Language:
To browser these website, it's necessary to store cookies on your computer.
The cookies contain no personal information, they are required for program control.
the storage of cookies while browsing this website, on Login and Register.
 Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here: https://overunity.com/5553/privacy-policy/If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

Custom Search

### Author Topic: Electrical Faux Pas  (Read 25780 times)

#### z_p_e

• elite_member
• Hero Member
• Posts: 651
##### Electrical Faux Pas
« on: November 11, 2007, 09:04:15 PM »
The purpose of this thread is to identify and correct any errors and assumptions being made regarding basic electrical theory.

It is hoped that this thread may act as place newbies and non-electrical types can ask questions on this topic as well.

Cheers,
z_p_e

#### z_p_e

• elite_member
• Hero Member
• Posts: 651
##### Re: Electrical Faux Pas
« Reply #1 on: November 11, 2007, 09:42:07 PM »
Below are two errors that seem to occur on a regular basis, yet I have seen no one yet correct them.

These are fundamental faux pas and should not be propagated any further. They are:

1) Square waves contain all frequencies.

2) Transformers do not faithfully pass square waves. A 50% duty-cycle square wave applied to the primary of a transformer, will only yield a "short pulse" on its secondary. This is because most of the square wave time is spent on a steady voltage, either +V, or 0V... i.e. the wave form is hardly ever "changing" over time.

Both notions are absolutely false!

1) True square waves contain only odd order (integer) harmonics. A sawtooth wave form does contain all integer harmonics (one example).

2) All transformers have a finite bandwidth. Any wave form can be disassembled into its constituent sine wave components, a la Fourier. A square wave can be reasonably constructed using the first 5 sine waves, i.e 1, 3, 5, 7, and the 9th harmonics. The more harmonics applied, the more exact the resulting square wave shape will be. It comes down to transformer bandwidth, and what square wave frequency is applied to it. Too high an applied frequency, and the corners will start to become more rounded. In addition, the flat portions will begin to show "ripple" until finally, only the fundamental sine wave will appear. Too low a square wave frequency, and the flat portions will begin to tilt. At no time however between these two extremes, does the secondary exhibit a "short pulse-like" output. The transformer does not arbitrarily convert the square wave duty cycle to something other than what it is at the primary. Transformers therefore can pass square waves, and in fact any wave form faithfully, as long as the input frequency lies reasonably within the bandwidth of the transformer. If this were not the case, Audiophile tube amplifiers would not be possible.

#### hansvonlieven

• elite_member
• Hero Member
• Posts: 2558
##### Re: Electrical Faux Pas
« Reply #2 on: November 11, 2007, 09:59:34 PM »
Good boy z_p_e,

This sort of thing is sorely needed here. Thanks for starting this sort of thread.

Hans von Lieven

#### BEP

• TPU-Elite
• Hero Member
• Posts: 1289
##### Re: Electrical Faux Pas
« Reply #3 on: November 11, 2007, 11:16:06 PM »
Excellent!

What would be a correct description of rotating magnetic fields? This is something that irks me every time it is mentioned but I've learned to shut up about it.

#### z_p_e

• elite_member
• Hero Member
• Posts: 651
##### Re: Electrical Faux Pas
« Reply #4 on: November 11, 2007, 11:58:31 PM »
Here is something I posted almost a year ago. I think it still has relevance.

OK, first, I have not seen a practical down-to-earth explanation of what exactly a rotating magnetic field is. We all have said it, but what is it?

The purest example in my opinion, is to take a bar magnet polarized at the ends, and with a hole milled through the mid-point between the ends, the magnet is spun on an axis formed by this hole. This constitutes a constant magnetic field that is not only stable in magnitude, but one that is rotating as well. The distance between the ends of this bar magnet represent the diameter of a circle or toroid it would circumscribe, and it "splits" this toroid in half by virtue of its existence.

Of course we must envision the field as a ball-like shape, and remember that the poles can be rotated in any plane.

#### BEP

• TPU-Elite
• Hero Member
• Posts: 1289
##### Re: Electrical Faux Pas
« Reply #5 on: November 12, 2007, 02:35:38 AM »
Thanks!

As you probably already know. I can't agree with that description but that isn't the point or important at this time. For most practical purposes that is the way it should be considered.  What is important is that it is here and available for those who do not know. They can build upon that idea as they experiment.
The two things related here that I see:

1. The creator of the TPU has not used the term 'rotating magnetic field'.

EDIT>>> I stand corrected... There is comentary from the inventor and those around him that indicate a rotation of magnetic field is thought to be involved. Perhaps as ZPE described or maybe beyond my comprehension.

2. Alternating or switching a magnetic pole from one coil to another is not the same as the rotating bar magnet you have described, at any speed.

EDIT>>> Yes - pseudo would be a correct description. It works quite well with motors and generators. Indeed, this may be exactly how a TPU should work. I'm not sure at this point. However, using the two loops mentioned with a gradual shift of polarization should be very interesting. I'll try it.

EDIT>>>My intention was to create another reference point - not to start an argument. Such should be opened on another thread.
« Last Edit: November 12, 2007, 11:31:47 PM by BEP »

#### Mr.Entropy

• Full Member
• Posts: 195
##### Re: Electrical Faux Pas
« Reply #6 on: November 12, 2007, 02:37:31 AM »
Here is something I posted almost a year ago. I think it still has relevance.

OK, first, I have not seen a practical down-to-earth explanation of what exactly a rotating magnetic field is. We all have said it, but what is it?

The purest example in my opinion, is to take a bar magnet polarized at the ends, and with a hole milled through the mid-point between the ends, the magnet is spun on an axis formed by this hole. This constitutes a constant magnetic field that is not only stable in magnitude, but one that is rotating as well. The distance between the ends of this bar magnet represent the diameter of a circle or toroid it would circumscribe, and it "splits" this toroid in half by virtue of its existence.

Of course we must envision the field as a ball-like shape, and remember that the poles can be rotated in any plane.

There is no such thing as magnetic field that rotates on its axis.  The magnetic field is a vector field, which means it assigns a vector value to every point in space.  The value of the magnetic field at any point has the magnitude and direction of the force that the field would apply to the north pole of a magnet at that point.   This is the definition of the magnetic field -- it is just this vector field and nothing else.  In particular, it doesn't have 'lines of flux" that "move" or that are attached to magnets in any way, or that do things when they cross wires.  Flux lines are simply a convenient way to visualize the field.

A bar magnet has a magnetic field around it that is symmetrical around its axis.   Rotating the magnet around its axis, therefore, doesn't change the field at all, and no external objects will feel this rotation magnetically.

This was first shown by Faraday with his famous disk dynamo.  See:

Cheers,

Mr. Entropy

#### z_p_e

• elite_member
• Hero Member
• Posts: 651
##### Re: Electrical Faux Pas
« Reply #7 on: November 12, 2007, 03:25:38 AM »
Entropy,

I'm not sure what your post has to do with mine actually.

I was simply stating in it's purest form, how I envision a RMF. It had nothing to do with Faraday's paradox. You are talking about rotating a bar magnet on it's own axis a la Faraday's disk dynamo.

I was talking about rotating a bar magnet on an axis formed through the center point between the poles.... i.e. with a 6 cm long bar magnet, the axis of rotation is at (and perpendicular to) the 3 cm mark.

#### Mr.Entropy

• Full Member
• Posts: 195
##### Re: Electrical Faux Pas
« Reply #8 on: November 12, 2007, 03:47:32 AM »
I was talking about rotating a bar magnet on an axis formed through the center point between the poles.... i.e. with a 6 cm long bar magnet, the axis of rotation is at (and perpendicular to) the 3 cm mark.

Ohhhh.... nevermind then -- I read that wrong.

Cheers,

Mr. Entropy

#### wattsup

• Hero Member
• Posts: 2606
##### Re: Electrical Faux Pas
« Reply #9 on: November 12, 2007, 03:17:01 PM »
z_p_e

Thank you from everyone here that needs such help (especially myself hehehe) for this great effort. I have questions galore but let's start with what's on the table already.

I read Faraday's Paradox can see it has no bearing on the turning of the magnet on its width central axis, but on the length central axis. It is obvious that on its length the magnet is only turning into itself so the same effect is always maintained as it was when it is stationary. I can also understand why the magnet would produce a magnetic ball field or close to a ball field on it width central axis.

BEP says that switching between two coils would not produce such a ball field and this is also understandable since you are now creating two north/south poles and not one turning.

Now what if you simply had like the open TPU either four single wound (collector) coils in series or four double wound coils both in series to make two separate and parallel loops, and what if you simply changed polarities on either one set or on two sets in opposition. Would this be considered a ball field?

If not, can we presume that an artificial ball field with coils is impossible if the coil or coils do not physically rotate?

#### z_p_e

• elite_member
• Hero Member
• Posts: 651
##### Re: Electrical Faux Pas
« Reply #10 on: November 12, 2007, 04:58:44 PM »
Wattsup,

I think what BEP was referring to was the "artificial" creation of a RMF by two methods.

In general, there are 2 schools of thought on creating a RMF (there is at least one other known method using two wire loops in quadrature, but in regards to the TPU, these two only have been discussed):

1) wind several coils on a toroid ring and energize (or switch on) each one in succession in a circular pattern

2) wind 4 (or more even number) of coils in the same fashion as above, connect and drive them (as per Tesla et al) in such a fashion that the vector sum of the B fields create a "pseudo" RMF.

Method 1 imo deviates the most from a true RMF.

Method 2 is up for debate imo, but BEP (and others) say that it is not a true RMF (which is why I called it "pseudo"). This may be true, but until I try it myself, I won't say for sure one way or the other.

#### Vortex1

• Hero Member
• Posts: 518
##### Transit time
« Reply #11 on: November 13, 2007, 06:12:56 AM »
Quote
"One thing is an absolute fact, and that is that the electron transit time of tubes is very-very fast
compared to transistors"......Marco

Transit time is defined as:

1: The time taken for a charge carrier to cross a given path
2: The average time a minority carrier takes to diffuse from emitter to collector in a junction transistor
3: The time an electron takes to cross the distance between the cathode and the anode

Switching time is defined as:

1: The interval between the reference time and the last instant at which the instantaneous-voltage responseof a magnetic cell reaches a stated fraction of its peak value.
2:The interval between the reference time and the first instant at which the instantaneous integrated-voltage response reaches a stated fraction of its peak value.

sources: Modern Dictionary of Electronics, Third Edition
Principles of Electron Tubes, Bell Telephone Laboratories Series, D. Van Nostrand 1966

There seems to be some confusion on this forum of "transit time" vs. "switching time". With regard to vacuum tubes  and "electron transit time", the spacing between the electrodes creates a pure transport delay of information because the carrier electrons require some time to traverse the physical distance. This is not to be confused with "switching time" (which is more effected by interelectrode capacitance) as the information bandwith is not affected, just delayed.

As electrons start with near zero velocity at the cathode and are accelerated towards the anode based on the anode applied voltage, we then have at least two parameters that govern transit time, electrode spacing and applied voltage.

I understand (to some degree) the mechanism of electron transfer in a crystal lattice with doner atoms, but am baffled why this must be slower in all regards than tubes.

Transit time oscillators using semiconductors easily achieve gHz performance.

Perhaps someone can clarify why the claimed transit time of transistors is slower than tubes. Since I can adjust voltage and spacing, this seems to be a generalization. Your help appreciated.

Regards......V.

#### sparks

• Hero Member
• Posts: 2528
##### Re: Electrical Faux Pas
« Reply #12 on: November 13, 2007, 03:52:19 PM »
Sorry for messing up this thread
« Last Edit: November 14, 2007, 06:16:36 PM by sparks »

#### wattsup

• Hero Member
• Posts: 2606
##### Re: Electrical Faux Pas
« Reply #13 on: November 13, 2007, 07:29:27 PM »
@Vortex1

Could it be that tranistors have to turn on and off whereas a tube is continuously on and continuously pushing electrons from the filament to the plate. Transitors will produce a more uniform controlled speed, whereas tubes will produce speeds that are inherent to the actual randomness of nature itself. This would imply that the actual speed of a tube is not steady but often times much much faster and sometimes slower than a transistor but in the end, if the plate is considered to be a tank, it is getting filled faster.

The question you ask would be like asking why is a capacitor discharge faster then a straight DC pulse, in its ability to travel through coil windings. Geez, or is it?

@Sparks

I don't know about the black hole as a magnetic ball, but I have thought about this when considering how gravity works. I visioned a tiny black hole in the center of the Earths core and everything is falling into this hole, but the Earths mass, rotation and magnetic field is holding all or most of the mass out of the hole - for now. lol

#### wattsup

• Hero Member
• Posts: 2606
##### Re: Electrical Faux Pas
« Reply #14 on: November 13, 2007, 10:41:20 PM »
@z_p_e

Here is a question that has been bugging me about capacitors.

Most of the little devices I play around with are on DC. Now I have some capacitors that say DC on them and there is a plus sign on the top next to one of the terminals. Others  only give a voltage and a capacitance value, while others show the same thing but also have one side of the cap that indicates negative.

So can all these caps be used in DC or are there some that can only be used on AC current. Of course one would have to respect the voltage ratings or you will blow the cap like I've done many times. They actually sizzle. lol