Akula0083 Light No3 - Dual TL494

[EMJunkie]

Btw, if i connect the D6 diode the reverse ringing goes away

So first fix the circuit without that D6, the reverse ringing shows also when loading load to the output, but for simple sake dont hook up any load to the output of the ferrite, and first get the same ringing pattern to comfirm this circuit.

Thnx!

Greets JB

@JB,

The Ringing you are getting could be the natural ring down of the coil. Be careful not to confuse this with other effects. There are a few ways to check this and eliminate the Ring down of the coil, first, remove the core and check for the same oscillation. NOTE: It will likely be at a different frequency, as the LC, L being Inductance, and C the Coils Natural Distributed Capacitance, will have different values. The Effect will still be there under the same conditions.

EDIT: For clarity, I wanted to point out that the Natural Ring Down of the Coil is a little like the striking of a Bell, Hit it once and the Tone Vibrates on for a period of time....

A few other people on different threads have pointed this out and given the Natural Ring Down of the Coil many fancy names. Of course this is quite simply wrong.

All the Best

  Chris

[madsatbg]

Hello JohnnBlade
transistors BC / p-n-p / , on picture "Image" are drawn wrong.
Emitter can not be connected on minus / ground /.


regards

[MarkE]

This is right! Also, and importantly, one must take note of the Difference between Differential Negative Resistance and True Negative Resistance

Differential Negative Resistance: Current Never goes to or below Zero. Non Linear in its appearance.
True Negative Resistance: Current will go below Zero and theoretically can go well below Zero the more Current Drawn. Theorised to be Linear with Current Draw.

I did no see any signs of Negative Resistance in your scope shots.

Don't mix the two as they are quite obviously not the same and in fact not even similar! Its a confusing situation because most people, even scientists don't know the difference!

All the Best

  Chris

I think you are referring to someone else's scope shots.  I haven't posted any in this thread.  180 degrees phase shift yields the second form.  A high Q network at its SRF can provide such a phase shift.

[EMJunkie]

I think you are referring to someone else's scope shots.  I haven't posted any in this thread.  180 degrees phase shift yields the second form.  A high Q network at its SRF can provide such a phase shift.

Apologies MarkE, I was meaning JB's Scope Shots.

All the Best

  Chris

[Vortex1]

Btw, if i connect the D6 diode the reverse ringing goes away

So first fix the circuit without that D6, the reverse ringing shows also when loading load to the output, but for simple sake dont hook up any load to the output of the ferrite, and first get the same ringing pattern to comfirm this circuit.

Thnx!

Greets JB

Congratulations on the reverse ringing, something interesting happening there. Yes D6 is circulating all the power in the 12T winding and diode and using it up. Note that the 7T winding has no flyback diode.