I recieved many postings with comments, recommendations, and experience.
These ranged from antenna handbook advice to real-world examples. I am
going to answer all the people who sent me help- both on line and off, but
the answer seems to be that using the spacing I have, with booms lined up,
will probably work fine.
There were links to pics- one I have always liked was Dick Flanagans story
of putting up his tower, with antennas.
>I am using 12-foot spacing between the tribander (TH-11, actually) and
>the shorty forty (40-2CD), with the six meter beam (M2 6M7) exactly
>between them, six feet above the tribander. All booms are aligned the
>same and, for me, the combination works beautifully! Any interaction
>between the three is not large enough for me to measure.
>Pictures can be seen at http://www.qsl.net/w6old/antenna.html
>OK, there are several theories out there, but the most common and simplest
>follow is the one given in the ARRL handbook. The distance between beams
>can be half the lenght of the boom of the lowest band antenna...
>In your case half of what the tribander boom lenght is...
>Demetre - SV1ENS
The boom is 18 ft, and I dont have quite half that- bill
> with 10' of mast above the tower. Beginning at the tower
>top: KLM KT-34; 16 ele yagi on 222 mhz; 13 ele yagi on 144 mhz; 5 ele
>yagi on 50 mhz; 19 ele yagi on 432 mhz and 2 45 ele loop yagis on 1296
> The swr on all antennas are low and the beams are directional.
>Granted their patterns are probably not the best :) But at least they
>work and get me on the bands.
> 73 Matt W3UUM
>Bill, I have a Mosley PRO-57 at 80 feet that has been up for about 10 years
>so I was very familiar with the SWR curve on all five bands and also very
>knowledgeable of how it performed. Last year I put a M Sq. 5 element 6 Mtr.
>beam 5 feet above it. It did not change the PRO-57 at all as far as I could
>tell. I pointed the 6 mtr yagi in the same direction as the HF Yagi.
>I would plot the SWR curve on each band before you do anything then after
>you make changes plot the SWR curves again to see if the changes altered the
>Good Luck, Gary, K4MQG in SC.
>Just put it up anyway you can, it will work fine.
>I use an 8 foot boom 3el mounted 5 feet above
>an old TA-33, both pointed the same way.
>With six meters you can do fine with a 5 foot spacing.
>I have a 6M7 5 feet above my TH-6DXX, and 7 feet below my Hy-gain
>40 dipole. I see no interactions with any of the antennas.
>72 feet/77 feet/84 feet.
>Gud luck and see you on 6.
Darrel, NR3Y added the "sanity check" comments to the subject line- he had
>HI Bill I have about 5' between a TA-33 and a 6 element 6m beam.
>I have not noticed any problems witht the installation. 73's
The absolute optimum spacing would be 1 wavelength, ie 6m above your
existing yagi. That is obviously not an option, so you want to get the
antenna as far away as possible so the 6 ft possibility would be best.
As the 6m yagi is electrically small compared to the hf one and that it
is well within the hf yagis' capture area even with a 6ft spacing I
wouldexpect no change in the hf ant. The 6m yagi may have its pattern altered
a bit but it will still work FB. Thats my opinion on stacking
electrically, but mechanically I'll leave you to decide as I have no
idea abt ur wx and so on !
I look forward to hearing you on the magic band when we get some F2 this
autumn ! I hope you get as hooked on it as I am.......
M0BPQ (ex G7ACQ)
>Bill, I'd be interested in what you hear. I have a
>C31XR and about 7' of mast above it. I don't have the
>gear yet, but I've been thinking of a 6m beam just as
>you have. If you get a bunch of private replies,
>could you post a summary?
This is why I am making this summary
I want to thank ALL of you
Bill Aycock W4BSG EM64vr
Jackson County, AL
W4BSG is "vanity" this time, but was
earned by exam in 1954, the first time.
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