- Thread starter Blkops
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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?

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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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.kb2vxa said:Danny, your math is a bit off. The decibel scale is logarithmic, not linear.

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.

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