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Picture of MAKE A HIGH VOLTAGE SUPPLY IN 5 MINUTES
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In this Instructable you will learn how to make a High Voltage High Frequency power supply in 5 minutes and for less than $20.

All you need is a compact fluorescent light (CFL) and a flyback transformer.

Flyback transformers are found in TVs and CRT monitors. They make the high voltage, high frequency current necessary to trace the electron beam across the screen. They are small and compact, and you can take them out from an old computer monitor or TV.

CFLs are very popular high efficiency fluorescent lights. They are similar to their ancestor the fluorescent light tubes but use electronic ballasts instead of the big and heavy ballasts in the old technology.

The electronic ballast works by generating high frequency currents that are fed to a tiny high frequency transformer that boost the voltage and run the fluorescent tube. It is the high frequency that makes the assembly compact.

The electronic ballast generates less than 1000 volts. But by replacing the fluorescent bulb of the CFL with a flyback transformer, spectacular voltages can be achieved.


Please visit my latest instructable, how to build an 2.4Ghz yagi antenna for long range WiFi or surveillance cameras:
http://www.instructables.com/id/Easy-to-Build-WIFI-24GHz-Yagi-Antenna/
 
 


 
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Step 1: Some Info on CFLs

Picture of Some Info on CFLs
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CFLs can come in a variety of shapes and sizes. Generally the bigger the wattage the larger the voltage output. For this Instructable I got a 65 Watts light bulb.

Most CFLs have a similar circuit topology. All of them have 4 wires coming out of them. The wires are in pairs, and each pair connects to a filament inside the light bulb.

The CFLs I came across have the high voltage on the outer wires. You only need to connect the outer wires to the primary coil of the flyback transformer.

You will find a comprehensive description of CFL circuits on this page

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Chinese12 hours ago
It is very interesting,but I think it is so dangerous.
I understand that occasionally the lead configuration in the CFL will be different, but the one I got looks nearly identical to the picture you posted. By the end of the project, I wasn't getting a spark any longer than about 4 or 5 millimeters, and so I started troubleshooting. As far as I can tell, everything was hooked up properly- I'm confident that I identified the correct terminals on the flyback. I used a multimeter to check the voltage output of the CFL circuit (expecting it to go up in flames- the meter was only rated for 600V) and instead saw a value that started around 120Vdc and dropped as soon as I hooked up the meter (like a capacitor would have). I decided that I must've hooked it up to the wrong wires, but after checking voltages across all combinations of the 4 wires, the most I saw was a constant 120Vdc output across an outer and next-to-outer wire. What sorts of values should I be expecting at the "high voltage" leads? Do I need a different kind of CFL, or did I manage to fry something internal accidentally?

I am having the same problem but at about 270v (my wall plug is rated at 230v) I checked all of the pins, some combinations were like 10v, 40v and 270v (if I remember correctly)

Biotele (author)  nickglowsindark5 years ago
Hmmm, You may have a fried CFL, The transistors are just passing along the voltages from the rectifiers. Do you know how to test a transistor? Or.. the circuit is not oscillating and you need to add a feedback capacitor like in step 4.
I ended up having to add the capacitor to get any voltage at all out if it, and I know how to test transistors, but I'm afraid it's a moot point now, since a little bit more fiddling around resulted in an interestingly colored flame and a terrible-smelling apartment. I'll be picking up a new one later today probably and giving it another go.
pravinjoshi573 months ago
Can I get circuit with Tesla coil....?
pravinjoshi573 months ago
How can I connect it with Tesla coil made by my self...?
pravinjoshi573 months ago
Circuit is not working.....I conne t flyback with 40 watt tube light ballast...

Hey, so after completing this, how could you use this to power something else? like is there a way to connect it to another source?

volts

I got my hands on a 42W CFL. I keep breaking my Fly backs; the next one I get I am taking the core out and then winding my own, i am not going to have as big of a problem with hysteresis and less chance of burning out because I am only using one secondary and a higher gauge.

mlocke made it!10 months ago

I was amazed how well this worked. Good 'ible.

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Robotist11 months ago

Thanks for this document. My idea was to put a cfl driver and then flyback and finally connect it to cockroft walton multiplier. I found the required pins on the flyback and followed the instructions carefully. I did everything possible. Unlikely, the flyback didn't work. actually, I believe that adding the capacitor to pins 1 and 2 instead of filament wouldn't solve the problem. would you please explain exactly what pins should I apply to the input pins of the flyback?

will it kill you ?
hell yes.
maddog1014 years ago
Hey can somebody help me with how to get the flyback transformer off the circuit board of the CRTmonitor? i don't know if i should break the circuit board or what i should do. can somebody please help me!?
I USED A PROPANE BLOW TORCH IT EASIER LIKE THAT SINCE IT HEATS ALL THE PINS HEAT UP FAST, ITS IMPOSSIBLE TO DO IT WITH AN IRON CAUSE YOU'D HAVE TO GO OVER EACH PIN INDIVIDUALLY , I ALSO USE THE TORCH TO REMOVE MOST OTHER COMPONENTS EASILY, ALSO THE TORCH CAN BE SELF STANDING ON A TABLE WHILE YOU USE BOTH HANDS TO GUIDE THE CIRCUIT PINS ON THE FLAME WHILE PULLING THE TRANS WITH THE OTHER HAND.
i took a dremel and cut around each pin the used the iron.
OW! MY EARS HURT FROM ALL THE YELLING! Seriously, there's no real reason to capitalize an entire paragraph.
I just broke the flyback transformer off of the circuit board with cutting pliers. If you can't get it off with any other method, just break it off.
Biotele (author)  maddog1014 years ago
Break the board with a pair of pliers. Wear gloves and safety glasses.
Thanks, now that i have the flyback how do i find the primary and secondary leads?
For every flyback it varies, so you can't say that every flyback the same pin out configuration. Get a multimeter and set in the ohms range and test every pin until you find a pair with a reading at or close to 1 ohm. I have found two pairs of "primaries" so you will just need to test each one for the best HV output.
Eric8 maddog1014 years ago
sorry


Red Wire
_________
/.................... |
| 0 0 0 9 .......|
| 0 [|||||||||||||||||||]
| 0 [|||||||||||||||||||]
| 0 0 1... + + |
\_________|
Eric8 maddog1014 years ago
Red Wire __________
/ |
| 0 0 0 9 |
| 0 [|||||||||||||||||||]
| 0 [|||||||||||||||||||]
| 0 1 + + |
\__________|


this transformer :
Primary the "+"
Secondary min voltage "1" , max voltage "9"
the second wire the secondary coil is the big red wire that connect to on the screen.

i hope helped you,
can you help me now? please
i bought warm white CFL and this electronic plate output is 70volt, this is ok?
i connected this to the pins and "nothing" happend i connected right the pins are right, after it i smashed my transformer with hammer and saw i connected pins right! i dont know why it dont work, pliz help

Breaking the board isn't that good a method. A de-soldering pump usually does the job and saves a heap of hassle when removing the flyback from the board.
you should just,,, "Unsoder it". if you have a sodering iron, then just get it all hot and stuff, and melt all the soder around whare the flyback transformer is atached. i have no idea how big the flyback transformer is, so you might want some tweezers to grab it while that soder is still melted,,, so that you dont burn your fingers.
nascar31 year ago

Awesome & very cool.

bigowl44221 year ago
alright i have a board with 8 SPOTS 4 ON EACH SIDE, that originally connected to two heaters how do i use these
I was wondering, do you the switch board to run a Jacobs Ladder, or can you run the flyback straight from high output to ground with your normal 120 input from breaker box?
grim32712 years ago
So i got a 26 cfl and cracked in and got the circuit

4 pins 2 on each side i have

J5-6 on a pair
J3-4 on the other pair.

I have NO idea what to do now. Any help please?
probably a little late but assuming 2 of those j's aren't for input voltage you probably have yourself an electronic ballast more like what they use here: http://www.instructables.com/id/Elecctronic-Ballast-as-flyback-Driver-part-2-outpu/
let me make that a hyperlink for you...

                     click here
i want to build cockroach electronic trap from 9v dc 200mA out put votage 4.5 kv where can i get circuit ? pl help ...
it could... but if you want to run it off 9V dc id suggest a 555 timer circuit, they can be just as powerful running off of 12v dc as this thing running off 120-240v ac. (but these are easier to build... don't have to buy any specific parts)
i want to build cockroach electronic trap work on 9v dc 200mA peak voltage 4.5kv can this circuit help me ? can you suggest circuit digram for same ?
james346022 years ago
Why my CFL driver explode after driving a Flyback Transformer for 5 minute
I thing is resistor explode and it turn brown
look at what the resistor leads to. i has a resistor labeled "fuse" and i decided that a good, safe idea was to bypass it :)
Will it work with burned out CFL circuits? I'm not sure what happenes when they burn out, is it the circuit or the bulb?
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