Joule Thief 101

[MileHigh]

Im beginning to think that you do not read all of what is posted in threads MH.
I have told you ,and explained to you why and how !your! JT circuit is an inefficient circuit. I also posted a circuit,shot a video of the circuit running,and also the fact that replications have been made and posted here on that very simple circuit--the one below. Results are far more light output(measured with Lux meter)for less input energy. The ability to drain a battery down far more than !your! standard JT circuit. Due to the fact that it was just a quick throw together circuit,it could be made far more efficient than what i presented.

Brad.

Well, I told you that there were some mistakes in a posting of yours that included the same schematic a few days ago and there still are no dots on the transformer.

Im beginning to think that you do not read all of what is posted in threads MH.

I am reading the posts in this thread and I saw your posting and watched your related clip.  But you apparently are not reading all the posts in this thread yourslf because I am talking about something completely different.  See how silly this part of the exchange is with its silly mind games?

As far as your circuit goes, I see a resistor in series with the LED so to me that spells unnecessary power wasted in the resistor.  So I don't see that circuit as being better than a standard optimized Joule Thief circuit.  And of course there is no comparative data.  If you were convinced you were onto something you would present credible data comparing the two circuits.

It's not "my" Joule Thief circuit and you are only propagandizing yourself when you state, "I have told you ,and explained to you why and how !your! JT circuit is an inefficient circuit."

You connected your power supply to the circuit and ran it at a low voltage.  Presumably you have not run it with a battery and there is a significant difference between a power supply at low voltage and a battery at low voltage so right now you don't even know if it will drain a battery like you hope.

So, did you analyze a standard Joule Thief circuit running at a low voltage or not?  This is the second time I am asking you.  You made a cryptic claim that you did but I am not convinced that is true at all.   Did you do it or not?

What about a standard Joule Thief running normally?  Do you agree with my description of the operation of the circuit or not?  Are you going to describe how a standard Joule Thief runs or not?

What about the picofarads of gate capacitance in the transistor?  Is that relevant or not or do you continue to ignore that?

MileHigh

[Magluvin]

As far as your circuit goes, I see a resistor in series with the LED so to me that spells unnecessary power wasted in the resistor.  So I don't see that circuit as being better than a standard optimized Joule Thief circuit.

Didnt Brad show the circuit running without the resistor? I think it was him. Nobody else seems to be showing their JTs.  I have to look back and see.

Mags

[tinman]

Didnt Brad show the circuit running without the resistor? I think it was him. Nobody else seems to be showing their JTs.  I have to look back and see.

Mags

Yes,it is painfully obvious that MH dose not read the entire thread,nor pay much attention to any video's you post on your circuit.
Quote post 279 : A quick video on the circuit above.
The 10k VR has been omitted.
Also in the related video (at MH's request),i also show the schematic of the circuit with !no! resistor at all in the schematic. MH ask you to put up a schematic with each video,and also to give any information about the circuit in the thread. But even when you do this,he still gets it wrong,and once again gives incorrect information, along with incorrect assumptions about the circuit. No matter what you do to try and please him,it makes no difference--he still gets it wrong.

He is yet to take up my challenge.


Brad

[tinman]

Well, I told you that there were some mistakes in a posting of yours that included the same schematic a few days ago and there still are no dots on the transformer.

I am reading the posts in this thread and I saw your posting and watched your related clip.  But you apparently are not reading all the posts in this thread yourslf because I am talking about something completely different.  See how silly this part of the exchange is with its silly mind games?

As far as your circuit goes, I see a resistor in series with the LED so to me that spells unnecessary power wasted in the resistor.  So I don't see that circuit as being better than a standard optimized Joule Thief circuit.  And of course there is no comparative data.  If you were convinced you were onto something you would present credible data comparing the two circuits.

It's not "my" Joule Thief circuit and you are only propagandizing yourself when you state, "I have told you ,and explained to you why and how !your! JT circuit is an inefficient circuit."

You connected your power supply to the circuit and ran it at a low voltage.  Presumably you have not run it with a battery and there is a significant difference between a power supply at low voltage and a battery at low voltage so right now you don't even know if it will drain a battery like you hope.

So, did you analyze a standard Joule Thief circuit running at a low voltage or not?  This is the second time I am asking you.  You made a cryptic claim that you did but I am not convinced that is true at all.   Did you do it or not?

What about a standard Joule Thief running normally?  Do you agree with my description of the operation of the circuit or not?  Are you going to describe how a standard Joule Thief runs or not?

What about the picofarads of gate capacitance in the transistor?  Is that relevant or not or do you continue to ignore that?

MileHigh

What resistor?

[MileHigh]

What resistor?

Yes I watched the clip again and saw a different schematic in the clip as compared to the one you posted twice.  So you post a schematic in the thread twice that doesn't match what you are showing in the clip and you are giving me a hard time for not remembering your posted comment and the schematic shown in the clip.

In both the mismatched schematic and the schematic shown in the clip you can't be bothered to show the dot convention for the transformer and in the past I told you there was a major mistake in the schematic and after that I told you that you weren't showing the dot convention.  And of course in fact there are two major mistakes in the posted schematic.

MH ask you to put up a schematic with each video,and also to give any information about the circuit in the thread. But even when you do this,he still gets it wrong,and once again gives incorrect information, along with incorrect assumptions about the circuit. No matter what you do to try and please him,it makes no difference--he still gets it wrong.

"But even when you do this" my ass.  Look in the mirror because your self-documentation level is abysmal.  If you tried to pull that kind of nonsense off on a serious electronics forum they would probably be merciless and slice you to pieces.

Looking at the correct schematic, since you have no base resistor at all, it is pretty likely the case that you are passing way too much current through the transistor to switch it on.  So that could represent a significant loss in energy.  On the schematic you posted in the thread you state 50-60 turns and that length of wire and the associated resistance represents more lost energy during the transistor ON time.  I am assuming that that didn't even occur to you.

From looking at the scope traces and by doing a bit more simple testing you could have determined just how much energy is lost to keep the transistor ON during a single cycle.  Since you are making better efficiency claims about this setup you would think that you would want to try to at least make some measurements along those lines and see how that compares to a standard Joule Thief, but you don't.  The setup is right there on your bench and you could simply configure it as a conventional Joule Thief and then as a "zero resistance" Joule Thief and make some measurements, but you don't.  Welcome to Brad's world of stream-of-consciousness electronics.

I also notice there is still a decaying voltage/current waveform during the coil discharge cycle into the LED.  So the idea I floated about possible coil discharge efficiency issues due to that factor is also happening for this setup.  But just to play your game, I guess you are not reading the thread.

So all in all, I am not convinced there is anything better in your "zero resistance" Joule Thief setup and I strongly suspect that it would be less efficient than a regular Joule Thief because of excessive current used to switch on the transistor.  Beyond that, we have only anecdotal evidence for your claim - "You said so."

MileHigh