Hi Jim,
I hope we haven't been confusing things with the so called tilted LPDA's.
LPDA design is quite different than Yagi design. Each element is split and
there are two hot booms placed in the same plane (parallel to each other).
One side of the split element connects to one boom and the complementary
one to the other boom and then alternated as you proceed down the boom. I'm
sure we are all familiar with that approach which is the common type of
LPDAs we use nowadays.
However, in the early days (1950 through 1960's) of LPDA design, some of
the first designs used hot booms were often placed with a 30-45 degree
angle between them (instead of parallel to each other). The elements were
still connected as above. However, as you proceed away form the feed point,
the matching complementary pairs were placed further apart. This gives the
appearance of stacking.
I hope the above is clear.
73,
Joe, W1JR
At 11:55 AM 3/20/2002 -0600, James H. Fitzpatrick wrote:
>I saw the tilted LPDAs near Champaign in August 1982 when I drove by while
>moving to California. I wondered then what it was all about. Now 20 yrs
>later I found out.It pays to subscribe to towertalk ;>)
>
>Jim
>
>WI9WI
>
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