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Old September 9th 04, 02:47 AM
Jack Painter
 
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Hi Steve, lol at the [OT] comment, I suppose that's true sometimes..

Since we are a shortwave group, at those frequencies 50' of anything will be
fine with little if any noticeable difference between feedline choices.
Shortwave listening requires the best signal to noise ratio, with little
effect from minor attenuation of cable loss. Scanner listening, especially
above 225mhz, requires maximum signal possible, with little if any concern
for SNR. Height of the antenna is important to both shortwave and scanner
frequency listening, so your friend is wrong about the loss v. height issue.
The principle of diminishing returns applies to heights over 100' unless you
can afford heavy hardline for scanner frequencies.

Jack

"Steve" wrote in message
om...
This is off topic, but I'm going to ask it anyway...

I'm don't have a lot of technical expertise and I'm wondering how one
determines what kind of coax to use as a feedline. I currently have
about 50 feet of fairly thin (RG174) coax that I'm using to feed an
outdoor active antenna that's mounted on the fire escape outside my
window. I'm thinking about mounting the antenna on the roof of my
apartment building and suspect 50 ft of feed line might just be enough
to allow me to do that. However, a friend of mine told me that 50 ft
of RG174 is going to allow too much signal loss. So, there you have my
first question: Is 50 ft of RG174 coax a bad feedline?

The second question is this. My friend seemed to think that the 50 ft
run to my roof would result in greater signal loss than the much
shorter run to my fire escape, even though we're talking about 50 ft
of coax either way. This didn't make sense to me. 50 ft of coax is 50
ft of coax, it seems to me, whether it's coiled and leading just
outside my window or straight and leading all the way up to the roof.
Am I wrong about this?

Steve