In 1998 I added significantly to my 10M antenna choices. Currently I have
the following choices...
1) 5/5 (105CA) at 50' over 25' rotating
2) 7el on 34' boom at 120'
3) 7el on 34' boom at 37'
4) 8/8 on 48' booms fixed to EU at 42' over 18'
The 8/8 was the big addition before CQWW SSB in the fall. The stack is
optimized for F/B and bandwidth. In the fall I noticed that the 8/8 was
much quieter than any of the other antennas (much better pattern). But
when listening on a QRM free frequency, it seemed that it was no better
than any of the other antennas. It was difficult to hear the difference
between any of them except for the one at 120' (which as usually down from
the others).
Well this weekend in WPX, the 8/8 really shined. There were MANY stations
that were inaudible on any other antenna, but perfectly copiable on the
8/8 stack. This on a very clear frequency, where QRM was not an issue.
I'll also throw in another note from ARRL DX CW, where the 7 element yagi
at 120' was much better than the 5/5 or the low 7 element to JA due to
band noise. Both the 5/5 and the low 7 (both antennas having
about the same average height) produced "crud" at about S-5 to S-7 levels.
Switching to the high antenna completely eliminated this noise. A big
difference.
My station is on a hilltop with a fairly drastic slope in front of all
these antennas. The heights I used, would probably not be applicable to
someone on flat ground. All antennas were optimized in YO and AO and
analyzed using TA and YT.
Hope this is of interest to someone.
73
Bill, W4AN
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