Joule Thief

[jeanna]

Good morning everybody,
Welcome captainpecan.

Bill, there is another thing to remember about the transistor being off or on. If you leave the battery in and don't switch the juice off, you will drain .7v (or maybe .3v for germanium) because it is not quite off ever. It is a little open all the time. It is why my candle circuits with a switch outlast (by 20 days) the commercial circuits with a flicker. They use a transistor to make the flicker.

stprue, I have made them every way you can imagine, and probably more.

Until last week all my bifilar wraps were not crossed in the center except for the MK1, because it is part of the MK1 design to do that.
In fact, the MK0.8 is a MK1 in every way except it has a non crossed bifilar primary. It does well, but I think this double cross is solving the problems of looseness, I was having with the single crossed primary.

=====
Yesterday's tests were preliminary in some ways, but they did show the reciprocal relationship between the frequency and voltage output.
There seemed to be a bit uf uncertainty so I want to put this out  for everyone straight up, so to speak:
The base resistor is just the "rheostat" that determines the resistance which in turn determines the speed of switching.
It is the speed of switching = the frequency- that I was after for my switching transistor.

Today, I will return to the 2 tier circuit.
I can see it was a good idea.
I mean, if N Tesla did it in his patent, I guess I can do it too. 

N Tesla brought in a small amount of generated electricity. He didn't care. I could be from any source.
Then he used it to fill and discharge sparks.
These were low voltage sparks.
The sparks happened at high frequency.
Then, he used a transformer element with a lot of "very thin wire" in his circuit to raise the voltage.
For us this transformer is a second transformer.
But that is because the first one is part of the jtc and producing the switching frequency.

I am going to play with the 2 tiered circuit in this way.
First to create high frequency but maybe not so much voltage, then, second to raise the voltage by means of a transformer.
I will be using a toroid to do that, but maybe it is the wrong kind of transformer at this point. We'll see.

It is already 10 o'clock! Oh yes, that is AM. whew... 

jeanna

[jeanna]

@ Jeanna

In the picture I recently posted you will see one side of the coil having a double crossover and the other side does not.  On your Mk1 do you have a single or double crossover winding?  Also Do you have any pic's on your set-up? I'm a big visual learner

The pictures I have already posted (page489,490) are the best I have. But the details of the wind are too fuzzy for my MK0.4 or 0.8.
I need to get out the xo-laptop. It took awesome pictures. but later, I want to do some other things first.)

sorry.

jeanna

[stprue]

No prob.

[stprue]

@all

Did anyone try Artic_Knights idea back on page 496?  If so what were your results?

[TheNOP]

N Tesla brought in a small amount of generated electricity. He didn't care. I could be from any source.
Then he used it to fill and discharge sparks.
These were low voltage sparks.
The sparks happened at high frequency.
Then, he used a transformer element with a lot of "very thin wire" in his circuit to raise the voltage.

most transformers Tesla was using are not "conventional" transformers.

if it is a coreless transformer, very high frequency is needed for good coupling.
be carefull not to mismatch infos of both kind.
what apply to one might not nescessarly apply to the other in the same exact ways.

Tesla was relying on capacitive coupling in most of his experiments.
i am not saying he was not also using induction, he does, but to a lesser degree.

at very high frequencies, you can't have a core because a core at those frequencies would create too much losses.
Eddy currents and hesteresis losses.