On Mon, 26 Sep 2005 00:29:55 GMT, Rockinghorse Winner
wrote:

Ham op writes:


My installation is as follows: 1) 600 ohm open wire line [tuned of
course!] from the antenna to a protected [from WX] area under the sun
porch. There I simply connected 450 ohm ladder line to the 600 ohm line
for the run into the house. [450 ohm line has increased losses in bad
WX]. As mentioned in another response, I run the 450 ohm line at right
angles over metal structures. I keep the line a least 6 inches from
pipes, heating vents etc and twist the line one twist every three [+/-]
feet.

I run 1 KW 80 through 20 meters with NO interference or RFI in the
shack. This computer is located 3 feet from the amplifier and has no
adverse effects from the amplifier. BTW, my station is grounded
[earthed] IAW electrical code.

Are there any lengths for the xmission line one should avoid when feeding
different types of wire antenna?

Some lengths work better than others, depending on band. See the web
site, http://www.qsl.net/w5dxp and look at the "tunerless" all band
antenna fed w/ladderline.

bob
k5qwg