Longitudinal wave research

[Bob Boyce]

Very nice Mark! Not the configuration I had pictured, but the results sure speak volumes. I am impressed with your attention to detail.

Bob

[Grumpy]

yup...

[gn0stik]

Mark, your coils are so pretty I sometimes have a hard time telling if it's a model or not, since your models are also very nice, and very realistic. This is getting very exciting, I must admit.

Grumpy peristaltic induction... very interesting indeed! I had never heard of that before. You never cease to amaze. Sorry I'm not contributing something more meaningful at this time.. I'm kind of beside myself reading all of this.

Rich

[Grumpy]

yup...

[MarkSnoswell]

Ok ... things are getting complicated with resoances and harmonics all over the place.

I have gone back to the bare toroidal coil to characterize everything very caerfully. THis is what I have found:

Tests on just the torroidal coil alone -- no core coils; nothing even close; just a single drive through a 1K resistor with a minimal length lead into the torroidal coil; no direct scope connections -- just holding probes in close proximity to minimize capacitive loading...

Results:
Single ended drive of open coil: Coil straight or in a loop (but not closed) I get just one resonance -- it is the anticipated 1/4 wave resonance. It's at aproximatly 6 MHz. Every indicator (voltage rise along the coil, phase angles) sows that this is the pure 1/4 wave harmonic with no spurious signals.

Single drive point into the close torroidal coil: Only one resonance present at the second harmonic 42 MHz. Probing voltage and phase around the torroidal circumference confirms resonance as second harmonic.


So -- I now know that this toroidal coil has a fundamental transmission length of 21Mhz. Open it supports the 1/4 wave harmonic at 6Mhz and closed it supports the 2nd harmonic at 42Mhz...


I will now do tests on the core coil alone -- characterizing any resonances I can see. However it is already clear that the system of two coils - toroidal and core coil - exhibits complex and novel resoannaces and that there is a tendancy to resonante in pairs of frequencies in the ratio of 1:3. ... why is that?


@Bob
Yes -- it's all in the details!  Not only do you have to know exactly what all of the classical behaviours are but you have to be very diligent and caerfull in examining the anomalies. I am determined to get to the bottom of this!