My preferred method is to use multiples of 1/2 WL on 80M,
but then most of my long runs are 300 to 600 ft.
Answers to your questions are included below.
For less than 200 ft, some of the new low loss cables
are probably a better solution.
de Tom N4KG
On Wed, 07 Oct 1998 10:07:13 -0400 "Ted Boerkamp"
<Ted.Boerkamp.boerkamp@nt.com> writes:
>
>hello everyone....first, i wish to thank everyone who has responded to
>my earlier msg concerning the measuring/cutting of CATV cable....
>I guess at this point I have a choice to make....my dilema is that
>when
>i calculate the physical length of a run of CATV , the two numbers
>that
>i end up with are : 112 feet +/- and 224 feet +/- (dependant on VF of
>cable)...
>The distance i have to run this cable falls somewhere in-between at
>abt
>150ft....the four options i have (correct me please if i am wrong)
>are:
>1. cut for the longest length (good for .5 wl on 160m) and coil up the
>extra
> length at the house before it goes thru the wall.
This would work. Total loss on 10M approx 1.1 dB.
>2. cut for the shorter length (good for .5 wl on 80m) and make up rest
>with
> rg-213....(this will mean 40-50ft of rg-213...doesnt this defeat
>the
>purpose
> for using low-loss cable?? the ratio of CATV to rg-213 is 112 to
>38
>feet
> or 30% of my run will be higher loss cable....
This is also acceptable. Total loss on 10M also around 1.1 dB
>3. use matching transformers ....do you still need to cut CATV to
>resonant
> lengths when using these transformers???
I don't like matching transformers for high power but
I guess they do work. More expensive solution.
Cut the cable to the needed length.
Total loss at 10M is 0.75 dB plus 2 times the transformer loss.
>4. just cut the CATV to the length that gets me from "A to B" without
> checking for resonance.
Not a good choice unless you don't mind using an
antenna tuner where SWR is higher than desired.
>I guess I wish to ask everyone their opinion on what they think I
>should
>do
>in my case....have I listed all the possible options??? I am presently
>undecided
>as to what I should do.....thank you all again for your help....this
>is
>a great
>reflector for getting useful information.....take care and 73 Ted
>VE3SS
>
>
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>
>
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