Coax Cable

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Blkops

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Mar 19, 2008
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What is the best cable you can get for an outdoor antenna, the antenna base is about 6 feet away from the scanner. I've looked around and it seems like a lot of people like LMR400, what about LMR 600? Thanks for the help
 

n4yek

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At 6 feet, it won't matter to much about the coax.
LMR 400 is good for higher freqs because of it's low loss factors, but at 6 feet pretty much any 50 ohm cable will do.
Coax loss is rated at 100 feet lengths.
Example: (in theory of coarse)(also depends on the frequency the loss is calculated for)
coax loss at 100 feet = 6db
at 50 feet it would be 3db
at 25 feet it would be 1.5db
at 12 feet it would be 0.75 db
at 6 feet it would be 0.375db
see what I mean?
 
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zz0468

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kb2vxa said:
Danny, your math is a bit off. The decibel scale is logarithmic, not linear.
No, his math is correct. The db scale is logarithmic in terms of power ratios. But a 6 db cable cut in half would have 3 db loss per each half.

Here. Go play with this:

http://www.ocarc.ca/coax.htm

For convenience sake, use LMR400, at 2004.5 MHz. It works out to be 6 db loss for 100 feet. See for yourself.
 

K4DHR

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I just use mini 8 for my short runs, since it is usually better shielded than RG-58. It is just slightly larger, only a few cents more a foot and is just as flexible.
 
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