Thanks for all the comments on my request re stacking. I have made further
checks using Eznec and I have found the following. With a 4el 10m lowest in
the stack with a 15m above it and both in line, the gain of the 10m 4el not
necessarily F/B is reduced with all the separations I checked, that is from
7ft to16ft.
At 7ft the gain is 2.62 db down on the 10m yagi measured on its own or with
it turned 90 deg' to the 15m. With both antennas at 90 deg' there is no drop
in gain with any separation calculated. With the two antennas in line and
separated by even 16ft there is a gain drop of 0.72 db. At a distance of
what one might think of as reasonable ie 10ft the gain on 10m is down 1.83
db. I repeat that the patterns appear reasonable but the max gain is down. I
suspect there are many stations out there thinking there antennas are
working well ie F/B but the gain is down by the equivalent to a 2nd yagi
phased. Is there anyone that has confirmed my results?. By the way I used CC
4el designs for the yagis.
My thought is that the problem lies with the forward D2 on the 15m absorbing
10m RF. any comments. 73 Clive GM3POI
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