As one who was a rover for over 30 years (often in the top 5 nationally)
please let me offer some common sense..
(1) I cant think of any reason to carry a 50 ft pushup mast... A 20 footer
would make more sense, less weight, only 2 guys, and get your antennas high
enough to work anything. A 20 footer that's 3 or 4 sections would be a big
advantage.
(2) Learn quickly that 30 ft long yagis are a huge liability physically
over any additional gain they will provide.due their length. Strive for 12
to 15 ft long antennas max... MAX!
(3) If you can, set up EVERY antenna you plan to use on a mast(s) already
bolted to the rover vehicle and go down the road with antennas at a max of
12 to 13 ft high as gas stations and overpasses are not all created equal.
Turning the vehicle to aim the antennas make things much MUCH faster.
I have many more ROVER GUIDELINES that I have learned over the 30 years I
was an active Rover contester but don't have time to post them here.
Trust me when I say a 50FT pushup is only for fixed stations use, not a
ROVER...
Visit K7XC.TRIPOD.COM for pictures of what I am talking about.
73s de Tim - K7XC - DM09jh... sk
On Wed, Dec 28, 2016 at 4:33 AM, Patrick Thomas <p-thomas@mindspring.com>
wrote:
> Hey all,
>
> I've been considering augmenting the park-and-go rover setup with a
> push-up mast. However, I have noticed that the Rohn H50, etc., explicitly
> state that they are "not recommended" for use with yagis. And sure,
> physics would suggest that if you have a 15' antenna boom, you are likely
> to have more off-axis "arm" acting on the top of the mast, versus a
> vertical or even a dish. On the other hand, I don't know if they only say
> that to protect themselves against people who use H50s as semi-permanent
> rooftop installations in 80MPH wind zones with heavy ice.
>
> So what's the verdict? I'm sure it's "possible" but is it safe to use a
> large 2m yagi on an H50 when properly guyed, on a day with gentle breezes?
> Or is it indeed "not recommended" under any conditions due to instability,
> etc? For that matter, what about the weight of a rotor that high up?
>
> (And yes, I'm still working on the halo stack, so worst case I could
> always hike that up the line... but would love to have the extra gain and
> directionality from the yagi.)
>
> Thanks,
>
> Patrick
> KB8DGC
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