Topband: Inverted L
k9ay at k9ay.com
Wed Feb 6 09:49:06 EST 2008
from Ron, 4S7RO:
> Any recommendations re adding 80m to an existing 160m inverted L? Would it
> be better to:
> 1) insert a coax trap
> 2) Tue the antenna at the base (LC network)?
It is possible to install a separate 80M 1/4-wave wire at the same feedpoint
to make a "parallel" or "fan" vertical. To make it work properly, the two
wires should be separated by at least 24 to 30 inches (60-75 cm). It also
helps if both are configured as an inverted-L, with the 80M top wire pulled
away in a different direction. With these construction techniques, coupling
between the wires is reduced -- otherwise, you will likely have trouble with
80M matching and bandwidth.
I've done this myself in the past, and for a couple DXpedition antennas. I
think VK6VZ has a similar 2-band setup.
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