Topband: 160m int L

[i4jmy at iol.it]

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