Cheap & Easy Portable Antenna Hacks!

Revisiting an old topic.

I don’t do a lot of antenna articles because there is already so much information in circulation I can’t see much ground left to cover, at least that’s what I thought until new Off Grid Ham reader Rick sent a nice email that inspired this article. What are some cheap and easy ideas to make a portable antenna better, from an off grid perspective?

The off grid niche. portable antenna

To rehash the obvious, running off grid radio does not require a “special” antenna. Whatever works for conventionally-powered stations will also work off grid. However, off gridders tend to have different needs and operating goals. Some antennas fit these needs and goals better than others. portable antenna

I know from my own operating experience, running this blog for over seven years, and talking with other hams, that off grid amateurs disproportionally use QRP, lean towards portable operations (outdoors), and are less focused on having a big signal for the purpose of DX, contests, & awards. They also, by a very large margin, are involved with the survivalist/prepper movement and/or EMCOMM on some level.

If you are into amateur radio in whole or in part because you want communications when SHTF, then your equipment choices are going to be different from the guy who is a contester, DXer, or thinks it’s just a fun hobby. An analysis of those two demographics might itself be worthy of an entire Off Grid Ham article.

From the abstract to the real.

Now that we’ve lightly touched on the sociology and psychology of why operators may choose different equipment, the next question is “what are my options?” Your options as an off gridder are are for the most part the same as they are for everyone else. You’ll just have to make a few adaptations. As we have discussed many, many times on this blog, there will be tradeoffs and compromises. Here are a few ideas with a “cheap & easy” goal in mind:

The wire antenna. portable antenna

Perhaps the most fundamental of all antennas, the dipole has been around almost as long as radio itself. There are a few things an operator can do to make it more off-grid friendly. These ideas can apply to all other wire antennas too:

Lose some weight!

If you are running QRP power levels, there is no compelling reason to have a dipole with heavy gauge (16 or less) wire. Wire sizes between 18-22 gauge are perfectly acceptable for QRP. It’s less expensive, easy to work with, and coils nicely for easy transport.

Speaker wire is a popular material for light weight antennas. It’s easy to find and not particularly expensive. It would be a great choice. But there is something better. Much better.

The “holy grail” of off grid antenna wire.

The top of the QRP antenna wire pyramid is 22 gauge central office frame wire (sometimes referred to as cross connect wire). CO frame wire is incredibly strong for its size and does not easily stretch. It comes in a twisted pair. There is no need to separate the pair. Simply strip the insulation and terminate the bare wires together at each end. This turns the twisted pair into what is effectively one single conductor. The twist will have no meaningful effect on your send or receive signal.

Unfortunately, CO frame wire is used only by the telecommunications industry and is very hard to find for sale to the public. It can occasionally be found at swap meets. I was able to source this wire through my professional affiliations and can confirm that it makes a fantastic light weight antenna material.

The photo below is a 20 meter central office frame wire dipole with balun, rolled up for transport. It weighs 9.6 ounces (0.272 kg) including the balun and fits in a plastic sandwich bag.

OFF GRID HAM ORIGINAL PHOTO ©2022

Many hams work for the phone company, or have connections. Ask around. If all else fails, you’ve got nothing to lose by knocking on the door of your local central office and simply asking  the tech if you can have some frame wire. He/she will know what you are talking about. Every year they pay contractors to haul away thousands of feet of the stuff to the scrap yard, so it’s not a big deal to give some away. Many telephone central offices are not manned full time so you may have to make a few attempts to catch someone while they are there. Since techs set aside unwanted wire for recycling, “dumpster diving” will not likely produce any results. In any case, it will be well worth your effort if you can find some.

If you cannot source central office frame wire, light gauge speaker or doorbell wire will work just fine but will not be as strong and stretch resistant.

Baluns and ununs.

Almost any antenna fed by coax can be improved by adding a balun or a unun. These devices are essentially transformers that manage the impedance difference between your feedline and the antenna and prevent common mode current. Common mode current is undesirable RF energy that flows along the outer braid or shield of the coax; it contributes to inefficiency and poor antenna performance.

A balun is used on antennas where all elements are the same length, such as a dipole. A unun is used on antennas where the elements are not the same length, such as a random long wire.

Commercially made baluns and ununs are relatively inexpensive. It is also fairly easy to make your own; YouTube has many great DIY videos.

Random wire antenna, version 3. OFF GRID HAM ORIGINAL GRAPHIC ©2016

Ham sticks.

Another popular cheap & easy option is the ham stick dipole. Two mobile antenna whips (intended for use on a car) are screwed into a mounting. A coax connector on the mounting directs the signal to the appropriate element. The fitting usually has a clamp for mounting on a mast or other support.

Ham stick dipoles are very effective & inexpensive antennas and can usually handle power higher than QRP. The disadvantages: 1) they have a tight bandwidth and can be difficult to tune. An antenna tuner may be needed; 2) they cannot be coiled up small like a wire, 3) they also require a support mast. Depending on your resources, needs, and logistical situation, transporting them for portable operation may be a problem. Lastly, they are only good for one band. You’ll need a totally separate set of ham sticks for every band you want to operate.

HAM STICK MOUNTING BRACKET. OFF GRID HAM ORIGINAL PHOTO ©2022

Telescoping antennas.

There are some great commercially made telescoping antennas that are about as close to plug-and-play as you can get.

The Chameleon CHA SS17 extends to 17 feet and is 27 inches when collapsed. The manufacture claims it will work on 20-6 meters with no need for a loading coil. MFJ offers the MFJ-1979, which is almost exactly the same as the CHA SS17. I have not personally used either of these antennas but OGH readers have reported excellent results with them. They cost between $70.00-$80.00 and you’ll probably have to also buy some adapters and mounting hardware to make them work. If light weight, small size, and portability are your top priority then a telescoping antenna is your best pick. portable antenna

In conclusion.

Any antenna will technically work in an off grid application. However, there are many simple ideas one can employ to make a good antenna better and more adapted to specific off grid needs. These hacks are not necessarily difficult or expensive. With a little creativity, you can come up with a very effective —and very cheap & easy— antenna for your off grid radio station.

Do you know of any off grid antenna hacks not mentioned in this article? Tell us in the comment section below.