I wrote:
>If you look at a model of a stack,
the pattern is fairly insensitive to slight differences in phase.
I recall seeing little difference for ~10 degree phase difference,
which is far more error than you would get by simply cutting
lines to the same physical lengths, even on 6 meters.
I did a quick check of this using an old (pre-YO7)
Eznec model when I was modeling a stack of my KLM 610's.
This is for a two antenna stack, as you will have on 6m.
I used 1 wavelength spacing:
Phasing Gain (over flat terrain)
In-phase 16.85 dBi (all at 8 degrees TOA)
Bot +10 16.83 dBi
Top +10 16.81 dBi
Assuming Vf of 0.8 for your coax, 10 degrees equates to
5.25" difference in coax length at 50 MHz. Since you
can probably cut your coax closer than that I wouldn't
bother with tuning it, although I would still check with
the MFJ just to be sure there are no problems.
73, Bill W4ZV
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