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- เผยแพร่เมื่อ 28 ก.ย. 2024
- Random Bunker dumpster item teardown. A 20 year old Australian designed and made electric fence controller.
Repair guides are here: pakton.com.au/...
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#Teardown
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UPDATE: Pakton have responded and unfortunately don't want to release the schematic for the MBT200. They are actually a bit embarrassed by this old unit and think "the plastic case was horrible".
They have offered a more modern JVA brand unit for a loan teardown and are happy to answer questions on operation etc.
The designer (Paul) has chimed in with a few comments:
"That unit was one of the first prototypes of that model, hence the "not for sale" on the back. I designed that unit. The PCB and firmware were all Pakton.
JVA is our in house brand. Pakton is an OEM designer and manufacturer, we make and badge product for a lot of the other brands in the industry. 90% of what we make is exported, we are one of the larger manufacturers in this niche in the world.
It was a very reliable model. The output transformer is our most reliable by far. It was designed by myself in conjunction with an incredibly talented engineer in NZ called Bob Smith of Marque Magnetics, since deceased.
One of the key new features in this energiser design (when it was released) was the moving of the filter capacitor (usually across the primary) to the output. I had a patent on that. This improved the pulse shape without increasing I^2R losses in the primary, it also allows the leakage inductance of the transformer to work with the filter capacitor (or more accurately it's reflection in the primary). The goal was to produce a soliton pulse shape when coupled to a real fence. We did a lot of testing on long fences in western Queensland. Real long fences are mostly capacitive in load. I.e. lots of reactive power flows. We have since patented methods of measuring the real versus reactive so we can isolate faults. Some of our monitors can pin point a fence fault to within 1/1000 on the fence. See the ZM20.
The move in electric fencing now is all towards monitoring, farmers do not have time to test their fences, and it's critically important to know if there is a fault on an electric fence if it is being relied on to keep stock in or bad guys out."
Ah that's too bad, but to be fair I can relate... hehehe
Very decent of them, it'd be great to see a teardown of a modern unit.
Meh id rather see the old unit fixed! Altho both could be nice.
looks like ya gonna have to do it the hard way Dave! :P
...and do a side by side - old vs new!
2 birds...one stick! LOL
I worked on a solar cellular electric fence detector. It would verify the fence is working and phone home when it had an issue. It would also give periodic updates.
I love Aussie caps!!
Its just: in the northern hemisphere you have to mount em upside down so no electrons gonna fall out!
I never see those caps at the parts store, They must keep em Outback!
Clever!
I was holding onto a fence surrounding a horse field, I remember looking at the farmer hooking up the fence to close it behind him. It only took a little moment before I got zapped. Learned a valuable lesson that day.
Dave! Do you really have to ask whether or not we want a reverse engineering video?! How long have you known us?!
Good point
I think most of us want one. I sure do!
I was thinking it would make a fun diagnostic video as everything looks in good condition it makes for a deceptively unfixable product. I have a few of them in my repair graveyard.
In the 80s I remember my grandad used to test his electric fences by touching them with a blade of grass held in his fingers. It still zapped you, but much less than touching the actual fence.
My dad touched an electric deer fence in the alps once with an aluminium walking pole. He said there was a large *crack* and then the pole shot out of his hand. Apparently he was pushing the fence down, ready to climb over it 🤦🏻♂️
James Grimwood yep, used to do the same.
I touched an electric cow fence before. Doesn't feel like a shock at all, feels like someone kicking you in the arm and chest.
Depends how you touched it
I got kicked in Oklahoma years and years ago with a bull fence.. I was 12 or 13 and pulled the Jurassic park and grabbed it to pretend I was being shocked to my cousin and it kicked me so hard I woke up on the ground smelling bacon.. burned my forearms and had a REAL barbed wire tattoo for almost a year..
Depend of how well it’s installed and how much grass is grounding the fence. Most of the time I touched them, they hurt but not that much. You need to think that cows are way better grounded then us so maybe it hurts them more.
I also got shocked by some wire fence, it wasn't that bad. (Don't know how exactly those work, but they normally didn't shocked you by just touching, you had to touch also some ground). Definitively a lot less than a 220V AC shock, which I've also got multiple times. (Yeah, I'm kinda clumsy :) )
Guessing this is because it's DC, so the muscles only tense, they don't tense/contract as they do with AC
Hi Dave, I love these random teardowns! Keep up the good work
They used to place the schematic inside the case.
Electric fence worst enemy, "LIGHTNING"
Hey Dave, bush electronics repairer here....the yellow lug is sense, its designed to go straight to a peg in the ground, or directly connected to the green lug to give feedback when it dumps its joules.....also 3KV is a small unit, I have measured a 200KM unit at over 12kV, approx 2KM out.
The official bush test is holding a piece of green grass and holding it against the hot wire on the fence, if you can feel the zap then you are good. Gallagher had a unit on display at Ag-Quip a few years ago designed for 200KM+ runs and it was basically burning the grass with a 2M piece of 2.5mm fencing wire.
Edit: When they break it is usually the caps or transformer that goes, 50% of the time it is from corrosion, often just on the spade terminals you were praising, I have seen it a few times where farmers will keep the energizer in the same shed as bags of ferts/chemicals....ants are a good one too.
I've had a couple of little consumer units, rated for less than 5 miles I think. Having seen what was in those (next to nothing), I didn't expect much in this one, so I was quite surprised at how much more sophisticated this one was.
I used to spend summers on my uncle's farm when I was a teen in the USA back in the 1970s. Farmers around where he lived all had electric fencers similar to this to keep cows from getting out. Although they were much simpler design. They would output a pulse about around 20KV in about 2 second intervals. Yes! You knew when you got a jolt from that.
Beautifully made unit!
14:03 I Calibrate 10Kv HeNe Laser power supplies for a living, and yes, I have been bitten from left hand to right hand. Painful is an understatement.
I bet!
Garrett, No, Really?
Yes really. But I must make it clear how awesome my job is. I mess with lasers and HV all day long. And I get paid to do it.
@@garretthaynes8814, I was just being facetious. When I was young (about 11 or 12) I accidentally grabbed hold of the wrong end of a 25,000 volt transformer. That thing knocked me across the room and got my full attention. I vowed to NEVER do that again! Later in my life, while working on a car with an electronic ignition, I discovered what it's like to grab hold of about 65,000 volts. Again I became more careful around those things. In 1993 I was asked by a friend to find out why a 440v 3 phase motor had quit working, checked it out and found 1 of the slow blow fuses had failed. Turned the breaker off, then reached in to pull the fuse out. That's when I discovered that the IDIOT who wired it ran the main power through the fuse first then through the breaker then to the motor. When I look back on my life it's a wonder I'm still alive! I think having a job such as yours would be interesting as all get out. Just remember that the pain will most likely abate after a while...... maybe!
Geez, I thought I had bad luck lol. But you do learn quickly to discharge those caps before grabbing that unit lololol
Get it up and running Dave, then send it to Electro Boom to play with! lol
Helpful rewiew video 👍
Energy is high to burn off blades of growing grass. ONLY GROWING. After off period necessary to inspect length of fence to be clear of over growth or could ignite fires. Similarly fence must be clear of major bushes and branches blown by wind. Growing plants burn away the tips before being a problem. Many fences units drive hundreds of km length of electrified line.
Interesting is how few city folk recognise a electric fence and get zapped. Many years ago I was retrieving a RC glider from a paddock opposite the flying area. On return a father and son were also retrieving one. The son ran ahead leaving dad with a wire between his legs. I asked "if he planned more children" which got a puzzled look. I pointed at the insulator on a pole a few meters along the wire. Still no reaction. I pointed out he was straddling an electric fence and could be educated in unpleasant way. He jump off instantly, but no thanks offered.
This video made me damn proud to be Australian... wait, Im American, but still somehow Australian pride consumes me.
Me too and i live in bloody Lancashire mate.
I'm from India, so yeah.
Yikes, they gave me 200 joules when they cardioverted me out of a-fib, guess I’m glad they knocked me out!
I had a mate who was defibbed while he was still conscious. Apparently the level of "discomfort" was "intense" :-)
Very glad. Think a horse kick to the chest.
@@xjet Damn, must be bloody painfull!
Same for me. I've been cardioverted 6 times, and by the nice red marks left afterwords I'm glad I was out for it each time.
Tony Tanner you’ve got me beat, only twice for me so far. First one I think I was 34?
Do follow up video about fixing it, you can then set up electric fence as a prank for other people in the corporate office building
Imagine having worked at Marconi and not being dead. Nice work mate.
I always liked the ticking sound that the fence controller made on our farm when I grew up.
Touching it was less pleasant.
Would that have been the bouncing lever style from years ago?
@@jostouw4366 I don't really remember what type it was, it was around 20 years ago and it was sold in the Netherlands
When that fence controller was made, I still was friends with an old lady from the neighbourhood here in Germany. She owned the house she lived in and rented out the ground level flat to brush up her not so great pension.
It was only a question of time for her to hit a rock in shape of a single man in his fifties as renter who needed a hut when his wife kicked him out. He started to booze and turned into the mother of all f***ers, an agressive, mindless monster and had to leave not too long after. When he found a new place a couple of hundred meters away, he started a daily routine of taking a walk late at night, stopping by at his old landlord's house and pishing on the door. It only took a short while for the entire hallway to smell like a badly maintained public toilet…
My girlfriend owned a horse. So she owned an electric fence unit. She didn't need it at the time and kindly borrowed it to the old lady. It took some tweaking, but I managed to find a spot where a discretely invisible piece of wire could peek out into the area usually hit by the boozer's best efforts.
It worked. ^^)
I touched electric fences before but I doubt they had as much power as that device can put out.
Little fences to keep in sheep don't hurt too much.
I've reached over an electric horse fence that was armpit-high and as soon as my armpits touched it, my arms came down over the other side of the fence and if my legs didn't give out, I'd probably have gotten a good frying. These things are fuckin powerful.
I work with fence chargers for a living. While I've never used this specific one, I can make a few guesses based on what I know
First off, the ground line is meant to be connected to literal earth ground and the other two to fence isolated from the ground. It should work with or without anything connected to it
Secondly, these are usually designed to send out pulses every 1 or 1/2 second, and the current rating stamped on them is usually the average over time, so when you consider it's not drawing current most of the time, the actual peak amps is usually much higher than the label. I've seen them blow five amp fuses
Third, most of the time when they say 12vdc they mean a 12v lead acid battery, which, as I'm sure you know, is actually a little higher than 12v. Most of the ones I've used have a built-in battery protection that cuts out or switch to slow pulse at 11.5, and I wouldn't be at all surprised if some of them actually cut off at 12. You should try giving it 12.5 or even 13 volts if you haven't already
Lastly, if you're poking around in one of these, keep in mind that they're designed to deliver a painful shock through several miles of fence and earth, to animals with thick hides and hooves. It hurts a LOT more when you touch the wrong thing inside with a screwdriver. I have heard stories of them causing heart attacks
I forget sometimes to discharge capacitors on small electronic devices this thing seems like there is no coming back from making the same mistake
Yeah I just zapped myself like a few hours ago.
I still have one of these in service, the ground goes directly into the ground, like a large copper rod driven into the ground, the other 2 terminals are your loop
Not one of the real oldies, built before circuit boards. They used to have one condenser, a coil and some breaker points on a balance wheel. These were a later development on the original fence charger, which was a trembler coil box out of a Model T Ford.
8:46 That "discreet opto-isolator" arrangement is not uncommon in applications like electric guitar effects pedals. In fact, the Dick Smith tremolo effects box used it.
I know a guy who melted his nice gold watch when his car was getting worked on and he was saying stuff like what's taking so long and goes over to the guys working on the car and reaches in to do whatever and grounded a positive battery cable and car frame-thing turned into a solid band of gold and burnt his wrist horribly
Is this what you guys use to keep the Drop Bears out down in 'Stralia?
Thank you Dave :)
Reverse engineer the thing... And Was that big resistor you used at the end as a load, you said was adjustable! originally off a type of rheostat setup???
Lets make it work! YES!!! Reverse the crap out of it!! I love this stuff!! Give it hell mate!
I can't wait to see more of this.
I've repaired various models for farmers and believe me yours is a "Rolls Royce" in comparison. Great for running wire under a seat cushion and watching folk go into orbit. It doesn't kill em just lights them up a bit.
Please do a follow up on this. I think u r a genius!
I'm surprised they provide a centre tap. The fences I've used only had two terminals: One to be connected to an earth stake (or a length of traditional stock fence etc. The other, to the electric fence. So, I guess the green is for the earth, and the yellow and red are to provide two different power levels.
The shock shouldn't be too bad . If Dave fixes it and has a healthy heart, I think he should try getting zapped for us.
They provide a center tap so you can run two wires (positive and negative) down the fence. This helps to reduce electromagnetic interference from the high voltage pulse travelling down the fence, it also helps to ensure even in dry weather you have an excellent return path (i.e. a cow pushing through the fence will come into contact with both the positive and negative wire and experience the full voltage).
Thanks Philip S. I guess sheep would get the most 'benefit' from the double voltage, seeing as they're so well insulated. I didn't think about the dry Australian weather, though. I guess they have more centre tapped fencers in Australia than they do in humid France or UK.
I had access to a NZ built energiser, just for a joke I hooked up a jumbo LED directly to it's output
The result was a guaranteed, on the first pulse, decapitation of the LED, it would blow the head clean off with quite a bang - it was quite brutal, afterwards the ruminants of the LED sometimes caught fire.
I had a great time trying to capture the moment with a high speed camera, with a little success,
Pity I don't know where those pictures ended up.
2.400v sound low, around here 8.000-12.000v is normal.
@@georgechiporikov2297 Add voltage drop from resistance of kilometers of wire and voltage drop from every blade of overgrown grass that is touching the wire. I have 7kV open circuit 7J unit and at 2kV its not reliable anymore, some cows will just power through.
1:18 - you have all 12 caps in series -- not just the 6 that are grouped together at the one side.
Fascinating. Also intrigued by the fact that there are actual lethal power electric fences. I thought that was a myth. Honestly if a solid 1200-1500V pulse won't sit you on your butt I don't know what will.
Many fences can have more than 10,000 volts of potential, but they may not have much power.
@@user2C47 Sure, shuffling your feet on carpet and touching a doorknob can give you a 20kV zap. It's Amps that do the business. That string of caps on the output of the zapper above would be able to back it up with some amperage. I find it hard to imagine the benefit of applying more power than enough to dissuade someone from touching it.
11:00 All 12 caps are in series, so double the voltage!
Some severe magnetics voodoo going on in that thing, "...improved pulse shape without increasing I^R losses in the primary, it also allows the leakage inductance of the transformer to work with the filter capacitor (or more accurately it's reflection in the primary). The goal was to produce a soliton pulse shape."
Few electrical engineers can get this stuff right in any normal design window. They do it on personal machismo. I mean, Dave Jones work on low burden front ends for voltmeters is not shabby, but...
Aussie made and manufactured. There's history for you!
Nice Teapo SH Caps right next to the Big Aussie ones :D :D
Could anyone tell me if this guy did a multi meter protection video, movs, spark gaps etc, thanks,
I want to see a reverse engineering of anything you want. Literally anything. I want to watch
Yes. Follow up plz.
I almost hope they dont send you anything so we have to reverse engineer it :P
I'm keen for a reverse engineered video.. and perhaps the comparison against the new one once it arrives
16v AC or 12v DC? Was this mixed up? Doesn't it kind of like make sense to have 16v DC (super highly charged lead acid) or 12v dc. Where 16 = sqrt2 * 12?
I worked on these units. It shouldn't care which source it is running from. The 16 V a.c. input is for mains connection, the 12 V d.c. input is for a battery backup to keep the unit running even if power fails. From memory it trickle charges the battery through a large value resistor, and then uses a diode to switch the battery into the circuit when mains power is lost.
So they've connected multiple caps in series to increase their voltage rating? This is not how ya doing. If ESR varies, caps may be exposed to higher voltage while charging.
Plessey... now there's a name i have not herd in a very long time
That's kinda shocking!
Whaaaa?! No it isn't! The only shocking thing is how it isn't shocking!
hope ya tested it first ;)
I once had some goo Muck boots on and had accidentally rubbed the fence and go no shock so I did the flick test and then grabbed it and it did not shock me. My boys were there and I told them it was dead and then they felt it !!!!!! IT WASN"T!!!
Straya Caps. Shit yeah!
Would love to see a reverse engineering of this thing, but as you mentioned earlier the new loaner teardown would be just as interesting. Those things hurt as hell, speaking from first hand experience. Non-lethal to healthy individuals tho'
What about a teardown and review of the Keysight PA2203A Power analyzer?
That might be interesting.
Yea all the old factory buildings around here are apartments, condos, shopping centers, or just gone! We don't make much around here! Just sell it!
The city I live in used to be a huge factory that made canned goods. In the 1950s, important farmland flooded with saltwater and all of the oysters had been removed from the bay, causing the company to go bankrupt.
Now only one abandoned building remains.
Plessy Navel Systems ?
I don't think so !
Plessey Naval Systems I presume
They make belly button products and accessories.
My first job, back in 1979, was in the EW labs at Plessey Avionics in Ilford, UK. I left there in 1981 to work at GEC-Marconi in Borehamwood, UK. Avionics shut down in 1989 and the site was sold off for housing and a shopping centre. Small world though!
LOL, did I type that?
@@EEVblog Someone has been gathering some fluff recently
@@EEVblog Have to admit I did have to rewind and listen again a couple of times to be sure I'd heard you right, talk about déjà vu! I designed ground-to-air and command & control radio systems and later got involved in synthetic aperture radar and did a little bit on ordnance guidance systems before moving on into commercial computing, early mobile phones and a few years on space craft instrumentation systems.
Only recently discovered your channel on TH-cam (and now lbry too) but really enjoying following your exploits - and the nostalgia!
Hated them as a kid. My neighbor had cows... zap!
0:00 careful you might get a shocking experience #dadjokeoftheday :D
A section of a downed 12kV power line from several years ago: randomer.net/stuff/downed-line-sm.jpg
Don’t whiz on the electric fence!
Fail
5:03 Anybody else notice that little tiny stray copper wire chilling there on the PCB near the center of the open area?
That may be a bit of the plastic casing.
Edit: I'm fairly sure now. 5:36 it's on the opto tubing too
No.
Yes for reverse engineer!
Eh, at that voltage you can measure it with your toung! Let us know!
11:19 iPhones start losing their tihs...
Would be great to see you reverse engineer it. Even better, reverse eng it while it's powered.
Reverse engineer would be nice
APPROVAL NO : Q????
Do not pee against a electric fence! You will never forget it! But i want a explanation how this Units are woking since my friend peed fucking drunk against this electic cow fence. Dont ask, reverse it!
Would love to see a reverse engineering of this thing.
Me too
Bigclive would have seen for himself if the output worked, he's his own volt meter!
More like ElectroBOOM ;)
The calibrated finger has 3 levels:
1 - Yep it's on
2 - Ouch
3 - Bloody hell!
@@EEVblog that precious moment where you're not sure if you've had a fright or you're in fibrillation
@@mixerfistit5522 Oof lol, tell me about it. "Am I holding my breath, or am I physically unable to breathe?"
Never a good question to ask yourself lmao! Great vid btw EEV. Be safe guys and gals.
@@EEVblog It also has an overload protection feature, but can only be used 8 times.
When I was much younger, my buddy and I decided it would be a clever thing to run an insulated wire from the electric fence surrounding the pigsty over to the nearby metal clothesline as a "surprise" for my buddy's mom. We ran the hidden wire and the last step was to reach through the barb wire fence and hook a little loop onto the electric fence. I squatted down with my derriere a short distance from the ground. The moment the hook connected with the electric fence, there was a discharge between my butt region and the ground. I learned everything I needed to know about electric fences in a few milliseconds. I basically defibrillated my privates. I have always been careful around capacitors and anode terminals on CRTs ever since. Yowzer.
The reason it happened is because the insulated wire you used wasn't rated for that kind of voltage. Your average run of the mill agriculture shock fence will put out 10-15 kV at a very low amperage. As you learn in welding, the voltage is what strikes the arc, the amperage is what burns. The amperage isn't enough to kill you, but the voltage is more than high enough to penetrate clothing and fur, without penetrating the skin. So getting zapped by either is basically the same thing, really. There's about 1kV per diagonal inch of CRT, so your average CRT computer monitor would be between 10-20 kV if it still held a charge.
@@BlackEpyon Cool info on the CRT telly's there.. : D my dad pissed by mistake on an electric fence when he was a young fella.. he said it went up through him from the tip of his Lad to the tip's of his Toe's & left him ten feet back on the ground holding his bit's in pain.... its a fuckin wonder i was ever conceived at all : P Not something id like to experience myself!!!
Thanks, I almost fell off my chair, pissing myself laughing. I had to keep stopping becuase I knew the next bit or the story was not going to end well.
@@keithking1985 LOL!
I've never been "bitten" by the fence like that, but I've zapped myself on it a few times. Spooks you silly each time, but with these residential/agricultural grade fences, the point is to scare you away from the fence, not kill you.
Zapped myself at least once on a CRT as well. You see, when I was a kid, my dad taught me to take apart CRTs and tune them (focus/color, etc). This has to be done live so you can see what you're doing, so the bit he didn't teach me then was how to safely discharge them, and that glass tube acts like a giant capacitor., aside from the DC filtering caps.
With these CRTs, the goal is to get electrons to flow from one end of the tubr to the other, so the voltage is very high, but the current is low, both to avoid burning the tube, and so that you don't draw an absurd amount of current at the wall outlet.
@@BlackEpyon i learned how CRT's worked from watching videos like Dave's ETC,, im teaching myself electronics & loving it... i have a few fly-back's in my parts box from old telly's!! i always keep them when i come across an old TV.. think of making cattle prods outa them.. Irish gypsy's would love to get their hands on them too. & seeing that im 1/4 traveler im in a good position to not get ripped off selling the odd one hear and there.. YA get me!! but yeah!! i always look where im pissing when im out shooting/hunting/fishing... ya just never know where a surprise might be hiding!!!
*tries to imagine dave getting zapped by it*
Send it to electroboom 🤣.
was just wondering if it required on its "first startup" that it required that 16v AC to start the transistors or something along those lines , then 12v DC was "backup"
I did try the AC input but it did the exact same thing.
I worked on these units. It shouldn't care which source it is running from. The 16 V a.c. input is for mains connection, the 12 V d.c. input is for a battery backup to keep the unit running even if power fails. From memory it trickle charges the battery through a large value resistor, and then uses a diode to switch the battery into the circuit when mains power is lost.
Pleas, please, please send it to ElectroBOOM! Please!
That'd be some fine content.
Having been nailed with a similarly sized one here in the US of A, I can assure you it hurts like a son of a bastard and you'll certainly know about it.
"Ducon" is such a refined french word for ... A**hole
@Mai Mariarti : full disclosure, "con" in French has the same literal meaning as the c* word in English, although it's considered a rather mild insult unlike its English sibling. To refer to the other ... orifice, we'd say "Trouduc" (which is about on the same level of rather mild to average insult).
I'm french speaking and I laugh every time I find a ducon capacitor
@@ordinosaurs that meaning of "con" is pretty much not in use anymore. The contemporary meaning is closer to d**khead.
@@randomelectronicsanddispla1765 : yes, that's why I said "literal meaning". And although I agree "un con" is roughly equivalent to "dickhead" in potency, I think "ducon" would be better translated by "plonker".
Maybe contraction of "Dubilier Condenser".
www.gracesguide.co.uk/Dubilier_Condenser_Co_(1925)
www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=13698
When I was younger ;) we would test the fence charger by grabbing a long reed or length of grass (meter and a half or so) and then slowly walking it over and in contact with the fence wire until we just started to feel the tingle. From this we could gauge the charge in the 12V batteries used to power the devices.
Yes, that is how I used to check them when hunting in rural US. We'd use a blade of green grass and cautiously move it on the wire.
Yeah when I was a boy we made up contests of who will get closest to the wire using a blade of grass.
And my dad's trick was to grab the fence with one hand and one of us kids with the other and conduct the shock to us. He was wearing rubber gum boots.
@@dougvb9048 That was either really weak fence or your dad is a tough guy :-) I have 7J 7kV unit and that will go through wellies like nothing even if its down to 2kV because of distance or overgrown grass shorting it out.
Just type "who invented the electric fence" into Google and the truth will be revealed. Damned Aussies hitch-hiking on the shoulders of giants :-)
I can just imagine how many Google searches are going to happen because of this statement. That would be interesting to know.
I figured it had to be the Kiwis after a comment like this!
Bloody awsum
When I was a kid, I distinctly remember peeing on an electric fence when I was at a demolition site - they were demolishing old power station cooling towers here in the UK. Thank God the fence wasn't on at the time. Looking at those caps, I think I'd have had quite a shock! Pardon the pun!
You probably wouldn't have gotten a shock, pee breaks up into separate droplets after leaving the exit tube.
@@Mariano.Bernacki not when u are a guzzler and shorter like me. The first thing it hits is the fence wire
@@Mariano.Bernacki yes its seperates, but this is pulsed high voltage on these fences. Believe me, my friend has a bad expirence with that.
The beam hits the fence before its seperation. And high Voltage can jump from the salty pee drop to another! Then pee is a good conductor. :-)
@@Mariano.Bernacki
I actually climbed up the fence afterwards, so it was definitely off. :)
@@Mariano.Bernacki, I learned a valuable lesson when I was 5 years old. My parents told me not to touch the fence, so I didn't, BUT one afternoon the neighbor's dog came over and took a wiz on the fence. Judging from the response from the dog, I think that he would DEFINITELY DISAGREE with your statement! Oh, buy the way, I decided to follow the advice of my parents!
So the way these generally work is on magnetic impulse. The caps charge at and store a lower voltage charge on the order of a few hundred volts. Then at regular intervals a triac triggers and dumps this into the transformer, which has a HV secondary to the output terminals, boosting the voltage to the kilovolt output.
The ticking noise these boxes make is not a relay, it's the magnetostriction of the transformer core getting all that current dumped into it from the caps.
I repaired one myself previously with a failed triac (same symptoms, not ticking when switched on). It actually had a spade-mounted capacitor inside that could be changed to alter the amount of kick it gave (depending on your type of livestock, I assume)
Tesla strikes again!
Growing up in a rural area in the 1980s, I have grabbed more than my share of electric fence. Pretty unpleasant.
12 Joules? That thing must have a serious bite if it gets you.
Airsoft guns be 1 J... I think it definitely zaps a bunch
Cows need a lot of persuasion.
@@chasmosaurus3 particularly when the ground is dry, at the model aircraft field I fly at, I caught a momma cow and baby cow on the airfield, as I got out of the car to film, momma cow just very calmly lifts the fence up and walks under it :O so we now have a ground wire lower down and they haven't tried it since :)
its gotta FIX IT FIX IT FIX IT FIX IT FIX IT (tho i think pebkak
Dairy Farmer here; livestock fence units are normally either 5kV (sheep/small lifestyle blocks) or 10kV (Cattle/large farms). Although voltage can increase as you move down the fence line, due to bounce effect, or decrease due to shorts.
I once "calibrated" one of those with my nose. It worked, but my nose didn't for the next 30 min.
Hi Dave, I know how you like back to the future and the delorean so I saw a metal model kit of one and thought you and sagan might like to build it. So
if you google: metal earth delorean you can at least take a look at it. Thanks for all you do and stay safe down there...
Enjoy your walkabout @EEVblog .. Turn them electronics off and take em apart. We will see what happens with the stationary cattle prod when you come back
"Anything over 12V scares the shit out of me" - ElectroBOOM wants to have a word with you!
Is this for keeping 'roos off ya property? :)
Please reverse engineer it!
When I was young like 8 years old getting into electronics I found an old school fence charger at a flea market! I figured it ran on 120v AC being a dumb kid turns out they mostly ran on 6 or 12v and it was very a very simple pulsed circuit with a coil and coil spring. Anyway short story I hooked it up to a battery charger and “LEARNED” electronics in one zap! Some would call this dangerous now days but you know I could prob still draw out that circuit and describe how it worked to this day! After it knocked me on my butt I had to know how I the word could 12v DC which I couldn’t even feel get transformed into a pulse that knocked me on my butt!
Mum worked in Plessey Belfield doing relay contacts for telephone exchanges, before moving to Meadowbank where they switched to electronics.
All the guys are daring themselves to grab it.
I grew up kind of poor and as a mechanic I cant help but repair anything like this I find, Resurrecting things is always satisfying .