At 03:08 PM 5/13/2005, Gene Bigham wrote:
>So could I ask the question again, as I am not sure I have gotten my
>answer yet.
>
>"What is the difference in perception at the receive end of a HF wireless
>signal transmitted with an antenna measured that has a 2:1 (impedance
>either high or low) SWR versus an antenna that has a measured SWR of 1:1.2
>or so - given you are working with the same antenna AND given your modern
>rig does not power reduce prior to 2:1 SWR?"
>
>What will the other station perceive? Show your work please.
>
>The key here is what is perceived at the other end of the transmission
>circuit versus the time and effort to improve an antenna from 2:1 to 1.2:1?
>
>So far there have seen two dissimilar responses and a lot in-between:
>
>With 1.2:1, the return loss is 26.4 dB: only 2.2 Watts gets reflected back.
>(0.01 dB decrease).
>
>Hmmmm 1.2:1 lead to 26.4 db loss? That does not sound correct.
Return loss is a term for the ratio of reflected power to incident power
(the reflected power is -26.4 dB less than the incident power). The actual
through loss is hundredths of dB.
>To...
>
>Assuming the SWR is correct, you will lose 4% of the power
>transmitted. Say 40 watts at one KW out.
>
>I am working on my own answer to the question showing formulas, and etc.
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