Ed,
Since you have already run the lines and probably cut them to some
preferred length, you may not want to do this. But for what it's
worth I don't bother with the matching sections any more. If you cut
the line to a multiple of a half wavelength (which must be done
experimentally unless you have access to some fancy test equipment)
it will repeat the impedance of the load. 50 ohm antenna, CATV line
cut to a multiple of a half wavelength = 50 ohms at the shack end of
the line.
73,
Paul N1BUG
Ed Stallman wrote:
> Hello Group, I ran two length of 3/4 inch 75 ohm CATV cable 200 foot each
> to my newly installed tower. one each for 6 and 2M ! What I'm looking for
> is an impedance transformer to match my radio/antenna, I believe a 62 ohm
> transformer. I remember seeing these somewhere made from copper water pipe,
> I think they were 1/4 WL? I've searched on the internet with no luck! can
> someone point me in the right direction with a URL or publication, ARRL VHF
> book. even the formula would be helpful for knowing the outside and inside
> diameter of the tubing.
>
> Thanks Ed N5BLZ
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