Blocking Oscillator Transformer Multiforms

[jadaro2600]

Over the course of experimenting with the Joule Thief circuit, It's come to my attention that, after having done some research, there may be more than one thread needing dedication to understanding the way the Joule Thief works in order to have a component level understanding of what is going on in the circuit.  ( At least for other people's sakes )

I've personally built seven or eight different circuits in the last week alone, and while none of them are the same, they all work.  So I've started this thread to focus on Blocking Oscillators specifically, because after observations, there seems to be many setups that work.

A blocking oscillator is the minimal configuration needed to create a free running signal ( usually a transformer with two or more windings, a capacitor, and a transistor ) - the device configuration garnering its name from the fact that it's turned off for most of the duty cycle... but as one can imagine, this could be more or less accurate depending on the configuration.

More information can be found here - it's short, but makes a point: http://en.wikipedia.org/wiki/Blocking_oscillator

Below are images of my various Joule Thief circuits which incorporate different types of blocking oscillator transformer configurations ( multiforms ) - all of which work.

I welcome you to post your windings here - they seem to be relevant elsewhere here in the forum.

( in order )
jt_attempt_8.jpg is a linear transformer consisting of two equal lengths of same gages wire twisted tighly around one another.  The interesting part of this one is that, given the circuit configuration, the LED will flash - slower if the capacitor attached to the blocking oscillator is higher, and if it is lower, it will speed up to the point of being continuously on - and then not at all if the capacitance is too small.
jt_attempt_7.jpg is a the simplest form, with there being less current carrying winding than voltage collecting windings.  Note that this particular setup has to be activated by bridging the positive battery terminal with the positive lead of the LED.  Also, an interesting aspect of this circuit is that after a while it will turn off - there's oscilations I suppose that cuase it to eventually run out of 'steam'.
jt_attempt_4.jpg and jt_attempt_3.jpg are essentially wire type inversions of one another.  Where current is carried through the internal coil while voltage is collected across the outter coil.  This toroid type is formed by the current carrying loop while the voltage  collecting coil is wrapped around the current carrying coil.

[pese]

This schematic in Wiki is only an princip, for an circuit.
It must not used this way,
If if work,tis wa,  its not sure, not stabile,
depending of transitor (even not all from same type will work eachone9.
specially not over an temperature range from cold and higher
outside temperature, so you must first never use an transitor,
with (galvanic) open base in an circuit,
The base must have an
positive voltage from 0,7 to 0,9volt,  so that an small base current will
flow , so that this justify an fix collector=(working) current.
also in this oscillator.
Next:,  The transforme (back-) winding that produce the input energy to
base of the transitor have not to much (or not to less) windings.
Otherwise you must also justify ,  change (or add) some parts to reduce
this power. (if you use some unknow transformers of your Junk/scap - box)
The next is, (for high power blocking oszillators as inverters), you will use diodes,
base/emitter  and Collector/emiter to protect the transitor. again back-voltages
that can destroy them.

AT LAST you must use an small condensor , here 10uf -aso one 0,1ceramic) ,
between + and - ,   in the near of the transformer, so that all produced
frequencies (includin harmonic  RF)
will work to the transformer ,and not power back the supply wires (that will "rasiate"
-as an transmitter antenna!!) up to the  battery or to your power supply.
So you reduce RF radiating power in your rooms , that come aut from your wireings.

---
So that was my best english, if you have asls: Use my email

G.Pese

Over the course of experimenting with the Joule Thief circuit, It's come to my attention that, after having done some research, there may be more than one thread needing dedication to understanding the way the Joule Thief works in order to have a component level understanding of what is going on in the circuit.  ( At least for other people's sakes )

I've personally built seven or eight different circuits in the last week alone, and while none of them are the same, they all work.  So I've started this thread to focus on Blocking Oscillators specifically, because after observations, there seems to be many setups that work.

A blocking oscillator is the minimal configuration needed to create a free running signal ( usually a transformer with two or more windings, a capacitor, and a transistor ) - the device configuration garnering its name from the fact that it's turned off for most of the duty cycle... but as one can imagine, this could be more or less accurate depending on the configuration.

More information can be found here - it's short, but makes a point: http://en.wikipedia.org/wiki/Blocking_oscillator