Just my two cents for the heck of it:
I am pretty sure that if the base resonant frequency is 3 GHz, then you can only go up in frequency to get a harmonic resonant response, and that itself will be attenuated. You can't get lower resonant responses, that doesn't make sense.
The only thing that you can do is excite the toroid with a square-wave-type signal and line up an odd harmonic in the signal with the 3 GHz base resonant frequency of the toroid in an attempt to get a "rise" out of the toroid. However, the amount of spectral power at 3 GHz you can get from a standard bench function generator is presumably very very low. Then on top of that, the chances of anybody having a scope that can even see 3 GHz is probably close to zero. In other words, with such high frequencies, the toriod will look like a dead parrot no matter what.
The fundamental (no pun) point being that the toroid can only potentially resonate at harmonics above 3 GHz, nothing below 3 Ghz.
good luck
Thank you for adding your perspective.
This is basically what I am saying, but from a different point of view.
Yes, you are correct in that the torroid itself cannot resonate with the JT.
but the JT can resonate with the higher (attenuated) 3Ghz freq.
I worked the equation backwards to find those frequency nodes that would do so.
suppose we chose (from my example) the 22.872Khz node,
and chose a transistor that switched in linear mode at this freq.
the 3Ghz resonance would be the 6th (odd/half-wave) harmonic of the JT's operating frequency.
The result in magnetic amplitude during the "charging" of the ferrite, is an increase.
Not only the tiny amount gained by constructive interference of the harmonic signals.
But also, due to the changes in reluctance through the ferrite at the 3Ghz frequency.
[prepare yourself for techno-babble, if you don't like math, you can skip to the next msg.]
reluctance (R) is defined as Ampere-turns per Weber, or as Turns per Henry.
the particular definition you know and use may depend on which country you live in or
which profession you were educated to perform in.
Either way, the value is the same.
R = Magneto-motive force in Ampere-turns / Magnetic Flux in Webers
these are fancy words, what does this mean?
Flux = NI ; N is # of turns, I is current
or = field strength * circumference of the torroid
this is generally applied in a similar manner to Ohm's Law.
and in fact, in the copper coil, and in an abstract observation, throughout the whole of the electronic portion of the circuit, it is equivalent to Ohm's Law, at any point of observation.
the magnetic induction, however, has an inverse proportion to the electromagnetic flux.
flux, in the magnetic spectrum relates to the Weber.
Defined as Volt-Seconds, or Maxwell's.
luckily for us, Maxwell did the work of combining the magnetic flux with the electric.
I could not do that..... Maxwell should get a statue next to Lincoln....
electric flux = charge / permittivity
faradayian induction combined with Gaussian induction presents, what J.C. called a "deamon".
( I intended every bit of that pun! lol )
without boring everyone to death,
we get a 0 in the numerator in the equation for reluctance,
as it pertains to the materials property of the ferrite torroid.
What happens when you put this deamon in a box? well, if we were to hit the exact frequency,
according to Maxwell, magnetic flux increases infinitely for a finite period of time,
the collapsing field burns up and destroys our circuitry.
This is discussed in great detail by Steven Mark, and BruceTPU in much greater detail that I could relate to you in words.
Luckily for us, the rest of the JT circuit (battery, transistor,wires, LED, Cap, Etc)
represents a secondary impedance, which when we adjust for this, we are not exactly resonating with the 3Ghz, but slightly lower than. The resonant wave-form will appear, with increases in amplitude, out of phase with the actual resonance of the ferrite, causing (some small bit of)
destructive interference. Allowing us to continue operation of the circuit, at nominal values,
without excessive buildup of energies in parts of the system.
What this means for us, and our meters and scopes
is a decrease in current from the battery half-cycle, and an increase in current from the field collapse
during the other half-cycle. this reflects between the base and ground, and back into the coil the following half cycle. One could say this is the reason for less current draw through the transistor.
or by the other perspective, one could say the increase in voltage associated with the drop in current
resulted in a decrease in electric flux. Either perspectives are (partially) correct.
except in that, if we couple to this with a secondary transformer coil, the primary circuit is not affected by the draw on the ferrite's field.
The field strength, in resonance, dominates over the coil, by a great deal.
current in the primary JT coil does not increase back to its' non-resonant levels.
the secondary can then be used to power another JT-type torroid, or a load.
such as a motor, or heating element for direct power transfer measurements
