Joule Thief

[TheNOP]

hmmm.
the instantaneous current.
I have seen the formula that uses the instantaneous current. I think it is more accurate. It probably assumes rms.

I suppose in the states instantaneous is 1/60th of a second. Other places it is 1/50th of a second.

In one of my coils an instant is a lot shorter in time. It is 1/52,700 part of a second.

I made a mistake in my table. I forgot to multiply the watts of one pulse by its frequency to get the total watts for one whole second. I fixed it, but I will recheck it before posting.

I am still pondering this.

When current goes back and forth, the magnetic flux pulses. Only the voltage is measured. So, when the current goes back and forth the voltage pulses.

Why can't the current be directly measured?

how can you count electrons that pass from one side of a virtual gate to the other side ?
the easiest way is to measure the voltage accross a know resistance that is connected in series to the source.
a ampmeter is doing this.

Does the magnetic flux pulse higher when there are more amps?

the current does not create a mag field, the current flow is.
that being said, yes, more current flow create bigger mag field.

And is that amps drawn?
If they are always available, then they should be showing up in the meter, but they only show up when they are being used?

And when they are drawn where do they go if what they are doing is going back and forth?

If some of them are converted to heat or light there would be fewer available for the return trip. But what return trip?

If I use 250mA from my 1.2 volt battery, the volts and 250mA are available to go through the wires of the primary. They do. And they do this on a one way trip to the other side of the battery.

But on their way, they jiggle and jump a lot.

The jiggle and jump is reflected in the pickup or secondary wire which lights leds and now fluorotubes.

What is the amps draw?

It cannot be more than 250mA since that is what is coming out of the battery, no more is available for use.

see  previous comment about current flow.
current can be compared to a pump + a pipe, in lots of ways.
the water in the pipe does nothing by itself.
you need pressure and something the can displace the water.
you can have pressure alone, but if the water is not allowed to move, there will be no water flow.
if the pump can only dissplace a small amount of water, even if you have a lot of pressure, you will have low gallons per minute output.
the way you can measure the water output is to place a relatively low resistance(flow meter) to measure the working force against the resistance.

with plused DC the current only goes in one direction, the fact it is pulsed does not change that.
unless you are dealing with pure DC, you can not assume that the amps peek is reached instantaniously or that it is always at it peek.
the time constant must be part of the equation.

with AC the current flow direction change.
but think of it as if you were flipping the battery + and - at a given frequency.
the charge imbalance of the battery still do the same work not matter whitch way it is connected.

for a pure sine wave .707 is the constant that will calculate the true RMS value.
but that constant change with the wave form.
if what you are measuring is not a perfect sine wave you can't use peek * .707 = RMS
you need to find the proper constant value for the wave form you have first, and that is not simple.

[hazens1]

Here's the Diagram for my 1 inch 5/$1 Goldmine Toroid Fluorescent JT Circuit. I modified Xee2's diagram to match my setup. Thanks Xee2!

Check out the last pic. I took the 1.6 watt tube from the night light and put in in the circuit. Pretty bright! 

[xee2]

@ hazens1

Very nicely done. Is that really a ten ohm base resistor?

[Pirate88179]

@ hazens1:

Nice Job there!  Floro tube on a JT circuit.  Xee2 was the first I know of to do this on a hand wound JT and now, you have done it.  Excellent work! 

Xee2:

Great circuit there!

@ All:

Youtube is STILL down for maintenance so I have to wait to upload my next video.

@ Wilby:

Thanks man, I appreciate that.

Bill

[hartiberlin]

Hi hazens1 ,
nice light output at the U-shaped tube.

How much current are you drawing in this picture from
the AA battery ?

Many thanks.

Regards, Stefan.