I am currently installing Six m2 432-9wl, and 4 - K5GW-10 yagis (quite
similar to
m2 12 ele. I was originally going to do exactly as you proposed, (with 4
432 instead of six). After *lengthy* conversations with Mike Stahl &
Gerald Williamson, both
gentlemen thoroughly convinced me not to stack box style.
1. 432 pattern on the 9wls will be destroyed.
2. 144 array will be degraded.
3. 432 beam width too tight for terestrial (sat too ?) vs vertical
stacking.
They convinced me to stack vertical on both bands (ie - 4 high)
one band on each side of frame(Yes - 30 to 32' riser). Put 144 on side one,
& 432 on side two with 1296 above or below 432.
your choice of az/el is certainly adequate.
Bert - NS4W
At 06:50 PM 3/3/98 -0500, Roger Rehr wrote:
>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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