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[Amps] Fwd: Voodoo "EMF' forces from grid current pulses

To: <amps@contesting.com>
Subject: [Amps] Fwd: Voodoo "EMF' forces from grid current pulses
From: 2 at vc.net (2)
Date: Tue Feb 4 11:27:44 2003

>Rich:
>
>       I am not well versed in the details of common transmitting tube 
>construction. I have much better things to do with my (always limited) time 
>than sawing apart toasted or otherwise abused power tubes.

 Out of sight, out of mind.
- Sand, the last defense of ostriches. 
>
>       I believe I have presented a generic example of the macro Lorenz 
>force 
>in practice that can occur between two current carrying conductors. This is 
>not an opinion - it is the LAW. Now if my model is not realistic, then it 
>simply does not apply and it is of no value. 
>
>       If you believe that 42A DC 

Who said this current was DC ?

>currents are flowing in ADJACENT PAIRS of 
>conductors anywhere, anytime within a tube and anywhere near the 
>parameters I 
>have used in my analysis, then show me( even at 42A the force will be well 
>under a gram) . 

The 42A-rms of RF related only to your assertion about vaporizing a grid.
>
>       By the way, if that 42A. (DC)

It is not DC.  What did I say that gave you the impression that it was a 
direct current?

> is flowing in the filament-grid circuit, 

It does not flow there.  It is an AC current between the anode and the 
grounded grid.

>where is it coming from?
>
The 10pF capacitance from the grid to the anode and the AC potential at 
the anode.   AC anode V = 3800v-pk/2^0.5 = 2690V-rms.  Since Xc = 
64-ohms, I = 2690V/64-ohms = 42A-rms
>
Eric -- you used the term "voodoo parasitics".  Mr. Rauch also uses this 
term.  Do you know Mr. Rauch?
       
>Eric von Valtier  K8LV
>
>P.S. It just occurred to me that if the filament wire is actually a helix 
>(only a moderately pitched one) 
>the adjacent B field will be much more 
>solenoidal than axial, which greatly reduces the Lorenz force on the adjacent 
>current carrying conductor by a great deal - further diminishing the effect 
>which you propose.
>        


-  R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K, 
www.vcnet.com/measures.  
end

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