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Portable QRP Ops

There is nothing more satisfying than taking a portable radio outside on a warm sunny day, throwing some wire up in a tree and making some QSOs on the radio. So I keep the portable station in the car, because you never know when the opportunity is going to present itself.  It always pays to be ready.

So ..... what about antennas?  I can't very well bring the W3EDP or the Butternut with me when I leave the home station !  

There are probably as many solutions as to what to use for a portable antenna as there are Hams.  I go with three or four basic setups.  Keep in mind that when I'm out operating from the field, I want to do just that ... OPERATE!  The goal is to make QSOs, and not fiddle with antennas all day.


Buddistick

This is a shortened vertical with a coil.  Basically, you pick a point on the coil to tap into depending on the frequency that you are interested in and you go to town.  The Buddisitick is great because it is extremely portable, requires no trees and can be used anywhere.  It works better, however, if you get it elevated.  I have used a 12 foot painter's pole to elevate my Buddistick.  I keep an Autek antenna analyzer in the pack so that I can set the antenna up with as low an SWR as possible.  It uses a counterpoise or set of radials to form the other side of a vertical dipole.  Changing bands? A bit more involved as the tap settings have to be changed and in the counterpoise length has to be adjusted.  BUT, once is is set up, it works great!  I have worked plenty of DX with my Buddisitck.  I wouldn't use this as a permanent base antenna as it IS a compromise antennas; but out in a field on a warm, sunny day it will get your signal out there. And, when there are no trees to support wires - these are a very good way to go. And if you can get a Buddistick on a magmount on top of your car? So much the better - see the CQ article below.

Buddistick mounted on painter's pole behind cabin in Lake George, NY

Doublet Antennas

I carry two doublet antennas in the pack.  The NorCal Doublet and a homebrewed 88 foot extended Double Zepp.  Both are made of Radio Shack speaker wire.  They were cheap to make and I wouldn't be heartbroken if something happened to either.  Super easy to change bands too - I just change frequency and let the K1's internal antenna tuner do its thing.  Setup is relatively quick; but this is they type of antenna that you use if you're going to be in one location for a couple of hours.  To use one of these, you are going to need trees or a center support if you intend to go with an Inverted Vee configuration.  For that purpose, I keep a 20 foot Crappie stick fishing pole in the back of the car.  It's called a "Black Widow" that I bought from Cabela's.  It collapses down to about 30 inches and does pretty good duty of getting the center of the doublets up there.  I also have a 31 foot Jackite pole.  It is taller and sturdier than the fishing poles and it doesn't bend over at the top (as much).

Courtesy of NorCal


EFHW Antennas

They are a major part of my portable operations antenna arsenal.  For 20 and 40  and 10 Meters, I use a PAR ENDFEDZ 10/20/40 MKII.  I used this set up for Flight of the Bumblebees 2012 and while on vacation at Lake George.  In both instances, I was very pleased with the results.  I also keep a home-brewed EARCHI  4-6 Meter end fed in the pack.  The EARCHI is a bit longer than the PAR, but I also get 17 and 15 Meters with it - just hit the auto-tune button on my KX3 and I'm there! The only drawback is that you have to have a fairly tall tree to act as a support for the non-radio end of the antenna.  The really great thing about using one of these is that there's no thinking about it - get the wire up in the air somehow, hook up your radio and start operating!

I also keep an MFJ-1982LP end fed in the pack. This is the antenna I use for Field Day. It has a very good SWR on all bands 80 through 10 Meters. It will even tune on 160 Meters with an higher SWR but still under 2:1.  This one is so long, though, that it has to be set up as an Inverted Vee with a center support and supports at both ends. Excellent antenna, but not as quick and easy as the others.




Getting the antenna up in a tree

Now that you're out in the Great Outdoors, just how do you go about getting that antenna up in the tree?  This is a necessary evil when using a doublet, dipole, EFHW or other wire antenna.  You can use a "throw bag" like Diana Eng uses in the above video; or if you're like Jim W1PID you can use a partially filled water bottle.  Other Hams have devised various pneumatic spud guns, some use the venerable bow and arrow.  I used to use a homebrewed version of the EZ-Hang.  It consists of nothing more than a corner brace, a fishing reel and a sling shot and a 1 ounce fishing weight. But I have since found out from my brother-in-law (who is a police officer) that sling shots are considered to be a 4th Class weapon in the venerable state of New Jersey, so I now use a Joplin ARC antenna launcher that I built from the kit they offer.



How about when there are no trees?

Trees are good. Trees are nice.  How do you use an EFHW antenna when there are no trees around? I've devised a "drive on" mast base that works rather well.  It holds my 31 ft Jackite pole securely enough to be used as support.

I started with an oak plank, which is about a foot wide by four feet long.  I chose oak because it's a hardwood and will not crunch, cry, whimper or complain when you drive a vehicle onto it.  In fact, even after using it a lot, it still looks like it's never been under a tire!  I took the board and cut it into two equal 2 foot pieces.


The I took some hinges and made it a four foot board again, but this one bends!



U bolts were added to hold the Jackite in place:


And to stabilize the vertical member, so that it won't tilt in either direction, towards or away from the vehicle, I added a corner brace.


The corner brace is bolted and secured to the vertical member only.  I secure it to the horizontal member by driving onto it!  The weight of my vehicle keeps it in place.  So far, it works very well, even in breezy conditions without any problems.


I suppose there are other more elegant solutions.  But this one folds and stores easy, was inexpensive to build and works rather well.  I may not be great at homebrewing rigs; but every now and then I cobble something together that works well.

Magloops

One final type of antenna you might want to consider - magnetic loop antennas, or magloops as they are commonly called. Some consider these a last resort, but in actuality, they can work pretty well.


I have two - my homebrew version displayed in the picture above and an AlexLoop. The AlexLoop is a bit more convenient to travel with as it breaks down into smaller components than mine, but both perform about as equally well. My homebrewed version came in at under $100 to build. You can search the main portion of the blog for "magloop" to read about that adventure. It was fun and was a satisfying build. In fact my very first QSO with it was with a Ham in Italy while I was testing it from my dining room table in New Jersey!

While I have worked into Europe quite easily and all around the USA and Canada with my loops, I'm enough of an old timer to still prefer using a wire or a vertical if I can. However, in a pinch, a magloop will serve you very well. And there will be times when a magloop may be your only practical choice - you may be in a portable situation where there are no trees, or perhaps there's not enough real estate available to set up a vertical with radials, or maybe your operating position has to be away from your vehicle. In any of these instances, a magloop can be your best friend. And despite what you've heard they are pretty easy to use.  I just tune the variable capacitor of the loop to the spot where I hear maximum background noise on the band that I am working. My KX3 displays the SWR, so I hit the transmit button and then tweak the variable cap on the magloop for as close to 1:1 as I can get it. It takes a little getting used to, but it becomes real easy in a snap. I also find that I can move a few kHz in either direction without having to retune the magloop.  The tuning of a magloop IS critical, but not as critical as some would have you believe. For example, if I tune for a 1:1 SWR at 14.061 MHz, I can usually operate from 14.063 to maybe 14.059 without retuning and still have a respectable SWR. Of course, YMMV.

Here's an article that I wrote that was published in the February 2014 edition of CQ Magazine: