Protonmom:

RAD E 4 is ref. in a paper published in 1907 in the same publication that Einstein published his works in:

http://arxiv.org/PS_cache/arxiv/pdf/0804/0804.3836v3.pdf


The above 2008 paper explains it way better than I ever could.

It deals with the laws of thermodynamics.

Google results where I located the paper:

"Rad. E. 4, 411 (1907). [4] F. Jüttner, Ann. der Physik, Vol. 339, Issue 5, 856 (1911). [5] D. Blanu˘sa, Glasnik Mat.DFiz. i Astr., Ser. II 2, 249 (1947). ..."



Bill

Thanks Bill,
That really didn't say much, huh?  I wonder if Stubbs might have used it in reference to his home-made heater they found in his shack?  I have no clue what that pdf was talking about.  Einstein, Tesla and Stubblefield were way above MY head.  Too bad they couldn't always talk in regular English so the rest of us could follow along. 

I may have been closer than I thought.

1 rad = 100 ergs per gram 1 electron volt = 1.6E-12 ergs ... 1 Gauss = 1E-4 Tesla 1 Gauss = 1E-6 Volt-seconds per square centimeter. Length and Area ...
www.iem-inc.com/toolcnvr.html

No telling HOW Stubbs could have used the Rad E4. 

Surely there is a scientist hidden away somewhere on this forum who would know exactly what Rad E4 was and how it was used back in the 1800's-1900's.

@ Cap-Z-ro,

Quote from: Cap-Z-ro on February 25, 2010, 07:12:55 AM
Not sure if it was specified how tight the coil must be wound on the core...and am wondering if coils can be made so that the cores can be interchangeable, for the purpose of experimental expediency.

Regards...

Looking at the patient, it seems that tidiness is a presquite to the stubblefield coil working correctly, if I'm right, I think the stubblefield Bifilar coils run at a lower voltage than at high voltage, it seems the bifilar function is to control the magnetic fields.
I read last night that stubblefield had a carbon resistance between the bifilar wires, so when the field collapsed, it still had some residual magnetism bouncing inside to restart the process after each cycle. Well it's a theory, one day we will know for sure.


The bifilar coils could be wound on a strong former, like a wooden dowel rod, covered by a rolled cardboard tube, perhaps it could be glued as the cardboard was rolled up, then when the stubblefield coil is made, the dowel rod is slid outwards, and several different metal rods could be tested to see how each performs.

jim
   

Quote from: protonmom on February 24, 2010, 09:38:52 AM
Another thing,

I forget who it was, but someone mentioned using annealed iron.  How do you make your own annealed iron?  Do you put it in a bon-fire and cook the heck out of it, and let it cool off?  Will that do the trick?  How does annealing make it soft iron?  And what are the properties of soft iron that make it important in the coils?  does annealing make the iron more magnetic?

Lots of questions.   Anyone have the answers?  Thanks in advance.

Soft iron will better because it will not remain magnetized , and are better at directing polarity N/S. Under magnetic stress it becomes a magnet .

In commercial electromagnet its the only stuff used .

Mark