Complete information on working SM style device.

[tao]

However, I dont' t understand why you have to calculate the "rise angle"

I think spherics has stated the numerical value of that angle:

... and the other 3 coils (X,Y,Z) will be pointing to wards the center BUT note the three coils will not be in a horizontal plane; they will be pointing 30 degrees upwards. 

Why would you think that 30? is not the correct and applicable value for the angle between the horizontal plane and the axis of coils X, Y, Z?

It is 30 degrees upwards from the horizontal, for the X Y Z coils, this is shown in my images.

[Rosphere]

It is 30 degrees upwards from the horizontal, for the X Y Z coils, this is shown in my images.

tao,

I respectfully disagree.  See my edited post above for verification.

I assume that the basic shape is a 'regular' tetrahedron and that all four coils point towards the centroid.  A 30 degree incline will give you an elongated tetrahedron.  Please open up your CAD file and take some point-to-point measurements.  Do you find any inequities?

[Rosphere]

... and the other 3 coils (X,Y,Z) will be pointing to wards the center BUT note the three coils will not be in a horizontal plane; they will be pointing 30 degrees upwards. 

Why would you think that 30? is not the correct and applicable value for the angle between the horizontal plane and the axis of coils X, Y, Z?

PS: I have once built a pyramid and I know that this 3D geometrical problems can be very daunting.

Yes, those are spherics words.  However, he started his post with four links about 'close packing.'  Close packing yields a 'regular' tetrahedron when connecting all four centers.

So, it appears that there is a discrepancy between the text and the close packing concept.  Until we get some confirmation from spherics, I will base my build upon the close packing angle of 19.5 degrees.  Others may use 30 degrees as explained in the text.

[omnispace]

@aleks

Take a look at this page:
http://www.r-type.org/static/twta.htm

"An anode voltage of 5 kV gives an electron velocity of 4.2 x 10*7 mso*-1. The signal would normally travel at c, the velocity of light (3x10*8 ms*-1), which is much faster than any 'reasonable' electron beam (relativistic effects mean that the electron mass actually increases as its velocity approaches c, so that achieving electron velocities approaching c is a complicated business), If, however, the signal can be slowed down to the same velocity as the electron beam, it is possible to obtain amplification of the signal by virtue of its interaction with the beam. This is usually achieved using the helix electrode, which is simply a spiral of wire around the electron beam...
...
The interaction between the beam and the slow wave takes the form of 'velocity modulation' of the beam (ie some electrons are accelerated and some retarded) forming electron bunches within the beam. The beam current therefore becomes modulated by the RF signal, and the bunches react with the RF fields associated with the slow wave travelling down the helix, resulting in a net transfer of energy from the beam to the signal, and consequent amplification. Since there are no resonant structures involved in this interaction, amplification is obtained over a wide bandwidth."

You can "slow down" a light-speed wave by making it run around in circles instead of a straight line.  This can be done without resonance, although I'm not sure how that will affect it as you approach the resonant frequency.  I believe that spherics' delay coil setup follows the same principles.

[sparks]

    Can anyone verify how Spheric's design solenoid windings need to be built?   I believe he was talking about
SM's design when alluding to timing coils. 
    Another thought I had was that if two plates are pulsed with the control pulse and the solenoid windings phase pulsed would this allow for tangential geometric orientation of the solenoid windings.  The collector winding then could be placed inside the dc pulsed plates.  Just a thought to cloud the thread.