Why is an inverted "L" apparently so popular on 160 when it wastes so
much RF as a cloud warmer? It is so easy converting an inverted "L"
into a Marconi T. The flat top can be 130 feet fed exactly in the
center by a single drop wire to the ground with the appropriate
network. A 65 foot drop wire comes very close to 50 ohms and any
reactance can be removed with a series capacitor. Apart for the
cancellation of high angle radiation this configuration is some distance
away from support structures. So many try to configure an inverted L by
using their metal towers as supports for the fed end. This sometimes
means you are just shock exciting the metal tower and your feed
impedance results may be all over the ball park.
I challenge anyone to find a situation where an Inverted "L" will
outperform a properly configured Marconi "T" with an ample ground system
on either.
Herb Schoenbohm, KV4FZ
On 8/11/2013 5:48 PM, Don Johnson wrote:
I have not seen a length mentioned for the inverted L, so thought I would note
that by making the inverted L longer than a quarter wave moves the high current
portion up the vertical. I had good luck with an inverted L about 3/8 wave
long. By good luck I mean DXCC plus some on 160. I still am trying to improve.
In any event feeding the inverted L with a series capacitor made tuning a
breeze. By going longer than a quarter wave made the feed point inductive and
raised the R value closer to 50.
73,
Don
N4DJ
Sent from my iPhone
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