Joule Thief 101

[MileHigh]

PW:

One word:  copy-paste-agasm.

MileHigh

[EMJunkie]

Let's recap...

Tinman posts a schematic and two scope captures.

One capture shows a 90 degree phase difference between primary CURRENT and the open circuit secondary VOLTAGE.

The second capture shows a difference of 180 degrees between primary CURRENT and open circuit secondary VOLTAGE.

Tinman asks "which capture is correct?"

TK responds that the capture showing the 90 degree phase difference is correct, as determined by his empirical study (replication) and by his very lucid argument invoking Faraday by stating that the primary current is a fairly accurate proxy for the magnetic flux and that when the rate of change of that flux is at its minimum so will the secondary voltage be at its minimum.

Tinman also states that his empirical study demonstrated that the 90 degree phase shift was indeed correct  and, as well, also invokes Faraday in further support of his empirical results.

EMJ apparently disagrees with TK and Tinman and claims that the capture showing the 180 degree phase shift is correct, making one wonder if EMJ actually understands the question as presented.  It seems more likely he is arguing about the primary VOLTAGE instead of primary CURRENT, but perhaps not...

In EMJ's post 1585, he presents an ideal transformer graphic supposedly in support of his 180 degree phase shift assertion regarding Tinman's question that only further causes one to wonder if he actually understood Tinman's question, his schematic, his scope captures, or none at all.  The ideal transformer graphic presented appears to be discussing primary voltage (not current) and does not indicate an open secondary.

EMJ in his post #1562 appears to argue in support of both TK and Tinman via presentation of a graphic clearly stating that Faraday does indeed state that the induced voltage is directly proportional to the time rate of change of the magnetic flux.  Which, reasonably, also indicates that the induced voltage will be at its minimum when the time rate of change is also at its minimum (as both TK and Tinman reasoned in further support of their empirical data).

EMJ again appears to argue in support of both TK and Tinman by presenting the copy/paste of a textbook page several times now similar to his post #1658.  In that copy pasta is a "Figure 10.14".  The caption to that figure clearly states that the open circuit primary current lags the primary voltage by 90 degrees and that the primary current is mainly responsible for the magnetic flux which, therefore, also lags the primary voltage by 90 degrees.  This clearly supports TK's original response to Tinman's question. 

So, at this point I have no idea what it is EMJ is arguing for or against.

EMJ seems to argue that the empirical data both TK and Tinman presented is incorrect and that instead, the open circuit secondary voltage should differ from the primary current by 180 degrees.  But EMJ also presents data clearly stating that the correct answer is 90 degrees.

EMJ also apparently disagrees with both TK and Tinman's assertion that, from Faraday, it can be deduced that the secondary voltage will be at its minimum when the rate of change of the magnetic flux (as indicated by the primary current) is also at is minimum.  But again, EMJ posts material also agreeing with TK and Tinman's assertion that Faraday does indeed indicate the induced voltage is proportional to magnetic flux and that the primary current is indeed a fairly accurate proxy representative of magnetic flux.

Perhaps someone else can sort this out...

PW

PW - Clearly you have entirely missed the very specific point of the current debate as you completely circumvented it. Why?

You claim I have bought into question, Brads Circuit, scope shots of it, and the replications of it, when this is entirely fase! Why?

True or False: Faraday's Law Electromagnetic Induction does not and never will predict Circuit Reactance

Please just answer the question! Can you manage something like this:

False

PW

   Chris Sykes
       hyiq.org

[picowatt]

PW - Clearly you have entirely missed the very specific point of the current debate as you completely circumvented it. Why?

You claim I have bought into question, Brads Circuit, scope shots of it, and the replications of it, when this is entirely fase! Why?

True or False: Faraday's Law Electromagnetic Induction does not and never will predict Circuit Reactance

Please just answer the question!

   Chris Sykes
       hyiq.org

And just where and when did either TK or Tinman mention "reactance" in responding to Tinman's original question?

PW

[Magluvin]

Here is a video showing the effects of an oscillating magnetic field against transformer action.
How dose the oscillating magnet allow so much more power dissipation,while reducing the power to the source that drives the oscillating system.

Comments and thoughts welcome from all.


https://www.youtube.com/watch?v=mlb79xSh93w

Brad

One thing. Not sure.  Does it matter if the secondary is wound first under the primary or as you have it. Just wondering if the effects would be any different.

Mags

[Magluvin]

One thing. Not sure.  Does it matter if the secondary is wound first under the primary or as you have it. Just wondering if the effects would be any different.

Mags

Not meaning the affect to the sec from the resonating magnet stand, but the influence of the primary on the secondary. Ive read that if on the same bobbin that the sec should be wound first then the primary after.

Mags