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Old January 9th 05, 05:18 AM
Dale Parfitt
 
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Jeff

Averages are perhaps meaningful if the process is linear- however,

attenuation vs freq is not linear and that is why one does not speak of

loss
averages- you won't find it in the literature.
2nd- 1mhz is millihertz= 0.001 Hz. You likely mean MHz.

Dale W4OP

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Hi Dale,, at least its nice to read someones post that makes

sense. And
yes I realize that "averages" do not directly apply to rf attenuation per

coax.
My point was, no one parks there scanner on .9-1 Ghz. and leaves it there.

Most
people usually listen to where 90% of the action is and that is usually

between
100-500Mhz. Given worst case scenario at 1Ghz the difference between
9913 and RG 6 is -1.6db/100'. I believe the original poster said his run

was
less than 50',, which would put cable loss at around -.8db between the 2.
Given the capture affect of FM transmissions a -.8db isnt going to mean

the
difference of hearing or not hearing a signal. And yes I meant Mhz not

mhz,
a typo. My whole point was there is "very" little if any noticeable

difference
between using RG 6 and 9913 for general scanning purposes, and its a whole
lot easier to work with.


Jeff

I agree Jeff,

And the difference between 75 Ohm and 50 Ohm is inconsequential given that
the scanner front end certainly does not look like 50 Ohms all across its
ranges.
There are some very good F-56 connectors out there with integral O rings
guaranteeing a nice watertight seal if also used with coax-seal or the like.

73,

Dale W4OP