Instructables
Picture of Monitor Hack - Security System!
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:

 
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Step 1: Materials

Picture of Materials
Materials2.png
Materials1.png
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.
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guysoft2 months ago

Metacafe is dead, and so is the video. Is there any other source to view it from?

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.
forwardbias5 years ago
Flybacks are actually fairly safe transformers for people new to HV. They output about 5-10mA. NST's can put out 30-60mA which can be lethal, MOT's put out AMPS, not milliamps but AMPS. Flybacks can cause a nasty shock and an RF burn at point of contact. But wont kill you unles you have a pace maker and hold the HV wire in one hand and the return in the other hand (Quite stupid even if you dont have a pace maker), or literally open yourself up and place the HV wire right on your heart. Just be carefull with what driver you use for the flyback. Some drivers like the XVS drive the current output of the flyback way up and into lethal amounts. The 2N2055 driver is fairly safe and simple to build. There is a 250,000 volt tesla coil available as a kit and you can direct arcs from a coin in your hand to the coil, and it dont shock you or pose any threat. As its microamps of current. And there are 150,000 - 600,000 volt static generators available in schools where they are encouraged to be touched, if HV is dangerous, why do they have Van De Graf generators in schools?

VOLTAGE DOES NOT KILL YOU, ITS THE CURRENT. Voltage= the number of electrons flowing in a wire, Current= the speed of those electrons.

Imagine standing in a creek with just a foot of water, eg a low voltage, now if that water is flowing very, very fast, just that foot of water can knock you down or run a car right off the road, (The current)

uA is fairly safe and can give a shocking experiance, once you get into mA however, above 30mA there is a risk of cardiac if you touch a wire with your hand, depending on how that current travels across your body and nerves ground, if your heart is along that path just 30mA can potentially be lethal. mA also tend to hurt, espescially at high frequencies where you can also get an RF burn. Once you get into Amps, espescially at 60HZ, grabbing a wire, the contractions in your hand make it impossible to let go and you will be electrocuted to death. Flybacks cycle at higher frequencies that tend to cause a violent repulsion from the device if you touch it, meaning you wont have a deathgrip on such a device. Why most injuries from flybacks are the injury from when a person flings their hand back in pain and slamming it into another object, falling off a stool or chair after getting a shock, etc.

Such injuries can be avoided by keeping your hands away from the thing when its energized if you are drawing arcs, etc. Use a long wooden rod to manipulate the wire attached to it, and HV can be a fun thing to play with. And

if removing a flyback from a TV, insure that any potential is discharged, which a CRT acts like a big capacitor and can hold a significant shock hazard long after its unplugged from mains. Use a resistor 1000 ohms clamped to a wire connected to ground and touch the resistor while gripped from an insulated tool to the CRT. A screwdriver connected to ground with an insulated handle will work as well, but will cause an instant arc, which can make UV light, damaging to eyes, and vaporise some of the metal in the screw driver which is not safe to breathe. Which caps tend to discharge very violently if shorted.

If you do get shocked from a flyback, you can learn from your mistake, (a very painfull one) and you will learn not to do what you did again (hopefully, unles you enjoy pain). Make a mistake playing with an MOT though, no second chances and you will be getting a ride in a hearse to a place 6 feet under.

I like this explanation! More then easy enough to understand.
Have you ever had the visual experience of about 1600watts running up one arm through your implanted neck plate "titanium" down the other arm and to ground?
I was messing around with a 1600 watt inverter last year cracking water "HHO"
and got a bit careless with excitement, That water instantly became foam, like opening a shook up hot can of beer in the middle of summer in Pheonix Arz!
So I was trying to bring it down a bit on the next try, had a bit to many beers myself and whollah! I saw a bright flash of white cover my eyes, will be a bit more careful now,, blew out the fett arrays and the microprocessor on that inverter, didn't kill me but did make me more cautious and curious,,,12 volt auto battery turned powerful?
You said that Voltage= the number of electrons flowing in a wire, Current= the speed of those electrons. Isnt it kind of reversed? I always knew that the amperage was the electrical "pressure" like the amount of water flowing in a river.
jj.inc kjbaran3 years ago
voltage is the pressure, current is the amount. So big amps = big pipe. High Voltage = little pipe w/lots of water.
I agree that the single transistor flyback is one of the best beginner voltage supplys but that analogy of yours is rather backwards current is like the amount of electrons and voltage is like the speed/pressure a decent airsoft gun shoots at upwards of 200mph, can give a nasty welt but getting hit by a car going 200mph is quite worse obviously i dont particularly like the saying current kills not voltage because voltage does matter since it determines the amount of current delivered When removing a flyback from a television its really not necessary to use a resistor usually i dont even hear anything and any spark generated would give of a very slight amount of UV and wouldent take a significant amount of material off of a metal screw driver, dont forget about the larger electrolyte capacitors on the tv's control board
Jawa8884 years ago
 Is this your cat
dead_cat.jpg
It's not mine, but you could probly get more traffic if you changed your sign too, "Free dog food!"
gaby1st Jawa8883 years ago
Yup,it is he touch the fence.
(removed by author or community request)
hg341 walshy1554 years ago
stfu he didnt do that and i didnt(nor would i ever) do
and i have 2 cats that i love very much(even thoug 1 piss's everywhere)
BUT i still think that is funny as hell
HA HA HA! That's funny.
its funny cos u can just reach over the fence and grab the wine and stuff, but cool instructable
bears03 years ago
i cant find the monitors ground?????
garet14 years ago
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?
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
ltnemo20003 years ago
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?
awesome awesome instructable.
thanks,
>G
Fireater9894 years ago
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?
Fireater9894 years ago
Your video isn't showing up. Neither is the video on your other instructable for the lightning globe: http://www.instructables.com/id/Maker-your-own-Lightning-Globe!/
I tried in 3 different browsers
agis684 years ago
well all was good done till when I show this poor pet circled with electric wire!!! You should shame!
knoxarama4 years ago
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?
pavalos5 years ago
My crt monitor goes to sleep mode every 5 seconds.. any recommendations so that is always on??
monitor settings?
This cant be monitor settings This is only a monitor  without setup buttons It must be signal detection circuit 
I think you can avoid this by bridging two pins on the VGA cable (not sure which ones though :P). I think googling for "VGA pinout" might help.
Thanks I will try it
CoolKoon4 years ago
I think you should put there a warning for anyone who's not familiar with HV that NO LIVING OBJECTS 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.).
legano4 years ago
n00b - coathanger wire?
lukas11215 years ago
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.
DANGER
For those who are a little new to electronics:
This may do you a lot of harm. To explain: Voltage is the size of the hammer, Current is how fast it is swung.
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.
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
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.
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.

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.

Good hack, but extremely ill advised for anyone who does not have experience in this field to try.

btw. I know that the sums used above are not entirely accurate but they illustrate the point of power.
A Big old tv will work right ??
*insert evil laugh here*
Yes it will
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