Simple Ham Radio Antennas

Over the past few days, mother Nature has released a torrent of heavy showers over the Hamakua Coast of Hawaii Island, making outdoor antenna work very wet and potentially dangerous.  When the weather turns bad, I usually lower all my verticals and inverted vees to ground level, disconnect antenna feed lines, and unplug my rig from the electrical mains.  I usually run my station off of deep-cycle marine batteries charged by photovoltaic panels, but sometimes, I use the electrical grid to run a bit more power (i.e. more than 50 watts) from my venerable Swan 100-MX. During today's passing showers, I decided to revive one of my old indoor antennas, a 10, 15, and 20 meter segmented dipole fed by a short piece of 50-ohm cable (RG-58).  This certainly isn't a new idea.  I've used the concept for outdoor antennas as well.  You can choose which of these bands to use by clipping or unclipping dipole segments.  AK7M and NV5I have published versions of this antenna...

Reworking a basic 10 meter ground plane antenna. After two fun-filled days of experiments with my horizontal 10 meter dipole, I decided to lower both masts, disassemble the dipole elements, and store them in the garage for possible emergency or portable use.  For some reason, the second mast made my "antenna farm" noticeable from the street and I opted to use only one mast for my next 10 meter antenna project.  I selected the fiberglass mast with the light green paint for antenna projects because it blended in well with the garden and the surrounding vegetation.  The spare MFJ mast would be used as a backup and emergency mast. Still, I wanted to work a bit more with 10 meters, which has shown some excellent propagation during the past month.  I had already used a 10 meter vertical dipole with great success during the past year.  This time, I wanted to experiment with a 10 meter ground plane antenna that could be easily built, erected, and taken down without...

A simple 10 meter dipole antenna. One of my favorite amateur radio bands is 10 meters.  It's unpredictable, capricious, and fun!  When propagation is favorable, you can works the world at QRP levels.  Basic antennas for this band are simple, cheap, and forgiving.  Most of the parts needed for this antenna can be bought at your neighborhood hardware store or home improvement outlet. Although 10 meters has been a bit sporatic over the past few days, I've been able to make some good contacts during daylight hours from my location on Hawaii Island--the island with the active Kilauea Volcano.  We live dangerously over here. MATERIALS: Two fiberglass or pvc masts, ranging from 20 to 30 feet tall (6.09 meters to 9.14 meters).  These masts will support the 10 meter half-wavelength "flat top" antenna.  Fortunately, my backyard can support two masts approximately 30 feet (9.14 meters) apart.  Anything more requires my dipoles to be in the inverted ...

A simple 15 meter vertical dipole. One of my favorite amateur radio bands is 15 meters.  The band is usually open during daylight hours and provides plenty of DX for those of us operating from the central Pacific.  Although most of my antennas are designed to be used on several bands (using ladder line, a 4:1 balun, and an antenna matchbox or "tuner"), I sometimes want to use an antenna specifically designed for a single band using whatever coaxial cable I have around the shack. In my location, I prefer using verticals, inverted vees, and loops because my backyard is small and room for a decent radial field is non-existent.  If I can't use a horizontal flat top dipole, I can always go up using a vertical dipole.  These antennas are simple to build, erect, and take down.  They are ideal for portable use with a telescoping fiberglass or pvc mast.  Once I finish testing a vertical dipole for a chosen band, I keep the pre-assembled antenna in a plastic sto...

RG-6 coaxial cable--an alternative to RG-8X, RG-58, and RG-8. Most amateur radio operators are familiar with the RG-8, RG-8X, and RG-58 family of coaxial cables.  These moderately priced cables are used for antenna feed lines and patch cords around the ham shack.  With a nominal impedance of 50 to 52 ohms, they work well with both contemporary transceivers and the old "boat anchors" we love to hate.  Many amateurs (such as yours truly) also use 300-ohm tv twinlead and 450-ohm ladder line to feed our antennas. With a suitable transmatch and a 4:1 balun, we can use an antenna on several bands. What if you don't have any ladder line, tv twinlead, or 50-ohm coaxial cable to feed your antenna?  Is there any other cable that can be used?  There certainly is.  RG-6 coaxial cable, the type used by cable companies , can often be used the same way as 50-ohm coaxial cable.  RG-6 usually refers to a cable with an 18 AWG center conductor and a 75-ohm character...

A simple 40 through 10 meter delta loop. One of the quietest and most versatile antennas I've used over the past few years has been a 40 through 10 meter delta loop fed with 450-ohm ladder line.  Used with a 4:1 balun, an antenna matchbox (i.e. "tuner), and a few feet (meters) of 50-ohm coaxial cable, this easy to build antenna will give you hours of both local and DX contacts. I built my original 40 meter delta loop with tuned feeders back in 1977, shortly after I passed my novice amateur license exam.  Since space was at a  premium (small backyard), money in limited supply (I was just starting my broadcast radio career after time in the Air Force), and I was recently married, extra funds for a tower and a super sophisticated rig were unavailable.  Like many of my fellow amateurs, I depended on wire antennas, used rigs, and basic designs to work the world.  My first rig was the venerable HW-101, a rig I must have rebuilt several times. Anyway, I found si...

A multi-band half-wavelength sloper antenna. This has been another beautiful, slightly windy day on Hawaii Island--a perfect time to build another antenna for DX adventure.  Although I've been happy with my 40 meter vertical with tuned counterpoise, I wanted to experiment a bit with another antenna I used frequently in my novice license days almost four decades ago. I quickly found my antenna experiment log book on the shelf of the radio room and turned to the pages marked "November-December 1977."  Those were some unusually dry months at my old QTH in Honokaa.  I was able to build several working verticals, loops, and slopers for my then new novice station. By feeding the sloper with 450-ohm ladder line and a 4:1 balun, I was able to cover three novice segments  in the 40, 15, and 10 meter amateur radio bands with few problems.  I knew the antenna would work on 20 meters, but I didn't hold a higher license (i.e. general, advanced, or extra class) to ...