EMCOMM / Technical Articles

EMCOMM: Antennas on the Go

The rigs are ready to go. What’s next? Choosing the right antenna is an important aspect of successful portable operations. While most people know that an antenna is key to good reception and transmission, you’ll also need to factor in finding ones that are portable and can be easily deployed. Obviously, some sacrifices are going to have to be made.

What are the Options?

Wire antennas can be simple, quickly deployed, and inexpensive options. They can be purchased or homemade, cut to a perfect resonant length or used with an antenna tuner. Choose from single-band or multi-band versions. Just throw them up in a tree or attach them to a pole and they’re ready to go. But you’ll need to consider…

  • How do you deploy the wire if there are no trees or high places where you intend to operate?
  • How high does the wire need to be?
  • How do you get the wire back down?

Of course, how high you install your antenna will be influenced by who you are trying to contact. For example, many ARES applications use NVIS configurations (a topic that demands its own blog post). In this case, the wire would be closer to the ground as people are typically contacting other people within their section. If you are calling across the country or DXing, a higher configuration is often the key to success.

Be sure to include masts in your go-kit in case there are very few or no trees where you will be operating. An end-fed wire would require one mast, and a dipole wire may require up to three. Of course, there are a wide variety of other wire antenna placements and configurations that can be used to fit your particular location.

Throwing a rope in a tree and using a pulley system is a very effective way to easily raise and lower a wire antenna. You may also find that a wire antenna launcher, like the EZ Hang Square Shot Weight Launcher Kit shown below, is a great tool for reaching just the right branch.

Single-band wire dipoles strung from trees on Winter Field Day.

End-fed wire antenna from Chameleon (EMCOMM-III, 160M-10M, 100W SSB or 50W CW)
Chameleon MPAS 2.0 Portable HF Antenna System

Verticals can be another good choice for portable operations. There are many vertical antenna manufacturers offering a wide variety of price ranges. Vertical antennas have a low angle of radiation, providing the user with a good probability of making contacts around the world. Radials or counterpoises are usually required for verticals; radials are most often realized as lengths of wire spread about and lying on the ground. Portable vertical antennas are most often multi-band with a coil used at different positions for band changes.

Vertical with coil, 80M-6M, 200W SSB, 100W CW, and 25W Digital
Homemade coil for portable HF operations
Vertical without coil, 213″ whip: 6M, 10M, 12M, 15M, 17M, 20M

The highly portable 1,200W PEP TW Antenna Globetrotter Package from DX Engineering covers 5 bands (20-10M) with the capability of adding 80, 40, or 30M. It comes with antenna structure, switchable band box, 65.5 foot control cable, controller console, and permanent antenna mount.

Hybrids: Then there are creative ways to mix the two types: vertical dipoles, raised dipoles, etc. They can be with or without coil loading depending on the bands that one is trying to operate. Tune each side individually first and then use them as a matching pair.

Hamsticks in a dipole configuration

Coils and whips, 40M-10M

Loop antennas can be made of various materials like metals or coax. A portable magnetic loop antenna can be a great solution for the outdoor radio enthusiast. Many of these loops automatically tune to the desired band. 

MFJ-1788 Super Hi-Q Loop Antenna

The AlexLoop HamPack Portable Magnetic Loop Antenna System for 40-10M comes with backpack, loop antenna, and tuner. The system can easily be taken into the field and assembled in less than two minutes.

Miscellaneous: There are many other options not listed here, including mobile applications in any form. Operators often develop their own antennas and put a twist on them.

Have you ever used a Slinky antenna?

Have fun designing your own antennas. Questions? Share them in the comments below or email me at KE8FMJ@arrl.net.

Leave a Reply