I am posting this to get considered opinions re: how to position stacked
yagis for 144 MHz, 432 MHz, and 1296 MHz, to be used for satellite work (I
have become convinced that a high gain linear array is superior to circular
pol for this purpose in the absence of polarity reversal capability), for
EME, and for terrestrial weak signal work.
I have limited real estate in that for zoning reasons my antenna tower must
be located fairly close to my house (about 11 feet from it). This limits
the size of the installation. I also need to make the installation as
compact as I can for aesthetic reasons because of my neighborhood. I am
putting up a US Towers HDX572MDPL.
I want to have:
4 M2 12 el yagi stacked for 144 MHz
4 M2 9 Lambda yagi stacked for 432 MHz
4 M2 35 el yagi stacked for 1296 MHz
1 Myers 3 x 2 slotted dish for 2400 MHz.
I have been told that I could stack the 144 Mhz yagis in a 2 x 2 array
approx 10 feet on a side,
and then stack the 432 MHz antennas nested within that rectangle(70 inches
on a side), and then stack the 1296 antennas within the 432 stack (28 inches
on a side). The dish would go "somewhere" (not sure yet where).
It seems to me that the nesting would disrupt the interactions that lead to
the increase in gain seen with stacking, and another source has told me that
in fact such nesting will NOT work (not to mention the desense potential for
mode JA satellite work).
Before I spend the bucks and put this together I'd like to get some truly
expert opinions. I suspect though that nesting stacks is a case of trying
to get "something for nothing", and that never has worked in my experience
in other endeavors.
While you're at it, is the choice of the M2 OR-2800 for AZ and M2 MT-3000
for EL my best choice for rotators?
Please help! The check for the tower is in the mail but the remainder of
the project is on hold pending resolution of the above.
I do not generally cross-post but have asked this of the MGEF, of the VHF
net, Towertalk, and MOON-NET to get opinions from several groups with
potentially different perspectives (and different areas of expertise). If
anyone wants a summary of the results, let me know and I'll mail one. IF
there is a lot of interest in these I will repost where appropriate.
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