I had meant to send this out to everyone and not just Steve.
At 01:43 PM 10/27/2005 -0700, you wrote:
>Hi, I am wondering what the stacking distance should be for a 5 element
>50mHz beam, 13 element 144mHz beam, a 21 element 432mHz beam, and a
>144/440 dual band beam (5 elements each band). I want to stack them in the
>above order from bottom to top (50,144,432, dual). I am hoping it isnt TOO
>far hehehe.
>
>Steve, KC8QVO
>
>
Steve,
I think you will do ok if you ensure the lower freq antenna is at least 1/2
wl from the one you are looking at. I believe 1/2 wl is the minimum
distance. This was the minimum spacing back in 1970 and I don't think the
recommendation has changed much. I used this rule when putting up my 7
beams on my tower and they all work fine. Not the best but certainly workable.
Keep in mind, the 6m antenna looks like a ground plane to the 2m
antenna. Both the 6m and 2m antennas look like a ground plane to the 70cm
antenna.
Ie the 2m antenna should be 1 meter away from the 6m antenna and the 70cm
antenna should be at least 35cm away from either the 2m or 6m antenna.
If you put the 6m on bottom, 2m on top and the 70cm in the middle, with a
minimum of 3' away from each other, you should not have any major problems.
You will have a problem with the 2m/70cm dual band unless you orient it
vertically (I am assuming you are referring to an FM beam which is end
mounted) in which case, there should be no effect between the two 2m beams
so space it mechanically sound above the 2m beam.
Lee Scott - AA1YN http://www.aa1yn.com
Home of the VHF & Up Register http://www.aa1yn.com/vhf
Home of the VHF Talk chatroom http://vhftalk.aa1yn.com
Hooksett, NH
FN43gc52
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