ready to buy a new one, but then I found your wonderful schematic. I had to make lots of part substitutions from your original design, with parts I had laying around, but son-of-a-gun if it doesn't work great. And it cost zero! I added a 120k resistor and LED across pin 3 on the 555 and the input to the transformer primary and that gives a visual indication at night from a distance that the charger is working. I Ty-rapped everything inside of a clear plastic mayonnaise jar and it looks pretty weird. But it works GREAT! Thank you for your design! Lloyd

[@clintm2010]

Hi AirgunLab. Are you happy to share your schematic with the substitutions you made? Thanks

[@1227air500]

@@clintm2010 Sure. I didn't change the schematic, but I did substitute some parts, as follows. For the power source, I used a 12vdc plug-in wall wart charger. I tried a 9volt battery but it didn't last very long. For the 4700uf 16v cap, i just wired two 1000uf and two 470uF caps in parallel to get about 3,000 uF. I used the 1Meg,18k, and 15 ohm resistors, 555 timer, and 1 uF cap as shown in the schematic, without change. Instead of the 1N4148 diode, I used a 1N4002. An IRF740 mosfet was used instead of the IRF244. Instead of the .33uF 250v mylar film cap, I used a pair of 250v 104 mylars in parallel to get .20uF. After trying unsuccessfully to find a good substitute for the automotive coil, I ended up ordering one from Rockauto parts for only $7.67, pn CUC12. I was ordering some other stuff from Rock, too, so the shipping cost wasn't a factor. I added a 12k resistor in series with a white LED, and connected them between the gate of the mosfet (where the 15 ohm resistor hooks to it) and the drain of the mosfet (where the negative primary of the ignition coil connects). That flows enough current to see a dim flash in the LED each time the coil is pulsed. Looking at my charger now, I see that I also installed a small 0.1uF ceramic cap across the - and + primary terminals of the ignition coil. Not sure why I did that and it might work fine without it. Just a note, all of the substitutions were made so that I didn't have spend any money on this project. I guess spending $7.67 on the coil is ok. This charger is powerful. With the 12vdc wall wart power supply, it gives a healthy blue spark over 13mm long. Be careful! I haven't found out what the weak link in the circuit is yet, because it is still working just fine. Again, thanks to Ludic Science for his well done video. Lloyd

[@1227air500]

Correction, that is a 120k resistor in series with the indicator LED, not a 12k.

[@clintm2010]

@@1227air500 Thanks a lot. I still have to order two items and then try it out. I will be using a 12V DC rechargeable solar battery.

[@nandunsk4624]

@@1227air500 sir, can i use 12v 300ma supply? is that enough?

[@martinshishkin1246]

Thanks, work very well. just to people who are not pro the left element is 4700 micro F/ 16 volt not Oms.

[@brysongore7607]

Thank you for a really interesting video. You presented some very useful points. I have been around electronics all of my life but hadn't thought to use a car coil for this purpose. Love the ubiquitous 555 timer of course! All the best to you.

[@mommieme7]

Love it, I have, at this time, 4 fencers and purchased new all 4 of them would not even tickle a goat much less a horse unless the horse sticks her nose on it I have tried coils before but was only setting them up on the hot lead out of the fencer.

[@shawncalderon4950]

This is one of my favorite channels!

[@CliveChamberlain946]

A safety and power efficient improvement on this could be a 556 split into an astable driving a monostable (maybe every 2-4 sec. a big pulse). The 4700uF cap should be close to the inductor, and power for the 556 should be via a 1N4007 diode on the supply rail to protect it against back-EMF.

[@electromagic3111]

Hi do you have whatsapp i have some questions (a lot)😉😊

[@edwardsooy3586]

Hey Matt do you have a diagram of your electric fence? can you share with me pls I need to make mine.

[@BrunoGaspar5]

@@edwardsooy3586 Hello, did you get any help? i'm trying to build this circuit but I wold like to make soma changes

[@TheRealMonnie]

Excellent suggestions, Cliff. To Clarify, I think the diode should be to power the coil, not the 556. We want to prevent back emf from reaching the 556. Also, I think we should have a resistor in series with the 4.7mF cap to create an RC Snubber.

[@leblancmeneses3650]

I have have a 120 volt to 12 volt transformer and would like to use it instead of the oscillator is there anything I should consider when doing this? I don't know how 60 hz from the transformer compare, to the frequency of the oscillator, also the amperage on the secoundary of the transformer is 10 amps

[@MrHeavensoverrated]

Lads.. Keep trying to nick my bike out my shed.... Ty.

[@graememorris7820]

I built this circuit. It works well. Thank you .

[@erasmosolis1963]

Really, is it working... For I've noted that there's a lot of comments in which it's not working /functioning... 😌😔🤪

[@ranveeradav1402]

How long is ur fence? Do the voltage differ on the length of the fence??

[@theassamknowledge6843]

@@ranveeradav1402 yes, the intensity will vary with the fence length. You can connect the positive terminal in various parts of the fence to avoid this problem

[@graememorris7820]

@@erasmosolis1963 It has worked for over a year 24/7

[@salumkaka491]

Nice project, can you list all components with their specifications please

[@teku3985]

Mate the components specs were listed on the schematic, and tbh when dealing with these types of electronics the specs aren’t really that important, as long as you don’t put a 10 volt cap in a 10,000 volt circuit that is some extreme smooth brained shit.

[@joeyysossa4144]

Great video...exactly what I was looking for.thnks

[@danhillsablas9121]

@Ludic Science list of parts please. Is that 4,700 uF electrolytic capacitor? Can I use lower than that?

[@baileymoody3916]

I would put the ignition coil in series with a cockroft walton multiplier.

[@douglascolman4501]

Your first rung shows 4700ohm 16v. Ohm is resistance but is drawn as a capacitor? How much current at 12vdc will this device draw in 24hours.

[@margaqrt]

Nice video. However, I've experimented with different variations of these 555 ignition coil drivers, they work pretty well. That is of course until the 555 gets fried from HV feedbac into the positive rail. They fry 555s all the time. Do you have any ideas for improvements that would isolate the 555 from HV feedback? Maybe use of an opto-isolator or something similar? Thanks.

[@dale116dot7]

Transient voltage suppressor across the power rail, try a 1.5KE18, in parallel with the 4700uF capacitor, and use something like a 78L09 regulator to feed the 555 timer’s power. The TVS clamps the voltage to no higher than 30 volts. A 555 would still blow up with that spike but the 78l09 won’t. Use recommended capacitors around the 78l09. Also, add a 12 volt zener from gate to ground across the MOSFET. You can also use an ignition clamped IGBT in place of the MOSFET, but do make sure it is meant for ignition coil service, not the usual motor drive versions that are not clamped.

[@davidbolha]

Now we just need some Sheep & a fence. 😅😎

[@PapaWolf]

You can get fencing at any hardware store like Home Depot or the like. The sheep you can find out in public anywhere yelling at people who aren't wearing masks or social distancing.....

[@davidbolha]

@@PapaWolf 😃🖒👌

[@rachelhudson4662]

I'm going to make this to stop people pulling up my plants in my front garden. The plants are not expensive but well established. I'm on a low income and resent people thinking it's fun to spoil my floral display. It's for the benefit of everyone.

[@roverman985]

Should plant the people that's doing in that same garden.

[@kimo4646]

Just use a motorcycle indicator blinker as a driver. It works

[@ksrawanlab5986]

This circuit can make from relay also

[@shubhamzingare4433]

can i use this for my farm

[@petqu_861]

Yes

[@leblancmeneses3650]

How about using a 120 volt to 12 volt transformer with just an on off switch? That would give me a 60 cycle pulse out of the ignition coil but is there something I am not considering I dont want to give my dogs a permanent smile. Should I use some kind of resistor to limit the current? Thanks

[@shakerileiwat4341]

Good work

[@alfredkaserekasivanzire9488]

Some ppl were using CRT TV high voltage transformer for this.

[@donalfinn4205]

Well done.

[@edwardsooy3586]

nice and good job Ludic

[@ericomeli2235]

you forgot to explain how you limit the current to make it not lethal

[@Lsbud]

Where would I connect the output of a motion detector so that it only comes on when a deer touches it? I need to connect it to about 100 feet of wire.

[@invincible6623]

Good video 👍👍. Thank you

[@ludicscience]

👌

[@francomongillo]

It is not possible to read the first capacitor on the left in the diagram, what value does it have?

[@tracyforbes7317]

I would read through all the comments some have changed that cap ( the original is a 4700uf 16v) the big one on the left but like I mentioned there are a few possible changes to this circuit so you should read all comments they can be confusing but if you draw the circuit as is in the original diagram and then draw what you see in the video how it is on the bread board the comments will fill in the rest that seems to make since to me I think I've got a pretty good plan using original and then Airgunlab's comments and Mark Kay's comments adding to the breadboard pictured in the video. It's all I could do because the follow up on questions isn't getting to many replays since this circuit is pretty old. Good luck friend !

[@francomongillo]

@@tracyforbes7317 Heartfelt thanks in fact I have read almost all the comments, honestly I'm trying to build it and hopefully well, you are very kind of the answer thanks, in fact the wiring diagram lacks the connection of pin 4 of the NE555 to pin 8 otherwise in my opinion it doesn't work, I'm using a circuit simulator I hope I can get it to work. Thanks

[@concepcionjose72]

Can you connect this without the flashing light ?

[@maneshparmar9350]

There is a resistor on the board that is not in the schematic connected to the ground rail. The drawn schematic does not correspond to the prototyping board. What is the resistance value from A25 to the negative rail.

[@offgridmangogrower]

Excellent presentation Did you measure the current draw? Like to run this off a small solar panel…..

[@rodrigocorreia1653]

what is the name of the transistor and where can i buy it?

[@PonderFarms]

If another coil was added using the power from the first, would it increase the output? I use 7 joule chargers but they are A/C powered. I want to build something solar I can use away from the barn.

[@leblancmeneses3650]

How about using a 120 volt to 12 volt transformer with just an on off switch? That would give me a 60 cycle pulse out of the ignition coil but is there something I am not considering I dont want to give my dogs a permanent smile. Should I use some kind of resistor to limit the current?

[@keithyoung7381]

Great video. Thanks

[@edwinmkuzo3819]

This is what l wanted thaks

[@mrstratau6513]

Diabolical. Thank you.

[@danushkabandara7351]

4700uf 16v is a capacitor ,please check you schematic diagram .schematic hava 4700ohm 16v ,

[@electromagic3111]

Hi a have a question aboute the miniature voltage booster does it matters if the winding of the primary and secondary in the same side i mean from left to right both of them or it should be opposite. thanks anyway

[@douglasflores1462]

I think, given the few connections, it can be built without needing a printed circuit board nor the board in the video.

[@ludicscience]

Yes

[@TheArkcantos]

Just to say, based on the concept, I'm guessing even electric mosquito racket/bat also works right? Maybe at least for electric window grill.

[@MohammadShaneMohammad]

could you please provide the specification for the circuit

[@medusa569]

How did you connect the wire in that center terminal?? Did you touch it to the bottom screw and make it connect the sides and then epoxied or what??

[@ludicscience]

There is a screw at the botom

[@medusa569]

so you just wrapped it around the screw and then epoxied?@@ludicscience

[@ludicscience]

Yes

[@medusa569]

Thanks Ludic..finally i get the secret...onward with my emem.@@ludicscience

[@magicarpetmoto]

@@ludicscience when you reduced the capacitor to increase the pulse rate, what value capacitor did you use?

[@stanleys.karmoii7908]

in the case of rain, will the surrounding be energized?

[@ExtremeEngineering]

thanks

[@alfredkaserekasivanzire9488]

Mine has an alarm. When thieves touch the fence, it activates the alarm.

[@ronparker6489]

Very well done sir. Thankyou. I'm a retired B.S.E.E. and find no discrepancies with your diagrams. Perhaps I'm missing something?

[@douglascolman4501]

The first rung is the battery/power supply. Second rung shows 4700ohm 16v. ohms are resistance but the schematic shows it drawn as a capacitor. Please clarify this for me.

[@trench01]

you forgot to say that the poles that hold th fence should not be out of metal, and one has to touch the ground and the fence to get a shock which only applies to animals since they go not have shoes.

[@eaterofclams]

...of course the poles can be metal...the electric fence wire is attached to an insulator, not the poles. At least once a week you will find me replacing plastic insulators after a "deer strike". And the idea that only animals will get a shock if they touch the fence since they "go not have shoes" is absurd. While wearing boots is helpful in avoiding shocks, a 10-15 kV pulse will do it's best to find a way to ground; a task made sooo much easier if the grass/ground/boot leather/ feet are wet. [and sometimes the horses are wearing shoes. Metal ones. Doesn't protect them a bit.]

[@southernexposure123]

@trench - chuckle: I wear rubber boots and I touch my fence wire with the back of my finger to see if it's working. It shocks the tar out of me every time "unless" the fence wire shorts to the ground through grass or anything else that conducts the voltage to ground. When I get no shock OR a weak shock I walk around the fence and remove whatever is touching the fence wire and the ground at the same time. Oh, and if on some days I want a milder shock I pull a grass shaft and hold that in my hand to "test" the fence. When the fence charger is working I still get a shock (that won't make me jump back) while wearing boots. Touching the ground with my hand definitely gives a me shock, but touching the ground isn't required. You'e right about preventing the wire from touching the metal posts. I'm using T-posts driven a foot or more into the dirt but they have insulators to prevent them from shorting the fence wire to ground.

[@eduardoedit787]

does it kill a person once he or she hold it

[@user-ep1ih2sp2z]

Please give me this circuit diagram

[@michaelioannidis2885]

do you know how many meters of fence this circuit can drive? how do i estimate something like that?

[@tbfunk]

In my experience you can use 1 mile of fence for every 2,000v. So at roughly 20,000v you can probably safely use 10 miles of fencing with this.

[@evaldasvilkas2334]

not working just made it recently

[@sampatraophatak6440]

please can you make electric fence that works on 5V charger

[@ANTOperassic]

Impossible

[@sampatraophatak6440]

@@ANTOperassic ok thank u

[@ANTOperassic]

@@sampatraophatak6440 np

[@LakhsTsoyknikas]

like taser wow

[@moussaoussama8315]

Salam, yes, it is an excellent circuit, but I have a question, how to increase the voltage of a circuit, and how many volts?

[@bazrazin1]

i have 3in plasma ball and a ignition coil, made a similar circuit with 555 with pirmary in the collector of the transistor, i got mild hv shocks on the -ve of 12v battery. how to connect the common of hv to common of the circuit.

[@Taran72]

great video!

[@aloklakhera866]

What input ampere it withdraw for 12v input supply?

[@ertantum9315]

hi the circuit is working but my problem is that induction coil is getting too hot please help

[@pavletrubajic5269]

Maybe your duty cycle is too long check the diode that is beetwen the 1mega ohm resistor maybe its shorted

[@anesumadziyire6336]

Thank you. What parts am I looking for. Coil and capacitor. Any specs?

[@DanielPeaster]

What’s the little blue box wired between the positive and negative?

[@pavletrubajic5269]

Its the 33 micro farad capacitor

[@reaneya]

This is great, those cats that keep crapping on my land are gunna get it.

[@schitlipz]

Good idea. I wonder how I can implement it for pigeons.

[@reaneya]

'don't taze me bro' said the pidgeon.

[@kirkc9643]

I was thinking about feeding those pests using a metal bowl, a metal 'mat', one of those $3 'taser' modules from ebay, a motion sensor and a delay circuit (to allow time to commence eating :-P). Non lethal but they'd hopefully think about crapping elsewhere in future.

[@eduardoedit787]

gud idea ... my question once this will be hold by a person or animal this killed or not

[@kimo4646]

It doesn't kill. It has only 120 milliamps

[@BharatMohanty]

I am disappointed there should be live demonstration😁😁

[@ddbrothers5718]

I can't see properly name of mosfet and what is the voltage of 1uf capacitor

[@garsonprice3441]

Pretty sure it's 1RF244

[@cheded8535]

You didnot name all that you use. I dont know what are those other capacitors there

[@fpaulo20091]

hello I would like to buy this project. Can you provide a form of contact please?

[@ddbrothers5718]

where can i buy such a ignition coil ?and some connection are not understand easily in diagram so please sir explain dia gram easily thank you...

[@ewestpheling]

Any auto repair shop will probably give you one if you ask nicely. They connect to the spark plug in a motor.

[@electromagic3111]

You know you can use a relay anstad of ic and put the capacitor on the relay terminal to adjust the spark time

[@pavletrubajic5269]

Yes you can but you can not rely on mechanical parts that will probably brake after a long time of usage

[@waselectricsolution]

மின் வேலி அலாரம் சர்க்யூட் பற்றிய குறிப்பை எனக்குத் தர முடியுமா? நான் இலங்கையைச் சேர்ந்தவன் Can you give me a hint about the electric fence alarm circuit? I am from Sri Lanka

[@randomleinadz8883]

Sir can it run over 24hrs?

[@jimcatanzaro7808]

How about a 550v transformer at 250ma

[@Markfreeman920]

Is the mosfet a 244 or Z44?

[@hemanths2782]

Can I use this for big farms? Please help

[@leblancmeneses3650]

can I use a 120v to 12 volt transformer with a bridge rectifier for power source?

[@nohphd]

Yes, or a 12 V wall wart. Just don’t exceed 12 V and make sure the polarity is correct or your electrolytic capacitors may RUD...

[@smoke_stackz3168]

1.4hz at 2%duty cycle right?

[@schitlipz]

Does it work on people wearing rubber shoes?

[@kame8919]

hello, what transformer is the one in the video? I don't know English very well ... I would like to know the name of the electrical transformer.

[@JoshHopkinsYT]

Its called an automotive ignition coil. Here is a link to one that I just bought on ebay. > www.ebay.com/itm/BRAND-NEW-IGNITION-COIL-FOR-FORD-JEEP-LINCOLN-MERCURY-AMERICAN-MOTORS/224007691442?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649 Its just the old style of ignition coils for older cars

[@offshoreman71]

Can you make one that is 110 volt a/c?

[@psj3789]

How much current do you consume?

[@leblancmeneses3650]

what is the minimum amperage source I can use to power this circuit? can I use a 120v to 12v transformer? I am on my way to buy the parts hoping it will keep my dogs in my yard, we already paid $100. to get them out of dog pond once. Repaired fance $70. and one of them still getting out.

[@ludicscience]

Minimum 4 amps

[@leblancmeneses3650]

@@ludicscience thank you

[@Azam_Pakistan]

How much is the current?

[@among-us-99999]

Nice.

[@bobs12andahalf2]

Doesn't the mosfet need protection?

[@WTF_BBQ]

He ran out of condoms.

[@yz250ftony]

I would with a diode. flyback spikes. either across the parallel cap/coil or between the mosfet and coil

[@carterworo4467]

Now how about one with 4000 volt output and a spark that lasts no longer than .003 seconds and happens every second

[@TylerSmith-kt8rk]

Is the .33uf capacitor the capacitor that is between the two terminals of the ignition coil? 3:09

[@petqu_861]

Yes

[@user-rk1tg5mp7b]

Hi sir thanks for the video am a farmer in the Gambia ,am a farmer completely disturb by monkey at my bananas , I really want you to make one for me, my garden is 104m/300m ,please tell how much it cost including DHL thanks

[@mehmetdalfidan2354]

good idea but it is not working very well .firstly ignitial coil is using 2.7 amps at every cicyle so battery slow down ,secondly electrik shock isnt efective which is very poor ...thanks

[@LionBronstein]

12 volt car battery?

[@paulhillier9281]

Do you have a schematic?

[@128Wojtek]

Hey ! Your videos are pretty amazing ! Thanks ! Do You plan to do Q&A in the future ?

[@ddbrothers5718]

Can i more out put i mean 10 kv to 15 kv out put

[@whenufirstrealized]

Sadly, my calculations were off by a digit and now both my wife and neighbor are dead. My Lawyer is working on a plea deal.

[@shamstar2k]

hmm just remember not to get too close to the prison fence, as you might end up joining them!

[@pszeluga]

How many joules does this system have?

[@sujayghose3662]

The diagram is not clear..can anyone here help me assemble it?

[@oo0Spyder0oo]

It was very c[ear, what part didn't you get? They are all labelled.

[@ahmadbamarouf5954]

Great

[@electromagic3111]

Hi any one know why sometimes at the gate of z44 mosfat useing diffrent resistor like 100ohm -220ohm or 1k ohm ?? Any one can help please

[@James-yf6jt]

To control the turn ON/OFF time of the Mos ?

[@electromagic3111]

@@James-yf6jt does it depend on the resistor i mean 100ohm well be faster the on and off

[@James-yf6jt]

smaller the gate resistor, faster the switching.....but at the risk of damaging the Mosfet because of voltage overshoots during turn ON/OFF....

[@electromagic3111]

@@James-yf6jt overshoot ??!🤔

[@cheeryimmanuel5786]

Please how can I use the high voltage from the ignition coil to power my home appliance. Or how can the voltage be reduced to usable voltage to power my home Thnx

[@drumlightable]

This only produces very short duration high voltage pulses and the average power output will be far too low for your type of application. To produce AC power for your home from low voltage DC you should research inverters which are available with power outputs from about 50W up to many KW.

[@daveyjones5702]

so these ignition coils are kinda expensive, the ones for cars anyway. and i saw these small coils for motorcycles. do you happen to know how these compare to the car ones by any chance?

[@TheMaximzodal]

They will work OK. Not as high a voltage but enough to deter a varmit. Plus is small size.