STEORN DEMO LIVE & STREAM in Dublin, December 15th, 10 AM

[gravityblock]

Here's the video module of the SKDB e-Learning resources for the "M-H Curves and Magnetic Domains", http://www.3xw.steorn.com/skdb/e-learning/flash-promo/3.1/index.html   There are 20 slides in the flash presentation and you will need to push the play button for each slide.  If it stops playing, then push the play button again.

Look at the four images on this page that I've been trying to get everyone to read, http://www.tonmeister.ca/main/textbook/node428.html and compare it to slides 7 - 10 of the flash presentation.  They are both showing the same magnetization hysteresis loop.  Take note in slide 10 how they draw a dotted line with no explanation for this.  The dotted line is showing the near-linear positions of the M-H Curve and can be compared to the image on this page, http://www.tonmeister.ca/main/textbook/node429.html showing the near-linear positions of the M-H Curve for magnetic recording tape.  Both are near-linear and goes to the 0 magnetization mark on the graphs.

I'm also attaching a PDF file which says on the bottom of page 5, one of the current Orbo projects is a MH measurement system.

The M-H Curve is very important.  I hope this doesn't get pushed under the carpet.   

GB

[gotoluc]

Hi All,

Please see this latest update from JLN.

http://jnaudin.free.fr/steorn/indexen.htm#patent

This US government patent shows a method that can be used to reduce CEMF in toroid coils to zero by means of an additional coil wound circularly in normal fashion around the toroid's core and then wired in series or parallel with the toroid coil such that the current flow of any induce CEMF in each coil opposes each other. As long as the number of turns of this additional coil is equal to the number of times the toroid coils windings complete a full circle around the circumference of the core then it is possible to reduce any total CEMF induced in the coils to zero.

Here is perhaps a better explanation from JLN himself.

"The patent is very interesting because it say that in a common toroidal coil each layer are equal of one coil turn along the axis of the toroid. So, a one layer of toroidal coil is equal to a flat coil of one turn and thus it can catch or produce emf outside. So, to counter this, the only thing to do is to wound a one tun coil along the main axis of the toroid so as to create a magnetic field which nullify the virtual one turn coil created by the one layer toroidal coil... This is simple be this is a very important thing to do for canceling the weak CEMF induced in the toroid... "

This once again is an amazing find by JLN.

Regards,

Ossie

Humm

could it not be possible that JLN looked into this after I posted (Fed.10th NY time) that dual coils on a single ferrite Toroid core has a positive effect of reducing CEMF

Quite the coincidence I would say

Luc

[synchro1]

@Neptune

Your idea for the magnetic recording tape won't work for the simple reason that it's not magnetic. Hold a magnet up to the tape and see if there is any attraction. I tried this already and found that there is none. The magnetic recording properties of the tape have to do with data storage on a thin film on the surface of the tape, and not any magnetic attraction properties.

[gravityblock]

@Neptune

Your idea for the magnetic recording tape won't work for the simple reason that it's not magnetic. Hold a magnet up to the tape and see if there is any attraction. I tried this already and found that there is none. The magnetic recording properties of the tape have to do with data storage on a thin film on the surface of the tape, and not any magnetic attraction properties.

That is totally wrong.  My magnets are attracted to the magnetic recording tape of my audio cassette tapes and the 8mm audio/video tape I found.

I'll upload a video of my magnets attracted and attached to the magnetic recording tape if you like.  My magnets even attract to the magnetic tape from a distance.  The problem with the magnetic recording tape is going to be with the torque and it won't reach a high RPM which is very important in the Orbo.  The Orbo effect is based on the recording tape and a different core material is used in the Orbo to increase the torque and RPM.

GB

[Magluvin]

Why is that The core should saturate more so the current needed to fully saturate it should be less.

Well if you think about it, if the magnet is very strong it could overtake the saturation being made by the coil. So depending how strong the magnet is will determine how close it can be to the toroid.

Mags