impedance matching in the tpu

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darkspeed

impedance matching in the tpu « on: 2010-06-18, 20:11:01 »

Newbie

Posts: 812

Some random thinking

As i understand it.. in a tube amplifier the output stage is high impedance and must be impedance matched down to X-ohms to drive a voice coil.

But because of the impedance matching transformer the output frequency is limited. ( and any caps across the input )

I know in a VTTC there is no impedance matching transformer and the output stage drives the primary directly..

And as i understand it the current in the primary is limited by the tubes ability to conduct ( high resistance )

Then at one point he says his output transformer can go to 245khz which seems high for a standard tube audio impedance matching transformer

Any thoughts on this guys?

Grumpy	Re: impedance matching in the tpu « Reply #1 on: 2010-06-18, 20:55:30 »
Group: Tinkerer Hero Member Posts: 4267 tExB=qr	matching the impedance would reduce or eliminate reflections from load back to source if that matters I always thought the square thing was a pulse transformer (long rectangle with four separated windings) and Sauron implied that is was as well.

darkspeed	Re: impedance matching in the tpu « Reply #2 on: 2010-06-18, 22:04:22 »
Newbie Posts: 812	Could the heating problem be due to reflected power as a result of impedance mismatch ??

MileHigh

Re: impedance matching in the tpu « Reply #3 on: 2010-06-19, 01:07:23 »

Newbie

Posts: 1888

In a small circuit running at audio frequencies the impedance match really only has to do with how much power you transfer into the load, there are no reflection issues. Certainly reactive inductors and capacitors can create phase angle changes which absorb energy and then pump it back to the source. However this is all "live" and all of the components see the "world" from nearly the same perspective.

Reflection only comes into play when the wavelength of your signal is 1/10 the length or less than the length of the interconnection medium. So in a coax cable carrying a cable TV signal you do an impedance match to maximize the power transfer into the load and to eliminate reflections traveling back up the cable.

When you see a partial reflection in a pane of glass it is because of the electromagnetic impedance mismatch between the air and the glass.

MileHigh

Grumpy	Re: impedance matching in the tpu « Reply #4 on: 2010-06-19, 02:27:49 »
Group: Tinkerer Hero Member Posts: 4267 tExB=qr	I would also add that any change in the refractive index is cause for radiation - be it optical or electrical. That said, in regard to the TPU, if driving a low impedance try matching it - if driving a high impedance, I don't think it matters.

poynt99

Re: impedance matching in the tpu « Reply #5 on: 2010-08-02, 04:12:55 »

Group: Administrator
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Posts: 3538
It's not as complicated as it may seem...

http://www.overunity.com/index.php?topic=8185.msg250763#msg250763

Somewhat related. Anyone have comments on Bolt's posts here? He makes some points on RE and power factor etc.

I wish he would come clean. Plenty of hints strewn about...question is, are they any good?

WW, Grumps, ION?

.99

---------------------------

"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa

Grumpy

Re: impedance matching in the tpu « Reply #6 on: 2010-08-02, 05:46:03 »

Group: Tinkerer
Hero Member

Posts: 4267
tExB=qr

Quote from: poynt99 on 2010-08-02, 04:12:55

http://www.overunity.com/index.php?topic=8185.msg250763#msg250763

Somewhat related. Anyone have comments on Bolt's posts here? He makes some points on RE and power factor etc.

I wish he would come clean. Plenty of hints strewn about...question is, are they any good?

WW, Grumps, ION?

.99

A while back he said something about needing several thousand dollars for a lab in order to build a TPU. Apparently he has never built any of the stuff he talks about.

VARS, reactive power and all of that sort of thing have nothing to do with the TPU. However, somewhere in the all that muck, was a mention of Newman's motor, which I believe is loosely related. RF is not RE - that is like apples and oranges.

BEP	Re: impedance matching in the tpu « Reply #7 on: 2010-08-02, 11:18:14 »
Newbie Posts: 2205	Bolt is a 'banner carrier'. Come up with a remotely plausible idea - or even interesting terminology, he'll grab it and run in circles to see how many will follow. When that idea fails, he'll drop it like a hot potato then jump from thread to thread looking for another one. For now, I'll wait for him to produce any circuit showing a zero power factor.

poynt99

Re: impedance matching in the tpu « Reply #8 on: 2010-08-02, 16:02:20 »

Group: Administrator
Hero Member

Posts: 3538
It's not as complicated as it may seem...

OK guys, thanks for your observations.

I had some real doubts myself when he first came on the scene 3 years ago.

Quite funny what has transpired there since I last read. I also really worry about folks that promote Don Smith and the Joule Thief as OU devices. (Not to mention asking for string-free money to start up a big lab to make it all happen) :

Good ol' Chef has given him the business though

nuff said.

.99

---------------------------

"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa

BEP

Re: impedance matching in the tpu « Reply #9 on: 2010-08-03, 04:22:32 »

Newbie

Posts: 2205

Hmmm.....

I think we have found a true source of perpetual motion..... Bolt

It (Bolt) reminds me of a wrist watch advertisement I saw in MAD Magazine about 30 years ago.

Full page add, across from the 90 day Pamper and 747 douche advertisements... Picture an elephant bellowing and very startled. Right behind the elephant is the salesman with one of his shirt sleeves rolled up to his shoulder. His arm is covered in a dark nasty looking sticky muck from the tips of his fingers to his armpit. On his wrist is the latest model Timex.

He has a big smile on his spattered face with a text balloon saying "and it is STILL TICKING!"

Bolt is like the watch only he is also the source of the muck!

MileHigh

Re: impedance matching in the tpu « Reply #10 on: 2010-08-03, 04:37:59 »

Newbie

Posts: 1888

I glanced at the thread and read a few complete posts by Bolt.

All of these experiments with coils and capacitors are really experiments related to "filters," which is just another name for an electrical circuit.

Between the input excitation and the output response there is a filter, think of a crossover network for a speaker system.

If you put sinewave on the input and a scope on the output and then sweep the sinewave in frequency then you can make measurements on the phase and amplitude of the output as the frequency changes.

There is a whole area of study called "linear network analysis," that's what Spice is based on. It turns out that we have figured out how to calculate the voltages and currents and frequency response in every part of a given electrical circuit using mathematics. So making the measurements will just be confirming what we already know.

There's no pot of gold to be found as Bolt is indicating. He is just pushing his mental envelope too far and failing to distinguish between his wishes and fantasies and reality.

MileHigh