Joule Ringer!

[gadgetmall]

Sweet .. your frequency has to be much higher . I noticed with these heavier  wire primary's (outside) using different power transistors the frequency is radically different . Seems the higher the frequency the less it likes shorts on the out (filament bulbs)put but the higher the voltage is and the less the current is . So lower frequency's make more current .I tried using resistors and it don't work for me . I had to double the secondary because it is what is connects to the base .I might try putting a bulb in series with the base today ..

Tk ? what is the diode doing ? Is it protecting the transistor and how can you get sine from half wave ? where are you measuring it? I need to go look at your video . can you post your link .

One more thing . When you are measuring current with a good meter . in my case i have 300ma setting and 10 amp setting, do we really need a resistor to read across? Will it not show a false reading because the  meter already has them built in . this is something i have never understood . When i check current i put the meter in series and it becomes part of the circuit . Some  say this is incorrect and i do not understand how when i was taught the meters have a shunt already?

[TinselKoala]

Hmm...
As far as measuring current with a DMM: Yes, you put them in series with your circuit, and yes, they do it by measuring voltage drop across a calibrated shunt. This means that the meter will have a series resistance when used as an ammeter: mine has 1.8 ohms series resistance. This can be significant for some circuits, and that's why sometimes you don't want to use them this way. For low power circuits, 1.8 ohms can be a lot of resistance!
Current is measured by digital meters in two ways normally: by looking at the voltage drop across a known low resistance (shunt) or by looking at the magnetic field the current produces (current transformers, Hall effect probes). For DC especially it is almost always done by voltage drop across a shunt but we've all seen and used clamp-on current meters for AC: cheap ones are current transformers and more expensive ones can use Hall sensors.
So inside the DMM meter there is a small resistance, very accurately known, and the meter is actually reading the voltage drop across this resistance and computing I=V/R to give you the current through this internal shunt.
You can obviously do this externally too, by using the meter's voltage function and your own, accurately known, external shunt. Or use the oscilloscope to look at the waveform across your external shunt and compute the current at each instant of a complex waveform.

As to my circuit variant of Lasersaber's one:....  The diode. Yes. Hmm. I could not get the neon to light at low input voltages without the diode. I tried many different diodes and resistors and capacitors.... the circuit is very sensitive here and I even went through a pile of 4002s to find the one that worked the best (lowest turn-on voltage for the NE-2). But to get the sine wave oscillation that makes the highest voltage, this is with the NE-2 and diode out of the circuit. With the diode I only measure half-wave at the load, as you'd expect. The incandescent lights up with or without the diode and NE-2.... weird.

I can't remember the frequencies this morning, just got up, but it can be all over the place. It varies greatly with applied voltage, and it also flips into several different stable modes, like 2x and even 1.5 x some base frequency at times.  I suppose I should measure it, rather than just looking at the pretty spikes on the screen. 

Putting in some resistance in the base leg cut my current by a factor of 5 in some cases...... from 250 mA down to 50 mA for example.... did make the turn-on voltage a bit higher but even the added 220R 3W made a big difference in input current, but the 1K+60 nF is working the best now. A .01 uF between C and E doesn't seem to do much for me, but between C and B, or B and E, it can have big effect or little effect, depending on input voltage.

There are subtleties to this little circuit that are fascinating, and it's not as simple as it looks.

My whole setup with this particular experiment was basically to see how necessary the magic rod ferrites really are..... I'm actually kind of surprised that the bead works so well, it's very cheap and low-quality material I think.

http://www.youtube.com/watch?v=11cBBjjd2qA

[xee2]

@ TinselKoala

If you remove the diode and the ne-2, you will see that your circuit is a slayer exciter. This is a resonant oscillator that automatically adjusts to the resonant frequency of the output coil. This is why you are getting sine waves. You should be able to light a fluorescent tube wirelessly when the circuit is oscillating. Thanks for sharing your results.

see  http://www.youtube.com/watch?v=54vdg4DzMfM&feature=plcp

[TinselKoala]

Thanks, unfortunately not wirelessly. I need to have just one wire hooked to the coil side of the "gap" where the NE2 and diode goes, with the collector side open. I guess it needs an antenna or something. It certainly makes the 1000 v p-p sine oscillation very nicely, and lights a straight tube or a CFL with a touch of a single wire... but not a glimmer wirelessly.

The sine oscillation is at about 245 kHz.

[xee2]

Thanks, unfortunately not wirelessly. I need to have just one wire hooked to the coil side of the "gap" where the NE2 and diode goes, with the collector side open. I guess it needs an antenna or something. It certainly makes the 1000 v p-p sine oscillation very nicely, and lights a straight tube or a CFL with a touch of a single wire... but not a glimmer wirelessly.

The sine oscillation is at about 245 kHz.

Have you tried just a tube? It is hard to get the CFL to light wirelessly with the circuit attached.
EDIT:  Opps, sorry I see you tried a straight tube. You probably need a higher output voltage (more turns).