Rich:
My statements about the RF resistance are results of simple
application of the "theory" of RF resistance as stated in Terman. I accept it
as the authority, despite its age. If you want to dispute that, then let's go
at it.
According to that theory, which attempts to account for all of the
skin-effects, the RF resistance, where skin-effect dominated (i.e. large
enough conductors) is proportional to (sqrt)p at any frequency. In other
words, two different conductors, at a given F, will differ by (sqrt)p . I am
using 'p' for the normal symbol for resistivity, rho.
Based upon a DC resistance ratio, which is directly proportional to rho, of
64 for Nichrome, this equates to a ratio of 8 for R(VHF). I am claiming no
more or less than this.
The value you sight, 5.5, is not actually that far off, so I don't see
any need to argue that. I am curious, however, where you got the number from.
On a second point, it is NOT true that all of the RF current passes
thru the suppressor. There is clearly a direct path through C(p-k) to ground.
However, the relavence of this depends upon your assumed circuit model, which
is not at all clear to me. That is why I raised the question about it in the
first place.
Those of you who have been so engrossed in this issue for so long, it
is probably clear what you intend. But for those of us who are just trying to
understand the comments and remarks that get posted, we could use, if it
exists, the generic model which you (and any others who contribute to the
overall signal level) assume
If it is a relatively simple resonant circuit (less than 5 or 6 poles) then
there is really no argument. We can analyze it quite accurately by several
different methods, and that analysis will clearly show the effect of any
component contained in it. This includes any resistors which introduced as
lump sub-elements of other components.
73
Eric von Valtier K8LV
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