On Thu, 13 Jan 2011 16:18:35 -0600, "amdx" wrote:


The article's focus is on matching a crystal radio tank to the antenna,
So as a general statement, the tank is a high impedance (mostly R)

Hi Mike,

There's your first mistake. Tank Z is never, ever "mostly R," or you
wouldn't be able to make the Q claim of 1000 (or even 10).

Please note the distinction between Z (which includes R) and R in
isolation. Further, read Terman's material on Tank Circuits in his
classic "Electronic and Radio Engineering" to clear up the clouds that
obscure the view of their design rationale.

and the antenna has a low R and a C in the 100's of ohms.

This is the sad (and useful) fate of short antennas, yes.

So I don't know, is that () ? The question is retorical in nature.

It is usually rhetorical, yes, insofar as not being enumerated. Often
in technology it is a shorthand for a 10:1 ratio. Perhaps 100:1.

And what is this Xc(parallel) and Xc(series) stuff?

I took a little liberty there, The article had a schematic diagram showing
a series RC, then the radio showing the Parallel equivalent antenna
connected.
The the actual labels were Xs, Xp, Rs, and Rp.
Sorry if I muddied it, the attempt was to make it clearer.

I could follow Xc(parallel/series) easily enough, but what you
neglected to mention was there are two schematics embodied in the
single one you brought to the discussion.

Making questions simpler often leads to Byzantine answers.

Another problem in this simplification is that there is more than one
agenda being served, and they sometimes conflict with any single
solution. As often happens, when I ask "What do you really want?" I
get a response, I offer a solution, and I am immediately rebuffed that
it does not serve the other agenda - which, then leads me to ask "What
do you really want?"

73's
Richard Clark, KB7QHC