Denny, I must disagree with you based strictly on experience. Others, please
forgive me repeating myself from an earlier message. I have six stacked triband
yagis on a 190 ft. rotating tower. It works well enough that I can often get a
major European pile-up going anytime there is propagation. Over the years I
have
made a habit of asking stations that I hear in the pileup who are 10 or 20 dB
above the crowd what antenna they are using. Invariably, the the response is
either a stack or a quad!!!! Also, I have a stack switch that allows me to
check
signal strengths of any combination of pairs of antennas. After playing around
with the switch for the first six months or so, now I just leave all antennas
switched in at all times. The whole stack is almost always (at least 85% of the
time) better than any other lesser combination. I am enough of a believer in
stacks that I use them for the tribands, 40 and six meters and none are a
disappointment considering the added expense and effort.
73/Mike, N7ML
CQK8DO@aol.com wrote:
> Josh, each time you double the number of antennas in an array you get a
> maximum of 2 + a fraction dB.... The very best you are going to see with a 4
> stack is 9 + - dB (roughly)... And secondly, on hf the lower members of the
> stack add less to the overall gain than the higher members, plus you have the
> phasing harness losses, and you have the major impedence changes if you are
> trying to switch parts of the stack in and out, which requires sevick style
> transformers, relays, etc... (spelled $$)
> In my non humble, and egotistical opinion (IMNHAEO), you have two far, far
> better options for the money
> 1. To raise the tower by 30, or more, feet and go with a 2 X stack....
> 2. To raise the tower by 60 feet, or more, and go with one antenna...
>
> Cheers ... Denny
>
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