Topband: losses on beverages

[John Kaufmann]

At 04:59 PM 10/16/99 +0200, DF2PY wrote:
>What can be learned from it,is that even rx antennas need be matched 
>perfectly.If i had not had the choice of different bevs of equal length i 
>would 
>never have learned about this serious degradation in performance of
>beverages.

I have found exactly the same thing with terminated Beverage antennas.  I
believe this can at least partly be explained by the fact that a mismatch
at the receiving end of the Beverage causes a partial reflection of signal
current back down the Beverage toward the terminated end.  Most of this
reflected energy never reappears at the receiving end.  Part of the
reflected signal is dissipated in the Beverage wire itself as it travels
back down the wire.  Most of the rest of the energy is dissipated in the
terminating resistor and is forever lost.  This loss mechanism does not
generally apply to conventional antennas which don't have resistive
terminations.

73, John W1FV


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