In a message dated 9/6/01 10:11:08 PM Pacific Daylight Time, poster@gate.net
writes:
<<
I'm just wondering how they compare in performance??????
Jack
>>
I presume you are interested in comparisons with current 80/75/40M verticals.
The present ones weren't around when I used the HT-18 Hy tower. It did very
well for me on 75&40M and I based loaded it to 160M. I had to raise the Z as
it was about 20 ohms or so. I added a Xc across the feed point of such value
with it resonated lower that it gave 50 ohms. It worked well but it had
narrow bandwidth.
I then modified it top loading it to a 1/4 wave on 160M. On 80/75 it was
then a 1/2 wave electrically and a 1/4 wave physically which was matched with
an L network. On 40M it was a 1 WL on 40M electrically and 1/2 wave
physically and matched with an L network. It worked far better this way on
all three bands. The Z was higher but still not 50 ohms and I used the Shunt
Xc again. The details are in a CQ article I wrote about 35 years ago. I
have 2 other versions (Mark II & Mark III) now. k7gco
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