A quick check with EZNEC shows the following loss in the 30 feet of
RG213. The antenna was placed at 40 feet.
3.5 MHz 2.17 dB
7 MHz 1.95 dB
10.1 MHz 4.42 dB
14 MHz 6.5 dB
18.1 MHz 2.28 dB
21 MHz 3.1 dB
24.9 MHz 4.35 dB
28 MHz 3.12 dB
I didn't try to find a better solution, but different lengths of 450 ohm
line will produce a different set of answers and some lengths will
probably produce a set of numbers that is better than the one above.
>After some serious tree trimming, I now have room to fit a full sized wire
>antenna where my G5RV is right now. I am thinking about a 135' open wire fed
>dipole, as multi bands are needed.
>Question is this- there is now way I can get 450 ohm feedline into the
>shack. The best I can do is about 30' of RG213, then the rest 450 ohm (
>90'). Is this going to be a waste of my time, or is it worth it? I'd
>use a balun to change over to 50 ohm feedline.
>73- Chuck KI9A
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