[Antennas] inverted L

[Igor Sokolov]

The length of the 160m leg depends upon the characteristics of the trap. In
case of coax trap (there can be also at least two variants)      the 160m
leg is around 12m long. It can be accuratly modelled if we know the length
of the vertical and the detailed construction of the trap (type of cable,
number of turnes and diameter, the way inner and outer conductors are
connected to the antenna).

73, Igor UA9CDC



> Hello,
>
> Well I found the problem with the 160M resonance.  I believed ON4UN's
book,
> and
> it clearly has wrong info in it.
>
> I adjusted the 160M leg after the trap by a whopping 20 feet, and got it
in
> range.
> ON4UN said 83 feet after the trap, and it is more like 63 feet.
>
> I rechecked the 80M resonance, and it did not change at all, which is what
I
> expected.
>
> Both antennas have poor bandwidth.  Since this is my first inverted L,
> perhaps this is
> the way they are.
>
>
> So, my initial problem is with the trap I believe, and I can work on the
> ground system
> later.  From what I read, I can add radials up to 64 to improve the
antennas
> performance.
> After 16 radials, it seems that the match will not change much, so if I
> discover what this
> resonance problem is, then adding radials should not alter the match.
>
> 73's
>
> Glen K4KV
>
>
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