Thanks for starting this thread...antenna subjects wake me up!
But first, for those of us who love baseball, have you ever noticed how
easy some guys make the game look? I could read tons of books, practice
until I dropped and still never
make the plays that the worst pros make... how easy Ken Griffey makes it
look to hit a 100mph fast ball---- what a smile as he watches it sail over
400 ft!!!
Junior probably never read the books....
I mention the baseball because antenna stacks are much the same... lots of
books, lots of math and theory but yet-- very simple! ( See the ball-- Hit
the ball).
So for those considering a stack do some research, study all the facts but
keep one thing in mind--- it probably will work better than you thought it
would--- even if it isnt perfect! ( Junior simply doesn't get good wood on
every HR).
Whether you use 1/4 wave 75 ohm cable and a T or a Stackmatch; whether
you use odd multiples of 1/4 waves; whether you space them 1/2 wave, 3/4
wave or
1.5 wavelengths ----- they simply will work. ( And work better than the
single antenna that you were using!) Do it right but KEEP IT SIMPLE.
Can you stack dissimilar antennas? In a word YES! My 40m stack consists
of a home brew 3 element on a 48 ft boom ( full sized elements ) at 160 ft;
bottom antenna is a KLM 40M-4 at 70 ft. Both antennas rotate and may be
selected
both/upper/lower. The Both position is almost always the best, upper only
second followed by the lower.... A great advantage in contests is to set
the lower on the Carib. and the upper on Eu. or Asia and use the switch.
For the multiplier or the DXCC new one point them both in the same
direction and see how much better the stack works!
Will a pair of dissimilar antennas be as good as an exact matching pair---
probably not... but remember we live in the real world and not everyone as
two of everything.
I have enjoyed playing with stacks for over 25 years.... my worst stack was
still better than the antenna it replaced. I now have 10 different stacks
on 10-40( the 40m stack is the only dissimilar one). So the advice from me
is follow the basic theory and keep it simple. Dont break the rules but
dont be confined by them either.
See the ball- Hit the ball.
73 ( and enjoy the antenna work)
Bud- k4isv
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