Joule Thief

[TinselKoala]

TinselKoala
here you have a few interesting Vids that show some interesting effects
as a builder yourself ,would you explain this acceleration in the second video
to some of our builders here working on acceleration effects and voltage increases


I know the second Vid [with the motor ] has other "snake oil" purposes ,but you also are showing acceleration under load,
it would be good to discuss this here,I know other builders respect your work.

Voltage  https://www.youtube.com/watch?v=FLsOCYPCvGc


acceleration  https://www.youtube.com/watch?v=9x2YfA9LU5s


When you have time and in the appropriate Thread ??


respectfully


Chet

The first linked video should be labelled "Current" rather than "voltage", since I am measuring the voltage drop across an inline current-viewing resistor to show the fact that the _current_ draw from the battery source is the same or slightly less with the 24 LED load _connected_  than it is with the load disconnected. This is a real effect and should be replicable by anyone with a similar JT. And, indeed, the video was done in response to some "oohing and ahhing" over the same "amazing" effect posted in another thread by a different poster using a different circuit (but the same operating principle). However, current is not power, power is not energy, and a real measured estimate of the input and output  _power_  should be done by the usual, correct means, before any conclusions may be confidently drawn.

The second video's acceleration effect _may_ be an artifact caused by the inadequate "measurement" of the quantities concerned. All kinds of strange things can happen when you are in the near-field of a relatively powerful source of EM radiation (inside the black box), and improper measurements can lead one to make improper conclusions.  As Richard Feynman may have said, "The easiest person to fool is yourself."

[Groundloop]

Hi,

Can anyone help me with a answer to this question?

Regards,
GL.

[MarkE]

Hi,

Can anyone help me with a answer to this question?

Regards,
GL.

Your inductance meter measures the amount of voltage it takes at a test frequency to drive a reference current through the winding.  The second winding has a high mutual inductance with the first winding as it is wrapped around the same toroid.  But wrapped as it is around the second toroid, it has a lot of uncoupled inductance.  So:  Closing the switch makes the measured inductance go down, but not as much as if the second coil did not also wrap around the second toroid.

[Groundloop]

Your inductance meter measures the amount of voltage it takes at a test frequency to drive a reference current through the winding.  The second winding has a high mutual inductance with the first winding as it is wrapped around the same toroid.  But wrapped as it is around the second toroid, it has a lot of uncoupled inductance.  So:  Closing the switch makes the measured inductance go down, but not as much as if the second coil did not also wrap around the second toroid.

MarkE,

Thanks, I have set up a test and the readout on the L meter did go down to almost half when the switch was closed.
This confirms that it is possible to use this method to tune a oscillator to two different frequencies just by open or
close a switch.

Thanks again.
GL.

[TinselKoala]

Hi,

Can anyone help me with a answer to this question?

Regards,
GL.

I used the same numbers of turns as on your diagram: