Hi Russell,
You wrote:
"I plan to put up an Inverted-L for 160. Do I need a balum? Can I feed
it with ladder line? Is the longer the better or should I stick to +/-
170 feet."
==========
No, you don't need a balun. Feed it with 50-ohm coax, center conductor
to the bottom of the antenna wire and shield to your ground system (as
with all antennas of this type, it requires a good ground radial system
to be really efficient).
Make the vertical portion as high as possible, with the horizontal
portion long enough to make the antenna 1/4-wave resonant at the
frequency of your choice. A total wire length of about 140 feet is a
good place to start, then prune the length for lowest SWR at the
frequency of interest.
If you have a variable capacitor (about 0-250 pF) that will handle the
power level you plan to run, make the antenna longer (about 170 feet) and
connect the capacitor in series with the wire at the feedpoint and use it
to tune out the inductive reactance (i.e., for minimum SWR). This will
give a closer match to the 50-ohm feedline and allow you to QSY over the
entire band (by retuning the capacitor, if desired).
73, de Earl, K6SE
___________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
or call Juno at (800) 654-JUNO [654-5866]
--
FAQ on WWW: http://www.contesting.com/topband.html
Submissions: topband@contesting.com
Administrative requests: topband-REQUEST@contesting.com
Problems: owner-topband@contesting.com
|