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[N3KXZ]

I recently got a 2m/70cm rig to use as a base station. In looking around for antenna options it occurs to me that while the local repeater uses vertical polarization, other modes use horizontal orientation-  SSB simplex  (which is common in my area), not sure about APRS, packet or other digital modes...

So... do people who use different modes have two different antennas for 2m/70cm? one for vertical and one for horizontal polarization?

Would there be a good single solution for both polarizations? Not yet sure what I will be using it for, but I would like to be as flexible as possible since I am looking to put something permanent on my house roof (up to 50 watts) and would like to do it only once :-).

Thanks,
Keith
N3KXZ

[K6JH]

SSB, CW, FT8, weak signal modes use horizontal. If you have an SSB radio like a ft991 you might consider this. Yagis or perhaps horizontal loops.

FM, Packet (still around?), dastardly, c4fm, dmv will all be vertical. The typical 2m/70cm mobile will be this. Verticals, or vertical yagis.

The only dual polarization antennas I’m aware of are the cross polarized yagis with relays to pick hor, vert, or maybe circular polarization. Although there might be some cp Omni antennas - which will loose 3db when used for vert or horizontal signals.

[WB6BYU]

The common solution is to use separate antennas - often an
omni vertical for FM modes, and a yagi for weak signal work
on CW/SSB/etc.  (Depends, of course, how far you want to
work on the FM modes.)

Often beams are optimized for one part of the band, either
144 - 144.5 MHz or 145 - 148 MHz, on the assumption that
they will be used for one or the other, although there are
designs that will cover the whole band.

It is possible to use a single yagi and rotate the boom to
move the elements from vertical to horizontal or vice versa.
I've see this done with a couple of bearings, a lever arm,
and a pull rope, or the type of antenna rotator that is hollow
through the center could be used.

With a quad you only have to rotate the driven element
(or the back two if that is more convenient).  Or the driven
element can have two feedpoints (and separate feedlines).
The antenna can then also be used for circular polarization
if desired by driving both feedpoints.

[G4AON]

I have a weekday 2m SSB sked over a 40 mile path, plus occasional longer distance QSOs when there is a lift. I replaced a dual band Diamond X50N with a TV rotator and lightweight 6 ele horizontally polarised yagi. I don’t regret the swap as there was little local digital or FM activity.

Only you can decide the best option, if your mast can take it, perhaps a lightweight horizontal yagi and a modest length dual band co-linear? The X50N is about 5 foot long and very light.

73 Dave

[KI5FJ]

Keith, Glad to see almost new blood entering the hobby! I suggest you confine your V/UHF ops to local FM Vertical Polarization. I have operated 20 Watts, horizontal polarization on 144 & 432 MHz, FT-8 using a small yagi. I consider this low power, low gain antenna a local play-thing. Keep the feed-line losses low, position a dual band vertical as high and as close to the shack as possible. Use the lowest loss cable you can afford. DXE-400MAX is a good choice. I recommend you always use commercially attached water resistant connectors. My FM rig is IC-207, I use the FT-991A for all other modes / bands. A IC-756Pro3 is cabled for 50 MHz. A IC-746 is a Field Day / Emergency Power rig. Radio Active since 1961. Drop a email via QRZ address.73 & Be Well, Joe O, K I 5 F J, NNNN

[NA4IT]

I would use a good omni for vertical work, and a beam for horizontal. The longer, the better, but harder to pinpoint stations. Might even consider a loop for omni horizontal.

[KF4HR]

Keith - Most all 2m/70cm FM communications (including APRS) you'll want to use an omni-direction (vertical) antenna.  Ideally you'll want to choose a vertical antenna which provides a fair amount of gain, so you can copy stations 360 degrees around your location and which is mounted high and in the clear so  you have good range.  The Comet GP-9 vertical is a nice option for this. 

For best performance with SSB communications you'll want to use a horizontally polarized yagi.  One nice option is offered by the M2 (M-Squared) company, their model 2M12.  Since the 2M12 antenna covers the entire 2M band (144-148mhz) it can be mounted horizontally or vertically, so for example if you wish you could put up two 2M12's, one mounted for horizontal polarization for SSB work, and a 2nd 2M12 mounted vertically which would provide long distance FM Simplex or Repeater communications.  A similar two yagi arrangement could be used to provide similar SSB and long distance FM results on UHF.  GL

KF4HR