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Old March 23rd 04, 09:34 PM
Jack Twilley
 
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"Richard" == Richard Clark writes:


Richard On Tue, 23 Mar 2004 00:29:43 -0800, Jack Twilley
Richard wrote:
Yes, but pursuing a match close to 1:1 and an impedance close to 50
ohms seems to be a reasonable pursuit, if I understand correctly.


Richard Hi Jack,

Richard This is an aspiration on par with monks seeking nirvana. The
Richard two illustrate it is the path, not the destination that is
Richard meaningful.

Richard There is a very clear point to be made that unless you
Richard elevate the dipole, any 50 Ohm characteristic you observe
Richard will more ground loss than radiation resistance. This is
Richard reasonable only in the sense of ease of tuning and the
Richard reductio ad absurdum is bliss can be found in a dummy load.

Oh, I see your point here. What you're saying is that my dipole is so
far from the ideal that reaching 50 ohms won't mean anywhere near the
same thing that it does to the ideal case. That begs the question,
then -- if not 50 ohms, what is the best value for my particular
configuration?

Richard Clipping the ends of the current structure do not lead to
Richard increased benefit unless you shave your advantage in tenths
Richard of a dB. To put that in perspective, unless you are a
Richard teenager, you and your contacts couldn't possible hear any
Richard change below 1dB variation. To force that perspective
Richard further, propagation variation through one QSO easily varies
Richard by that much or more (unless we are talking line of sight FM
Richard with full quieting).

I've listened to QSOs where they've ebbed down to the noise floor and
flooded back several times over the course of a minute, so I
understand what you're saying.

Richard 73's Richard Clark, KB7QHC

I am really interested in knowing what sort of target values would
represent an optimal configuration, if that's at all possible.

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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