STEORN DEMO LIVE & STREAM in Dublin, December 15th, 10 AM

[Omnibus]

That's indeed most interesting. I suggest you dig even further and try to find the most negative slope you can. Even the resistive OU is interesting it would be best if most of it was electrical so it can be pumped back into the main driver to keep it going perpetually.

The OU is in its essence electrical. We're using the resistor just to demonstrate it. So, I think, we can eliminate the resistor and pour that OU into a cap and then have a proper converter to feed it back into the input. Something like that. What do you think?

[blueplanet]

Not all the current probes are designed to handle current measurements beyound 100 KHz. Perhaps, this explains why you ended up with negative current (which gave negative power) when the operating frequencies reach certain values. If you need to do current measurement at radio frequencies, you should get a RF current probe, not ordinary low-frequency current probe.

[Omnibus]

Not all the current probes are designed to handle current measurements beyound 100 KHz. Perhaps, this explains why you ended up with negative current (which gave negative power) when the operating frequencies reach certain values. If you need to do current measurement at radio frequencies, you should get a RF current probe, not ordinary low-frequency current probe.

The current probe I have is not a low frequency current probe. It is Tektronix TCP 0030. Check it out: http://www2.tek.com/cmswpt/psdetails.lotr?ct=PS&cs=psu&ci=13420&lc=EN

[blueplanet]

Your load is just a simple passive high pass filter. The current proble should not give a negative reading at 41 Mhz, unless your current probe is faulty.

Also, you were using a pulse source to power the circuit. A pulse waveform contains a lot of RF signals, all of which carry power at above the fundamental frequency. A current probe is  in effect a low pass filter. There is a possibility that your current probe has "filtered"  out some of those RF signals!

If the current in your bifilor coil went negative at 41 Mhz for no reason, then please show us the input current waveforms at that frequency range.

I am still skeptical of the accuracy of your current probe.

[Omnibus]

@blueplanet,

Start here:

The current proble should not give a negative reading at 41 Mhz, unless your current probe is faulty.

Explain why a Hall effect-based current probe good for DC to >120 MHz Bandwidth should not give negative reading within that frequency interval if the current indeed has negative values (as is the case in this study).

This may also give you a clue as to why the rest of your concern (the probe being in effect a low pass filter) isn't viable.