In a message dated 97-09-30 15:53:04 EDT, aa4lr@radio.org writes:
<< Even better would be open wire line, if you could find it. Radio Shack
used to carry this stuff about 20 years ago for use with television
antennas, but no more. Or you can make your own. >>
I've been making my own feedline for the last year and am quite satisfied
with the results. I make my own spacers by cutting up plastic hangers
available at WalMart (usually 10 for 88 cents). This plastic is very light,
but has very good dielectric properties and seems to weather well. I've used
spacer widths from about 2" to 5". I groove the ends by cutting a 1/4" cut
with a hack saw blade and inserting the wire into the slot. I use heavy
nylon fishing line as a "hanger", using a 10" diameter loop and slipping it
over the ends of an insulator and suspending the line from tree branches or
eaves.
Very good results. I've used the Autek Research RF-1 recommended method for
determining feedline losses, and they are negligible at 30 MHz. Also, there
is almost no change is tuner settings when the feedline gets wet.
The left over hook on the hanger has been used to hang an inverted V from a
tree branch.
Glad to share any further details. 73, Paul, KB8N
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