I can't speak to verticals spaced that tightly but I can speak to dipoles
spaced that tightly. I have 2 phased half wave dipoles spaced 1/8 apart and
fed 180 degs out of phase. I get nice gain (looks like a solid S unit or
~5db as expected from on the air tests). But the bandwidth has to be
managed. The 2:1 BW is no more than 125khz. No issue on CW when I use my
CW stub setting but a definite issue going from 3850 down to 3600 in an SSB
contest.
And additionally, the impedance is very difficult to match. I have used
open wire line feeders and found the 50 Ohm matching point to tap off - I
believe about 3/8 wave down the feed line for each element. The impedance
changes significantly as you shift frequency.
I have opted to use a remote tuner at the connection point of the 2 feeders
to get full band SSB coverage which works slick.
The verticals will present different impedances than the dipoles, but I
would think the complexity of the 1/8 wave separation and phasing would be a
similar bronco to ride.
By the way it's a "kick @#s" antenna to EU. I often get "loudest USA
station" reports when running in a SSB DX contest.
73
Ed N1UR
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