Inverted L does not necessarily need a cap (a reactance) to work and to be
properly matched.
It may be matched with a capacitor with when its feed-point is looking reactive
(inductively), as well as it may happen with any other antenna.
If the inverted L is not quarter wave resonant, but longer, its impedance looks
higher, and inductive.
At a certain lenght, and taking into account also ground losses, feed point
impedance can be something like 50 ? J. Putting in series a capacitor whose
reactance is +J the SWR goes 1:1.
Moreover, if the capacitor is variable some adjustment is possible when the
operating frequency is changed.
Note anyway that the higher impedance has nothing to do with efficiency while
inverted L length may change substantially radiation patterns, as well as the
energy radiated in the H and E planes.
If what you want is a medium and long distance antenna, an improvement over
your dipole, I don?t suggest the inverted L is above a ¼ electrical in length.
73,
Mauri I4JMY
> Well the snow is finally starting to fly here in Wisconsin so it is time to
> put up a 160 antenna.I have used an inteverted v here for years with the
> apex at 70 feet and the ends at maybe 30 feet,pretty poor.......I would like
> to try an inverted L.It is my understanding that they need a cap. to tune
> them into the freq that you want.I have an 80,70 and 2 60 foot towers to use
> as supports,and lots of room for radials.Are L's directional?What would be a
> good starting point in length for say 1.85 mhz.Are they broadbanded?Any
> ideas???? Gregg K9KL
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