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Dismantled a CRT - Usable flyback transformer ? Answered

I've been reading up on Jacob ladders and tesla coils for a while now, and decided to try to make a Jacob ladder (the tesla coil just looks scary and advanced)

I've taken a part an old CRT. And I was wondering if you could tell me if it looks usable. 

I'm wondering slightly if I broke it when I removed it from the 'plate' it was stuck in. Pictures will show what I mean.

Sorry about the bad focus on the pictures. Taken with a phone, and it was slightly too dark for it to be able to take good pictures.

The brown cables looks like it's just fast in the flyback transformer, but I did not remove it.

I tried to get a good picture of the text that was on in case it means anything to anyone. 

Also, what I can gather by looking at this is that the red cable is the high voltage cable, and the low(er) voltage cable is either the grey, or white one. - Is that correct?

Thank you very much for your attention, and thanks for any replies.

And this site is amazing. I'm just amazed at how creative people are. 

Oh, and please let me know if I posted this in the wrong category



Jack A Lopez

Best Answer 8 years ago

Those pictures of your flyback transformer look OK to me.  Of course the way to tell if your flyback is good on the inside, is to wire it into a circuit, and then see if you can get scary purple arcs to come out of it.

There are a number of 'ibles in the related panel, on the right side of the screen there, ------------->
I'm going to recommend this one:
I like this one, because the circuit is not too complicated, and also because I like the "chicken stick" method for finding the high voltage return line.

Oh, and uh, be careful, because high voltage electricity is dangerous, and there are mines over there, and mines over there too, and those goddamn monkeys bite, I tell ya!

ZaekJack A Lopez

Answer 8 years ago

Thank you both for answering.

And yes, I shall be careful.


Answer 3 years ago

use that transistor and those resistors. If you want to find the HV. negative pin easily you'll need to take the circuit board and look on the place where the solder connections are of the flyback, look at the bottom of the circuit board and then you will need to find any connection of the flyback what is connected to ground or to earth. That is the high voltage return pin. You can find a lot more tricks on YouTube how to find the high voltage negative pin. And if you have an computer that is collecting dust remove the power supply and connect the green wire to the black wire and use the yellow and another black wire as ground. Yellow is 12 Volts and black is ground (negative) you can use that for your flyback. wind some coils on the flyback's core and one needs to be 5 turns (primary winding) and one needs to be 3 pins (feedback winding). Search for google on flyback driver 2N3055. Use the transistor of the television and the first pin is Base, pin 2 is the Collector, and pin 3 is your Emitter.

Good Luck!

You can follow me on YouTube:



8 years ago

Hello again. I'm posting here because I don't know if you'd rather I open a new question or just do it here.

I've gotten slightly stuck again, because I'd rather be safe than sorry.

On the picture that had a black 'tiny thing with 3 pins' I was wondering if that is a transistor. It was the thing placed closest to the / on the heatsink. (there were also some others, but they were smaller and closed around the heatsink.

I tried to google around for information about this ..thing, and it pretty much returned nothing. I could be doing it wrong though, not really familiar with googling for eletronical parts.

However, how do I ..find out what is where on the transistor? - I've tried to search for it here, but I could not really find anything (as far as I understand you use tags for searches, but I'm not familiar with the technical expressions used for such things, yet.)

And I've done the primary windings (15) There is also a picture of a red wire, that I was planning to use for the feedback windings, unless anyone has strong objections to that.

 And to give a general ide of how careful I'm beeing, when I tried to 'unload' the current that could have been in the high charge and generally anywhere, I used a chicken stick, and another chicken stick to poke the first stick. First one is made out of plastic, and the second is made out of three.

I've also got a few old car tape / radio players laying around, and an old CD player / radio. Is it likely that I could open them and use a transistor from there?

Also, I found a bunch of resistors in on the 'connection board'(where things are soldered on)
in the CRT I opened, a few of them beeing 220 ohm +/-5% and a few 20 ohm +/-5% ...As far as I've understood this, I can use them on this circuit, is this wrong?

Following this : https://www.instructables.com/id/2n3055-flyback-transformer-driver-for-beginners/?ALLSTEPS

The pictures here seem to .. resize. So I added links for the higher resolution pictures.





If what I write cause you to go "oh lord, you should never ever touch anything that uses electronics ever again" Then please let me know why, and what I'm failing horrible at, I'd really like to learn about this, as I've pretty fascinated with electronics since I was around 10 years old.

Thank you for any attention, feedback, warnings, and general / helpful / educational comments, even critique is welcome!



Answer 8 years ago

it is called a n channel mosfet yes it is a transistor you can get them from any
great electronics store like www.maplin.co.uk oh btw im nine years old. use
this information a npn transistor is normally turned off and a pnp transistor
is normally turned on.thanks christian


Answer 3 years ago

that isn't an N-Channel MOSFET but an line output transistor. pin 1 is the base, pin 2 the collector and pin 3 the emitter. And that is not true what you're saying with an PNP transistor, the emitter is positive and with an NPN it is negative. Please know what you say.


8 years ago

yep i would say that it is usable ican see that it has a internal capacitor so id say you got it from a pc monitor


Answer 7 years ago

Do all pc monitors have a transformer? if so, i can finally get one for all my projects!


8 years ago

theyre good and awsome cool pictures