That old CRT monitor isn't as worthless as you might think!

Don't throw it away, hack it!

This instructable will show you how to turn that old dusty monitor into a personal electric fence!

WARNING: I shouldn't have to tell anyone working inside a monitor that there is a very real danger of being electrocuted if you touch the wrong thing. (You did unplug it first, right?)

SECOND WARNING: If you have a heart condition or a pace maker, you obviously should steer clear of this hack.

THIRD WARNING: The monitor I used for this hack was a small one. The voltage was quite high, but the current is not enough to harm you. It's enough to get your attention, but could potentially have the same effect as a very powerful stun gun.

Watch the video for the overview:

Step 1: Materials

For this hack, you will need:

- One used but working monitor.
(Size doesn't matter, regardless of what SHE says.)

- Some non-insulated wire.
Steel or aluminum will work.

- Some insulated ceramic posts.
Get these at the hardware store in the same section where the electric fences are.

- Some wire mesh.
Chicken wire works fine too.

Step 2: Discharge High Voltage

The anode of the flyback transformer could have some residual voltage on it, so you must discharge it to ground first!

Use an alligator clip attached from a long screwdriver to the ground strap on the monitor.

Carefully slide the screwdriver under the anode cup until you touch the center metal clip, or you hear a loud pop. If it's been a while since the monitor was on, there probably won't be any voltage left to discharge.

Once you've done that, it is now safe to remove the anode by squeezing the clip at the base.

WARNING: I shouldn't have to tell anyone working inside a monitor that there is a very real danger of being electrocuted if you touch the wrong thing. (You did unplug it first, right?)

SECOND WARNING: If you have a heart condition or a pace maker, you obviously should steer clear of this hack.

THIRD WARNING: The monitor I used for this hack was a small one. The voltage was quite high, but the current is not enough to harm you. It's enough to get your attention, but could potentially have the same effect as a very powerful stun gun.

Step 3: Wire It Up

Wrap a wire tightly around the exposed anode clip, and then tuck it under the CRT straps to keep it from moving.

Feed the wire through a hole in the case, and then put it back together.

Step 4: Run the Wire to the Fence

Run the wire through the ceramic insulators and connect it to the fence.

You can go a couple hundred feet, if the wire is properly insulated. A color monitor's flyback typically puts out around 30,000 volts, with very low current.

Make sure to put the fence on Styrofoam to insulate it from ground.

Step 5: Turn It on and Test It!

After double-checking your wire, turn on the monitor and test it out.

You'll hear a loud hiss as soon as you turn on the monitor. Use a grounded screwdriver to force it to arc to ground.

Even a small 15" monitor will throw a spark over an inch.

Step 6: Put Stuff in It for Safe Keeping

Now you can carefully put stuff inside the fence for safe keeping:

- Valuable jewels
- Your wallet
- The rest of your imported beer
- Your DVD collection
- Fine wine
- Your piggy bank
- Collectible Barbie
- Hundreds of other things!

(No Barbies, cats or pigs were harmed during the making of this video.)
<p>Metacafe is dead, and so is the video. Is there any other source to view it from?</p>
I have tested and it arks. My monitor has a built in feature that makes it arc to ground to stop it from damaging important stuff.
When I first tried this I heard a zttttttt. for about two seconds. It stopped for two seconds and kept doing that, like it was a cycle. Is that normal or a premature grounding. I have not tried to get an arc from it.
my home has 220v ac power supply. why would i use monitor? afterall u need ac current to turn that on. <br>
&nbsp;Is this your cat
It's not mine, but you could probly get more traffic if you changed your sign too, &quot;Free dog food!&quot;
Yup,it is he touch the fence.
HA&nbsp;HA&nbsp;HA! That's funny.
its funny cos u can just reach over the fence and grab the wine and stuff, but cool instructable
i cant find the monitors ground?????
when discharging, if I ground to monitor's ground, does monitor has to be plugged in? If not plugged in, then where the charge will go?<br />
For anyone reading this wondering the same thing, if you plug in the monitor and try to discharge it, the outlet will pump more electricity into it. Chances are you will melt the screwdriver in the process. Plugging the tv in defeats the whole purpose of discharging.
never find insulator cuz im unlucky
lol, your cat is in there. People do find them valuable.
Yo are gonna kill yourslef
so i did it and got awesome blue arcs but as soon as I tried welding, my monitor just started squealing and smelling like ozone. no mystical blue smoke. is there a fix?<br>awesome awesome instructable.<br>thanks,<br>&gt;G
Wait, so you have your large, clunky monitor sitting next to your fence (or lightning globe is what I'm trying to do) running a wire to it? I can't remove the flyback transformer and build a case or something for it?
Your video isn't showing up. Neither is the video on your other instructable for the lightning globe: https://www.instructables.com/id/Maker-your-own-Lightning-Globe!/<br>I tried in 3 different browsers
well all was good done till when I show this poor pet circled with electric wire!!! You should shame!
my flyback only gives an arc for about three seconds, goes off, and comes back on for another three seconds. is there a way to make it continuous?
My crt monitor goes to sleep mode every 5 seconds.. any recommendations so that is always on??
monitor settings?<br />
This cant be monitor settings This is only a monitor &nbsp;without setup buttons It must be signal detection circuit&nbsp;
I think you can avoid this by bridging two pins on the VGA&nbsp;cable (not sure which ones though :P). I think googling for &quot;VGA&nbsp;pinout&quot; might help.<br />
Thanks I will try it
I think you should put there a warning for anyone who's not familiar with HV&nbsp;that NO&nbsp;LIVING&nbsp;OBJECTS&nbsp;should be left in the cage while it's on (as I'm pretty sure you didn't turn the fence on while your kitty was in there :P). I'd also refrain from putting there anything metallic into it as they could short your fence to the ground immediately when you turn the fence on (i.e. soda cans, knives, especially watches etc.).
n00b - coathanger wire?<br />
ummm i used a huge old tv i discharged it took that thing off cnt remember what it whas clalled put my wire around one of the leggs and put it back in and then i put the other end of the wire to a cage i couldt find any chicken stuff so i used a regular mouse cage i used styro foam and i turn everything on "click" the power went i turned it on again and tried everything again turned it on and "click" the power went again i turned everything on again and turned the tv on... nothing happened please someone help me with my problem
um you could be doing a dead short somewhere maybe on the wires way out it hits something causing a short. to test and see if you fried it just hook it up to something and see if it still works if not well then tough luck and try again lol.<br />
<strong>DANGER</strong><br/>For those who are a little new to electronics:<br/>This may do you a lot of harm. To explain: Voltage is the size of the hammer, Current is how fast it is swung.<br/>This means that someone may hit you in the head with a normal hammer (small voltage) but if they swing really hard (big current) it will kill you. If someone swings a hammer the size of the empire state building (big voltage) it makes no difference how slow they swing (really small current) its still going to kill you.<br/>Colour tubes can have in excess of 30 000 Volts and the flyback transformer can be capable of delivering over 0.05A so thats a power of 1500 Watts Peak<br/>A 240V power point supplying 10A only gives you 2400W. So now consider what happens when you stick your fingers in a toaster then think about what the tv power supply could do to you.<br/>The other (and more important) danger is the frequency output of the flyback transformer, they very often go up into the RF frequency range. When you suffer an electric shock from these types of supplies it can give you an RF burn, what that means is that it can burn you not only at the entry and exit but the whole way down the path that the electricity took (read heart, lungs, and any other internal organ you like) this is obviously bad for your health.<br/><br/>Lastly even if that has not made you reconsider be aware of the live shasis found in televisions and if possible use an isolation transformer to protect yourself from electrocution.<br/><br/>Good hack, but extremely ill advised for anyone who does not have experience in this field to try.<br/><br/>btw. I know that the sums used above are not entirely accurate but they illustrate the point of power.<br/>
A Big old tv will work right ??
*insert evil laugh here*<br />
Yes it will
30,000 volts may or may not be harmful with low amperage.....another factor in AC current is frequency. I have had 200,000 volts ac at a VHF course through me for about 5 - 6 seconds.....and it hurt like hang (Some HV stun guns are in the 100,000 volt range), and I have had 80,000 volts pounded through me from an ignition coil while someone was starting the car......and although that didn't kill me, if felt like I was being HAMMERED (my chest was leaning against the bumper of the VW at the time), hard, in the chest and hand/arm. Great caution is advised, but there is no need to instill unwarranted fear either.
i just used a grounded wire at the end of my 'safety stick'.
your mom grounded my saftey stick. jk. I just bought a 100kv power supply off of ebay for like $60 yesterday. I plan on doing some lifter experiments.
I'm 1 year away from becoming an engineer, an one thing I know for sure, and that is , that kids, should NOT be playing with flybacks, 20,000 volts, are not a joke, an seriously if you don't know what are you doing, don't do it.
Wouldn't this be better if, instead of just a fence, you used a mesh dome that opened up?
What is the current for your CRT monitor? And How would I be able to determine the current and voltage for the one I own.
whan you take the thing of and put the wire on it do you put it back before you close the case or do you just leave it hanging
leave it hanging
Awesome! Now I can keep that pesky old Possum out of my trash cans! Hmm..... How's it do in the rain?
J,ergs,Kcal,cal,BTU's,Ft*lbf,Therms,Mev,ev. all measure energy, the same thing
My apologies, it was Kipkay, not NK5 that was on the Science channel.
I know it's a little late now but... I deleted my rant on the 'helmets and seatbelts' discussion, and I thank everyone for telling me to do so. This was a great Instructable, and my comments had nothing to do with it, and I won't rant on totally irrelevant subjects anymore. Thanks for the necessary criticism, and great Instructable! PS: I know I'm sounding like a total idiot, but NK5 was on the Science Channel!! PPS: Yes, I know NK5 was probably on the science channel before Instructables, but it's still awesome to have a member on TV!
Incredible, I couldn't ever believe that that was possible =P<br/>
i once had a camera taser hooked to my metal doorknob, worked great keeping the siblings out. this might have a little more zap though...
Just a reminder as most people failed to mention in the comments that mA are enough to kill if given the right conditions, the resistance of human skin varies person to person and body part to body part, wet skin conducts very easily, dry skin can too if enough electrolyte is present like salts or something, anyways---- if your not careful you could potentially kill yourself even if the amps are relatively low, though the chances are very unlikely-- someone has done it before or no one would be afraid of it happening-- Flyback transformers are capable of generating lower voltages and higher amps depending on which inner coil is used and also a wire can be coiled on the iron core to produce even higher voltages above 60Kv, as with most things involving HV - be smart while being stupid :)&lt;br/&gt;<br/>
please nobody put a cat in your fence

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More by NK5:Confetti Bomb Prank! Make a cool hologram illusion! Make your own Lightning Globe! 
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