I strongly suspect that the HF yagis should follow the same patterns as the
VHF antennas. Find the stacking distance and keep them out of each other's
apertures. If possible, avoid harmonically related yagis inside their
aperture. It's hard with many of the contest bands being harmonics or near
harmonics , but you do what you can.
K1WHS knows his stuff, that document and others he has written are staples.
73,
Sean WA1TE
On Tue, Oct 17, 2017, 19:32 Don W7WLL <w7wll@arrl.net> wrote:
> THAT is a very informative article Larry. wish it had been written to cover
> the common HF antenna stacking discussions, particularly when it comes to
> the stacking of dissimilar multiband antennas like a 10/15/20 tribander and
> a second multiband antenna such as a 12/15 or similar which pose a whole
> set
> of different problems vs the stacking of single banders.
>
> Discussion seems to always go back to 'you must have x/spacing'.
> Unfortunately, many hams just can't achieve that goal but do want to
> operate
> with HF yagi's to access the number of upper HF bands, so do what they can.
>
> Height above ground minimums for HF yagi's is another often discussed
> issue.
> Many hams who have a HF yagi may not be able to get above 20-25 feet.
> Tain't
> optimum, but it will work.
>
> In the end you do what you gotta do to get on the air, certainly better
> than
> saying I can't do what the experts and theory say I must do or should do so
> I'll just give up (I've heard that too, particularly from newer hams).
>
> A lot of 'learning' comes from the discussions on the two topics, spacing
> and height of HF yagi's. I always look forward to those who explain what we
> should do and those who explain what they HAD to do (and the results).
>
> Tnx to all for the contributions you make on these topics.
>
> Don W7WLL
>
> -----Original Message-----
> From: Larry Banks
> Sent: Tuesday, October 17, 2017 2:10 PM
> To: Marty s ; towertalk@contesting.com
> Subject: Re: [TowerTalk] VHF/UHF Stack Spacing?
>
> Hi Marty,
>
> Check this out, it may be helpful:
>
> http://directivesystems.com/contact-us/tech-notes/stacking-dis-similar-yagis/
>
> I assume you also know about the NEWS group: http://www.newsvhf.com/
>
> 73 -- Larry -- W1DYJ
> YCCC
>
>
>
>
> -----Original Message-----
> From: Marty s
> Sent: Tuesday, October 17, 2017 9:17
> To: towertalk@contesting.com
> Subject: [TowerTalk] VHF/UHF Stack Spacing?
>
> Hi All,
>
> I'm in the process of building a VHF/UHF rover on a former ENG truck mast.
> I plan on having 6m - 903 on the mast. What is your rule of thumb on
> VHF/UHF Yagi and Looper spacing (not stacking the same antenna)... any
> experience with this would be appreciated!
>
>
> Marty
> KC1CWF
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