On 7/18/02 11:31, Jimmy Weierich at kg2au@stny.rr.com wrote:
>Shrug off the myths embraced by the mediocre. Don't listen to people who
>tell you that 2:1 SWR is good enough because all the power goes somewhere
>eventually.
*IF* feedlines were lossless, this would be true. In some situations, one
can use a feedline that is nearly lossless, so that the absolute SWR
matters less.
Such antennas are usually compromise antennas, and contestors are less
likely to compromise. Even so, LB Cebik's 88 foot doublet design is a
compromise of this type. It was really intended as a backup or second
radio antenna.
>Or that 9913 is lossless at HF.
9913 isn't lossless at HF, but it's loss is lower than other coax. Well,
that is, until it fills up with water....
>Or that a 1 dB difference in a signal is unnoticable at either end.
For signals well above the noise, 1 dBis just perceptable. But for
signals in the noise, it cam make all the difference.
>Or that connector loss is negligable.
If connector loss were even 1%, running 1500 watts through a connection
for just a few minutes would heat it up with 15 watts of power. They
would be HOT.
In practice, when properly installed, connectors do not heat this way. In
fact, even at full power, most connectors don't show any measurable
heating at all. This lack of heating indicates that connectors have
negligable loss.
That said, you're still better off to have as few connectors as you can.
Each connector is still a point of failure.
>All those statements are lies. Find out why.
Not all of them are lies. But finding out why is good advice....
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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