Thread: First Attempt
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Old March 18th 06, 08:21 PM posted to rec.radio.amateur.antenna
Owen Duffy
 
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Default First Attempt

On Sat, 18 Mar 2006 10:21:27 -0500, "Basil Burgess"
wrote:

Hello all

I've made a first attempt at installing an antenna. It's a 2 Slinky dipole
strung across my roof. I chose the Slinky dipole because it promised to give
good (if not excellent) results in a relatively short antenna. I strung it


There is nothing in your post to indicate how long or short your
antenna is. Perhaps it is a well known design and I just haven't heard
of it in my limited experience.

You say how difficult the coax was to match with an ATU, that is a big
hint that the coax is operating at high VSWR. You say the SWR was
terrible, what does that mean, do you have the numbers? Coax operated
at high VSWR for significant length is quite lossy.

If the impedance presented to the tuner is extreme, you can expect
excessive losses there too.

The ambient noise on low HF bands is very high compared to the noise
floor in your receiver. An antenna system could be seriously lossy,
and yet still allow you to hear all signals above the noise (though at
reduced S meter deflection). Beware of depending on a simplified
receiver test to infer transmit performance.

Owen
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