There is some confusion on the W9INN antennas. The antenna labeled
"Broadband" has two flavors.
There is a 160/80 version and a 160/80/40 version. This antenna does not
require a tower to complete
the sloper. Actually it can be mounted as a dual sloper or as a L. I had
one up (wind storm took it down) as an L with 78 feet vertical and 27 feet
The antenna (160/80) is actually two 1/4 verticals with the coil acting as a
trap to cut off 80 and shorten the 160 to a total length of 105 feet. The
W9INN catalog gives a fukll page to this antenna. With PROPER ground and
several radials it works well and covers 80 to 90Khz on 160 and 120 to
130Khz on 80.
It beats most of the slopers on the market but does not equal a 1/4 vertical
or 3/8 wave L. However the 160 can be made into a 3/8 wave L by adding
about 40 feet after the coil. The 3/8 L lifts the main radiation near the
top of the antenna from near the ground plus more closely matches 50 ohms.