Joule Thief

[jeanna]

Here is the pdf from motorola on their 2N3055

also a screenshot of a list that includes our 3 transistors
2N2222A .......... 300MHz
2N3055...............800KHz
2N3904...............300MHz

jeanna

[jeanna]

@ jeanna

All of the coils are very tightly coupled to each other by mutual coupling. Anything you do to the load on one coil is going to effect the other coils.

Thanks. I will have a peek.

One of the voltages in your data matrix is 140 volts. That should be more than enough to light up your neon bulb.

This is why I am puzzled. I fixed up another one from another high voltage cam circuit today. It doesn't light either.

I have asked before, but I just think there is something obvious to others that I am missing, like a diode or something.
Just staright across the 2 wires in the same 'across' way that the scope claims 140v or 125v today with a more tired battery, should do it, I believe. Especially as the curve of the wave is not very spiky at all. I really don't understand this.

I just put 16 superwhite leds in series which lit OK, and should require 56 volts.  8 light very brightly. I am sure I could satisfy the 'turn-on' voltage of at least another 8 or 16 so that is 24 or 32. if 32, that would prove that I have 112 volts, but I can see nothing on either neon.

I tried putting an electrolytic 100v 47uF cap across the battery where you usually have a high value cap, and still nothing.

I think I will try a 3 volt battery input and see what the scope says then test a neon there too.

Am I hooking this up wrong?

thank you,

jeanna

[stprue]

Does your DMM give you the same voltage readings?

[jeanna]

Hi stprue....
My dmm says 24ACVolts.

thanks,

jeanna

[xee2]

@ jeanna

This is why I am puzzled. I fixed up another one from another high voltage cam circuit today. It doesn't light either.

Most neons light at about 100 volts. But they can be made to light at other voltages also. Maybe the ones you have were made to light at 300 volts for the camera. This is a good source of neons if you want to buy some (all they show are not always in stock).


http://www.allspectrum.com/store/index.php?cPath=29&osCsid=ecb4b87c00ed60c698acdbdb263626d0