Author Options:

2n3055 flyback transformer driver diagnosis. - Showing some sign of life Answered

Hello again instructables!

Now I've finally gotten my circuit completed. 

However, I can't seem to get it to work.

I've tried to follow this : https://www.instructables.com/id/2n3055-flyback-transformer-driver-for-beginners/

I'm using the same transistor (2n3055) - I am however using an older flyback transformer. (see the pictures)

I've also made this circuit without any success : https://www.instructables.com/id/Flyback-Driver-circuit/ (With another transistor than what he uses.) 

I've also tried to 'test' the circuit using only a 1:1 transformer instead of the flyback to see if I got some kind of high pitched noise. (EDIT)
After a tip from iceng I am now able to get a high pitched sound. But I am still not able to draw arcs.

With my minimal knowledge, I've tried to search through the internet and this site for ways to troubleshoot it, and I've pretty much tried everything I can think of.

Things I've replaced / tested

- New standard wires 
- Other wires for the windings
- Less windings, more windings
- Different transistors (Like I mentioned I'm currently trying with a 2n3055, I've got about 10 of them, so I've tried different ones.)

- Different powersources : Batteries from 1.5v to 9v.
- Switching around cables on the windings to try to get the right polarity
- Checked the resistors. They work just fine according to my multimeter.
- Checked the transistors. They work just fine according to the multimeter.
- Checked for continuity where it make sense that there is, and that seemed to be correct.

Hm, I think that's everything. If I've forgotten something essential, please let me know.

Here are pictures of the different circuits I've tried to make, and two circuit diagrams.

Edit: I've re-done my windings on the flyback, so they arn't quite as sloppy as they look on the picture.

Edit : Added updates.



Best Answer 6 years ago

Flip the polarity of the base drive coil.


I'm sorry. What?

English isn't my first language and I'm not really familiar with these kind of expressions.

what do you mean with 'base drive coil' ?

Thanks for your reply!

The wire going to the ( B ) base of the NPN transistor.
The wire going to the junction between the two 220 ohm resistors.
exchange the two wires and then try again.


Alright, I'll try that.

Will post results in about 10 min.

Thank you very much :)


Answer 6 years ago

Hmm, still nothing, thanks for the suggestion though!


Answer 6 years ago

Disregard that. I can hear a high pitched sound now. This is major progress!

And again, thank you very much!