Joule Thief

[jadaro2600]

@ jadaro2600

The voltage is created by the collapsing magnetic field. It is a consequence of the collapse, not the cause.

Coupling between coils should be considered as a result of changing current flow, not voltage.

Ok, now things are making more sense, thankyou.  It seems then, that it's less transformer action that's being usefull and more the logical physics that's being harnessed here - So then there is less transfers of current, per se, while the transistor is off.

depend on what you call "voltage collapse"
whatever is happening in the base coil, it is way much less then in the collector coil.
it is a need part for the oscilation, but not what give the voltage spikes.
turning the transistor on = shorting the battery poles.
the longer you short it, the faster you drain the battery.

do you have a scope ?

@TheNOP,

I'm sorry, no, things would be much clearer then, but alas I have none, and if I did, it would have to be a multichannel ib order for it to be useful.

I didn't actually mean voltage collapse, I meant field collapse, but it typed out wrong.  The ides is then that magnetic field collapses, then a voltage occurs,  but why is the voltage collapse occuring in such a way as to be of the same polarity as the direction of the current flowing, this doesn't make sense to me ... I thought it would be created in such a way as there would be a voltage collapse in the opposite direction.

Is there not a polarity to voltage?  or is it like I had suspected, just a difference between two points?

[xee2]

@ jadaro2600 


Voltage is a way of measuring electrostatic force between charges. It tells how hard an electron is pushed or pulled as it is brought near a bunch of charges.

[jadaro2600]

A second thought, or third;

If we're getting these voltage spikes on recourse from the transistor being shut off, then all voltages picked up, from secondary coils, are then an effect of the current of the current being cut off as well, ...then how is it that an MK2 coil, or a 7,7, etc is getting results as it is could not be made better by ...

Winding the coil to collector be wound Bifilar with the secondary and the coil to base being wound, either under these with less winds, or over this, in some small section of the toroid...

By this I mean, wind bifilar all the way around, while using one of these for the collector and one for the pickup coil, and then adding a number of turns on a third wire for the coil to base?

[Koen1]

Ok, now things are making more sense, thankyou.  It seems then, that it's less transformer action that's being usefull and more the logical physics that's being harnessed here

Ehm... is transformer action not a great example of logical physics? I think I don't follow your statement...

- So then there is less transfers of current, per se, while the transistor is off.

Transfer of current between what? Between source and circuit there should be zero transfer of current when
the transistor, used in this case as an auto-switch, is off. Logically, in that phase any "transfer of current"
between the primary and secondary will not be drawn from the unconnected source. But that "transfer of
current" is still induction, is it not? Be it electromagnetic (via the flux core) or direct (wire to wire)
induction, still induction... Right?
If you think I completely missed the point you were trying to make, please tell me?

The ides is then that magnetic field collapses, then a voltage occurs,  but why is the voltage collapse occuring in such a way as to be of the same polarity as the direction of the current flowing, this doesn't make sense to me ... I thought it would be created in such a way as there would be a voltage collapse in the opposite direction.

And why did you think that, if I may ask? (yes sorry for the annoying question )

Is there not a polarity to voltage?  or is it like I had suspected, just a difference between two points?

Ehm... perhaps I misunderstand your remark, but yes, there is polarity, it is positive or negative, and yes, that is just a relative difference in
potential between two points. I fail to see the problem... ?

Regards,
Koen

[Pardon]

I just wound a new bar last night it has 21 turns wound first then 7 turns wound on top of that. all wires are wrapped close and tight and insulated between the layers. and centered on the bar. if i take the 7 turns and connect that coil to the collector and the 21 turn coil to the base i get almost all battery voltage going to the trans. plus the led is very bright.  if the coils are reversed i only get half the voltage and the led is dim. i think if i used a fully charged battery it would blow the led it is that bright. it also ran all night with very little battery voltage drop. what i don't understand is that the voltage measured at the led but after the diode is a small minus voltage like -.04 volt.

i think i like bars they are so easy to wind and seem to work just as good.