The TPU uncovered? (A PROBABLE technique.)

[duff]

@duff - It's been many years since I was in a classroom, so I've had to really scrape the edges of my memory to recall much about reflection and I haven't had sufficient time yet to research it properly again. But the more I think about it the more I'm convinced we're not seeing reflection, as the kick appears on the leading edge of the pulse event. If memory serves, reflection happens after an event and may superimpose itself in such a way as to appear to be part of a pulse train. But we aren't necessarily talking about pulse trains here - a single pulse will show a kick. For it to be otherwise, we'd be looking at Einstein's "spooky action at a distance" and I don't think we're working in that realm.

@buzz

Sorry, perhaps I wasn't very clear when I posted about the reflections.

I was not implying that the reflection constituted a kick.
I meant to request that a effort be made to eliminate possibility of what  was being seen as a kick was really a reflection.


@Paul

At times it's difficult to discern between what is norm vs anomalyous.

I've been trying to model your test and compare the model against your results.

The following is what I've come up with so far.
I don't know if I've got the model right but the spikes are there, only the amplitude much lower in the model.







I used ngspice. Here's the netfile if anyone is interested.

Code Select Expand


paulDude kick analysis 2
* init, Vpulse, delay, Trise, Tfall, pw, period
v1 1 0 pulse (0 9.8 2ns 2ns 2ns 6.206u 12.412u )
l1 4 0 3m
l2 1 2 3m
l3 5 0 3m
l4 1 3 3m
k1 l1 l2 .95
k2 l3 l4 .95
k3 l2 l3 .95
r5 2 4 1e12
r6 5 2 1e12
r7 3 5 1e12
.tran .1us 24us
.end



-Duff

[buzz-ard]

@duff - Thanks - I understood. A simple way to eliminate/observe reflection was something I had been looking for. But I realize it's not the critter we're looking for here.

I'm about ready to get back to my bench and will also replicate Paul's demo, and maybe a couple of variations of my own.

[poynt99]

so there's been a tiny bit of comments about the kicks and the experiment, but that's it?

are you guys more interested in putting each other down and other such things

has no one any explanations, questions, comments, arguments, whatever?

is this how we get to the bottom of the kick mystery? (it's still a mystery to me even though others may not feel the same).

duff thanks for the modeling. what do you conclude from your particular (slightly odd) circuit and its results? is your circuit correct? why are you measuring between node 1 and 2? is anyone paying attention to this...pick up an error maybe?

i know there's more than this going on in the brains out there, c'mon guys post your thoughts.

[pauldude000]

@duff

Try it without extraneous components, just as I posted the experiment. No resistors. The opposing field itself limits the current draw. My experiment requires 2 pancake coils: 1 function generator, 1 oscilloscope.

Coil 1. The first pancake coil is wound continuous cw (clockwise) with a few inches of leads left.
Coil 2. The second pancake coil is wound continuous ccw (counter-clockwise) on top of the first.

This leaves only four leads. The inner lead of coil 1 is connected to the outer lead of coil 2. The outer lead of coil 1 is connected to the inner lead of coil 2.

I will post a pic of current flow.

Paul Andrulis

[pauldude000]

@all

Here is the coil current flow pattern. Remember, the current is flowing from the inside of the inner coil, to the outside, while the current is flowing from the outside of the outer coil towards the inside with the current direction arrows as indicated.



1. is the FG RED and probe connection
2. is ground for both FG and probe

Ignore 3 and 4. These were just for the original post, and were representative of which coil was being referenced.

By definition they are hooked in parallel, but in current flow they are parallel mirror opposites. That is why a regular schematic or simulation program can be worthless, unless it can differentiate pancake coil connections and action. If spice can, that would be great.

Paul Andrulis