Rotating Magnetic Field's and Inductors.

[MileHigh]

The CSR at the emitter weakens the turn-ON of the transistor because it decreases the base-collector voltage.  Oh well...

The other difference I see is that you substituted a battery for the previous 100Ω resistor across the recovery cap.
Moving the diode on the other side of the cap does not make much difference.

I am not quite sure what you mean by decreasing the base-collector voltage?  Perhaps you meant the base-emitter voltage?  If that's the case it's no problem because the function generator is "bouncing" along with the top of the CSR potential.  However, in my previous posting I express some concerns about that in general.

I think having a battery instead of the 100-ohm resistor is preferable for measuring the output power.  You reduce the affect of the diode drop in the basic output power measurement like that.  So I think a conventional "JB charging battery" configuration will be fine for his test.

[verpies]

I am not quite sure what you mean by decreasing the base-collector voltage?  Perhaps you meant the base-emitter voltage?  If that's the case it's no problem because the function generator is "bouncing" along with the top of the CSR potential.  However, in my previous posting I express some concerns about that in general.

Yes, base-emitter. Good catch.
Thanks

[tinman]

If the FG's ground was at the circuit ground thene CSR at the emitter would weaken the turn-ON of the transistor because it would decrease the base-emitter voltage, but since you have the FG's ground at the top of the CSR, then that problem is mitigated.  You FG is "shaking" at little by the CSR's V_DROP, though.

The other difference I see is that you substituted a battery for the previous 100Ω resistor across the recovery cap.
Moving the diode on the other side of the cap does not make much difference.

You recovery circuit still will not operate at full efficiency because C2 is not empty before each "flyback" pulse.  It just sits at the voltage of the battery.
Only an empty capacitor can absorb the "flyback" pulse with the most efficiency.

P.S.
Maybe you do not have a stiffening capacitor C1 but you should in a pulsed circuit.  It should be connected with thick short wires to the point where the CSR connects to the circuit's ground and to the positive side of the coil.

Verpies

I think you have my DUT mixed up with Luc's, as I have never had a recovery cap with a 1K ohm resistor--I have always had the second battery recieving the recovered energy.

[tinman]

Brad:

I am assuming that you are going to place a miltimeter across the CSR to measure voltage to measure the average current draw from the source battery.

It's purely a question of personal taste but I think my preference would be to put the CSR above the transistor and then have the scope and function generator ground be the same as the source battery ground.  Then have a "floating" multimeter across the CSR.

That way the scope, function generator, and the battery array share the same ground and they don't "bounce" relative to each other like you have in your existing schematic.  The way it is set up right now you can have a teenie amount of AC coupling between the battery array and the scope + fucntion generator.  You are also putting what amounts to an AC load on the top of the CSR because it has to make the whole scope and function generator "bounce" relative to the batteries.  Presumably the batteries will be AC coupled to the floor or table, a kind of virtual AC ground reference.  There is probably a slim possibility that the small amount of AC coupling will affect your results.  I can't tell you for sure because I have never done that.

MileHigh

Yes, I will be using multimeter to read the voltage across the CVRs. One on the input, and one on the output.My DMMs actually have a higher resolution than my scope, as they go one decimal point of a milivolt, where as the scope dose not. At the low current levels, the scopes mean V across the CVR seems to jump up and down in 4mv lots, where as the DMMs go up in .1mv lots, and the DMMs are much more stable.

My wife and myself stayed out a bit late last night, so I didnt get much done.

Also I agree that the SSG type circuit will do just fine for this test.


Brad

[gotoluc]

Here is my new test device which uses the coils flyback to do work.

Link to video demo: https://www.youtube.com/watch?v=K8kwdrHCyig

Same observation, it's more efficient with the coil and magnet rotor.

Luc