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PAC12/Wolf River Vert compared to EFHW/Dipoles

I’m very excited to get busy doing SOTA this year, as I have decided to replace my MFJ-9200 with a KX2 or KX3. The added capability is exciting and like any time I get a new “toy” I like to use it.

For my prior activations, I have used the QRPGuys EFHW tuner with reasonable success. It is however a bit flimsy, getting the slingshot out and getting a line over a tree is time consuming, and changing bands is a serious effort.

I’m looking to get a new SOTA / portable antenna to enjoy with my new radio and improve my SOTA experience. I’m thinking the PAC-12 vertical or Wolf River Coils TIA Vertical make nice options.

I’ve also flirted with the idea of getting a fiberglass mast and sticking with EFHW and/or dipoles (PAC-12 makes a nice 40/20 trap dipole kit as well).

I’m leaning towards the verticals and the reason is pretty simple. Here in the W3 association most summits are treed, VERY TREED. And we usually have a great ratio of Deciduous Trees vs. Evergreen, which in my opinion make things more difficult. On the other side of the coin, I want to do some Adirondack (upstate New York in W2) Summits in the near future, many of which have summits above the treeline and feature only rock.

I was looking for advice from people who have used both options.
My Needs In Order of Importance:

  1. Ease of Installation/Disassembly
  2. Signal Efficiency
  3. Fits in a pack
  4. Relatively Light Weight

I’m willing to pack along plenty of extra radials to make a full compliment in order to put out a good signal with the verticals. Wire is light.

Thanks in Advance,
N3TWM - Evan

Hi Evan,
There is not going to be one antenna that is “ideal” for all summits.
Worth bearing in mind on treed summits, horizontal (or usually Inverted-V) dipoles work better than verticals which are de-tuned by the trees. On non-treed summits where there are less suports for a F/G mast supporting an Inverted-V (and possibly not enough space to run out the dipole wires), a tripod-mounted vertical is probably a better choice.

If you are looking for DX, then a vertical could be a better choice. If you need the numbers from more local stations then a horizontal (NVIS) antenna is going to server better.

73 Ed.

Evan,

The Pac-12 ground mounted vertical is a fantastic antenna for SOTA and I’ve been using one for nearly 4 years. Here in the Sierras I often operate above the tree-line so I can’t count on having trees to hang a wire from. Also, having a mast sticking out of my pack in impractical for me when traveling cross-country.

Considering your list of requirements, I would recommend trying a Pac-12:

1)The Pac-12 can be set-up in under 5 minutes including laying out 6-8 ground radials.

2)The efficiency of a tuned wire antenna will be better then the Pac-12 however I’ve always been able to make many more then my 4 required contacts.

3)The Pack-12 can be rolled into a tight 13”X 1.5” bundle and weighs 1 pound including a coil for 20 and 40 meters.

If you’re reasonably handy, you could make your own Pac-12 for under $35 U.S. Instructions on how to make a homebrewed version of the Pac-12 can be found here: http://www.qsl.net/ash_ares/PAC-12%20Antenna.pdf

73,
Jordan WC6J

One other possibility is to always take a telescopic fishing pole …

If you have space put up an inverted V dipole, this will be best for efficiency.

If there is no space then try a vertical, but not a heavily loaded one like the PAC-12. Something like the VK7JJ Squid Pole, see:

http://www.perite.com/vk7jj/squidpoles.html

This will be much more efficient than the PAC-12 and as you say, wire is light so carrying both the wire for the dipole and for the vertical won’t be a problem.

73, Colin G8TMV

PS there is no truth in the rumour that you have to erect it upside down in the Northern Hemisphere.

I’ve never found trees to be an issue operating portable - the more there are, the harder it is to miss. :wink: Leave the slingshot at home. Put a screw eye into a golfball and take a spool of cheap 12-15lb fishing monofilament. I have no problem flinging that 60’ or so. Usually a pretty quick deployment. For barren summits, telescoping crappie pole of 17-23’ will hoist the endfed. PAC12 or MP1 are also small, lightweight options. Buddistick is less so. There are other options I’ve used in the way of wire antennas - 20m delta loop, NorCal Doublet, etc.

Or if Evan doesn’t want to have to bother with radials - the end fed, 1/4 wave stub matched “J-Pole” vertical HF antenna discussed in another thread on this reflector may be of interest to0. (this is a single band antenna however).

For support masts, that are packed small and light but high enough to get an Inverted-V dipole in the air - take a look at this one (I have two of them):

http://www.lambdahalbe.de/zubehoer/gfk-masten/6m-gfk-mast/index.html

Dont be put offf by the fact the shop is in Germany - shipping costs out of Germany are cheap in comparison with the US, the UK etc.

73 Ed.

Evan,
Just put up your resonant link dipole at 8-9ft and everything will be easy… no need to mess with launching weights or whatever…
If you feel like you want to improve things… add a (wire) reflector on the ground beneath the dipole with a length ~+5%

Low dipoles do work…

Richard // N2GBR

I don’t want to start a what is better than x flame war.

Have a look at my results. Only last 2 were not with the PAC 12. Gone from barely activate or be heard to pages filled with contacts after moving from the pac12 to the dipole. However horses for courses.

Either check my reports or watch the videos - YouTube.com/c/wadeabout

I will leave it there

W

VK1FWBD

Hi Evan,

I’ve found that a monoband EFHW antenna propped up on a single mast (I use an avalanche probe) in inverted-V (or inverted L) is the easiest to put up/tear down in places without trees. It is not as efficient as my linked/trapped dipoles, but they both fit in my pack very well and, using 22 awg wire, are reasonably lightweight. My circumstances are a bit different from yours, as I usually operate on summits without trees, but I’ve found that it’s relatively straightforward to put up a short mast (~3m) by piling rocks up and wedging it in, or lashing it to a larger rock with parachute cord or some small bungees. This generally puts out an NVIS pattern on 20m. For more regional contacts I switch to 40m. I know one operator who just lays out an 80m dipole on the ground and has good success with 5W using CW.

Broadly speaking, using a short radiator with loading coils will dramatically reduce the efficiency of the antenna. By all means experiment with it (that’s part of the fun!) but be aware that getting a resonant length of wire out, even if it’s a bit low, will probably yield a better signal. If you’d like to play with a few homemade versions then you might think about picking up this little gadget to make adding/removing inductance easier, and just run some wire up a short support mast.

Good luck and have fun!

Thanks all for the comments. It seems like the general consensus is that the vertical, while easier to install is significantly reduced in efficiency. I did end up buying a difference Pacific Antenna product, their new 20/40 trap dipole kit.

http://www.qrpkits.com/dualbanddipole.html

I know the traps will have some loss on 40m, but I’m sure it won’t be much, or at least not as much as the PAC-12 vertical. Instant switching between 40/20 as well, with no links to mess with.

I guess I’ll suffer through putting up wire. I always have a hard time of it though. Things get tangled, lots of rope and whatnot in the air. For those who say getting a dipole in the air is easier than one of those verticals, I still don’t believe it. Not around here at least. I may try Richard’s method of installing them low to the ground for now, see if that makes things easier.

N3TWM

Hi Evan,
Please take a look at a short (5-6m extended 60cm collapsed) telescopic fibreglass pole as the support for your new trapped dipole. All you need is a fence post, hole between rocks or smaller tree trunk to “bungy” (rubber bands) it to. The two legs of the dipole (inverted V format) double as supports to keep the top of the pole vertical and there no throwing wires or ropes into tree branches required.

73 Ed.

Like this!

2 Likes

OK, fess up. How did you get that guy wire on the left in place!
Awesome photo!!
Compton

A well trained hummingbird named Marty. I hook him up with sugar water, he hangs out at the end of the guyline until I’ve got 4 QSOs.

Nah, the summit ridge just wraps around, still a pretty sharp drop off though. Here’s the antenna from that end:

2 Likes

@N3TWM that’s a good choice especially as you’re a CW operator… :wink:

RJ // N2GBR

FWIW, one of the things I enjoy about portable operation is trying out various antennas. I’ve used everything from dipoles to homebrew buddistick to 9:1 unun endfed to phased verticals to delta loop… Have fun, play around, experiment & good luck! We’ll be listening…