On Sun, 21 Sep 1997 11:52:21 -0600 Larry Menzel <lmenzel@millcomm.com>
writes:
SNIP
>Will RG58 suffice for the run from the switch to the shack...about 150
>feet, or should I use a lower loss coax?
RG-58 is fine for that short run; the loss is only about .75dB on 160 and
1.5dB on 80. The band noise will easily mask the loss.
One thing to watch for with any regular type coax is rodents. At least in
New England they like to nibble on the jacket allowing water to get in.
Try and run it up in the tree branches if possible.
Check the cable loss at the highest frequency you plan to use before
bringing outside...if it is ancient stuff that has spent many years
outside it may be pretty lossy. Also do not use cheap Rat Shack or
similar cables with marginal shielding. One way to test shielding
effectivity is to stretch it out, terminate the far end in 50 Ohms and
tune in a BC station. The difference between that signal level and when
hooked to the antenna should be about 80dB or better. RG-6 Quad Shield
or Hardline is in the 100+ dB range. The bottom line is that you do not
want the feedline picking up any noise or IM causing crud, particularly
if the feedline goes near a tower, TX antenna, TV antenna/ CATV drop or
AC power lines.
After the mice made a mess of my single braid, non-flooded RG-6 I
replaced the 700' feedline with some .412" CATV hardline. It became
immediately apparent that the virtually total shielding reduced TV set
and computer crud here to new lows.
73 Carl KM1H
>
>Thanks in advance, and looking forward to the coming season of topband
>dxing.
>
>Larry N0XB
>Northfield, MN
>
> -
> ---
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>
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