Pete,
When I am in motion, I use a 5/8 wave 2m vertical on six. I have been able to
work stuff when I am driving down the highway. I use a M2 loop for 2M and one
on 70cm will in motion.
I also use a walk up mast with a 6M Moxon and and Elk for 2m and 70cm.
Hope that helps to stir your problem solving juices.
> Message: 3
> Date: Wed, 3 Sep 2014 20:45:39 -0700
> From: Pete Kobak via VHFcontesting <vhfcontesting@contesting.com>
> To: "vhfcontesting@contesting.com" <vhfcontesting@contesting.com>
> Subject: [VHFcontesting] rover antenna alternatives
> Message-ID:
> <1409802339.66904.YahooMailNeo@web121805.mail.ne1.yahoo.com>
> Content-Type: text/plain; charset=us-ascii
>
> Beginner rover, participated in the July CQ contest from 8 grids. My setup
> takes a long time (30-40 minutes) to construct and break down, so travel and
> setup/breakdown leaves little time for making contacts. [I have a ~30 ft
> walk-up mast on trailer hitch (a Penninger Radio system) and keep the
> antennas inside the minivan, so I have to assemble the mast and assemble all
> 3 antennas on the mast and connect coax each time.] For Sept., I'll have a
> short boom 6m 3el, a 2m 7el, and a 432 15el.
>
> I've been trying to mount loop antennas (M2 "HO" series) on the roof rack
> rails so I have some limited capabilities on the road and quick grid stops
> (in addition to the walk-up mast for longer stops). However, I'm getting
> frustrated trying to mount them (especially the 6m) because they use skinny
> half-inch masts with standard 3/8 threads. Way too whippy IMHO for highway
> speeds and there would be tremendous stress on the bolt or nut holding the
> mast on the mounting plate. Tried using a very stiff antenna spring, but the
> 6m just flopped over from it's (non-symmetrical) weight. I could get some
> strain relief with a couple of guy ropes, but I can't get guys in 3
> directions, just 2 at a right angle. I'm thinking of using PVC to get both
> pull and push forces on the masts, but the arrangement I'm starting to try is
> a horrible hack of cut up PVC connectors and hose clamps.
>
> Since the loop antennas are turning into a big project anyway, I was
> considering mounting my yagis for use on the road. I'm pretty nervous about
> it, but I think mechanically I could do it from the trailer hitch with my
> existing system. Here's some concerns (besides the concern that the antennas
> will come flying off on the highway and cause a horrific accident):
> 1. I'll only have 5ft of mast or less above the roof. Having the 432
> lowest at 1 foot above the roof, that only leaves 2ft max spacing between the
> antennas. Is it even worth doing with the antennas squeezed so close together?
>
> 2. I don't have a Moxon for 6m, just the short 3el. Having the 6m point
> down the major axis of the van would be too wide for travel, so I'll have to
> have it at a right angle to the other two antennas pointing down the major
> axis. I understand that will be a PITA to have to turn 90 degrees when
> changing bands with a contact, but my bigger concern is how much performance
> will be hurt.
>
> 3. I've seen plenty of pictures of rovers with antennas overhanging the
> back of the vehicle, but I've always wondered about the legality and safety
> of that arrangement. What if any flags and lights do you put on the
> overhanging antennas? My antennas will extend 42-56 inches back from the
> trailer hitch, which is right against the bumper.
> 4. OTOH, I'm hoping when I stop to do a full setup, I'll save some time by
> having fully-assembled antennas and coax on the top mast segment already ...
> though taking off the populated segment and moving it to the end of the
> assembled long mast will be a challenge.
> Thanks for reading through this long post. Is there a better way to do the HO
> loops, or should I just use two guy ropes and stop worrying? Or, is the
> compromise mounting of the yagis a better way to go? I appreciate your
> thoughts.
>
> -- Pete K0BAK
>
Sent from my iPad
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