[VHFcontesting] impedance transformer

[Paul N1BUG]

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