I submit the following as "general rules" I have observed in working
with stacked yagis. To be sure, there are exceptions and no one antenna
is BEST. The following assume properly installed, tuned, phased, spaced
etc... :
1) the stack generally does better than the 3DB calculated gain
2) the stack is best if selectable U/L/Both
3) the Both position is usually the best and most rarely less than
either of the other combinations
4) the Upper is 2nd in signal strength
5) the Lower is 3rd and RARELY best ( but it does happen- thats why u
have the swtitch position)
6) swr of a properly phased stack is lowest when in the same direction
and highest when 180 deg. apart
7) during times of heavy precipitation static the Lower antenna may be
perfectly quiet
8) multiple stacks are even better; my 4/4/4/4 on 15m is the best
antenna I have followed by the 4/4/4 on 20M
These are a few of the "facts" I have observed while playing in the
yard. The best one though is no antenna is ever high enough! ( At
least I have never had it too high here--- but my tower only goes to
200 ft)
Have fun guys.... Playing with antennas is better than making contacts!
73,bud
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