Tag Archives: Homebrew Antennas

The POTA Babe Checks In

By Teri KO4WFP

Glenn W4YES and I headed to Camden, SC the first week of April for some much needed rest and relaxation. Usually when I travel, I schedule a POTA activation or two. However, this trip I decided to try something new – getting on the air QRP at our Airbnb.

Camden is the oldest inland community in South Carolina. According to the town’s website, the earliest permanent settlers arrived in 1750. They experienced a crushing defeat during the Revolutionary War when the Patriots were defeated in the Battle of Camden. After the Civil War, the town “evolved into a tourist mecca for Northeners and Midwesterners seeking a warmer winter climate.” Those tourists brought money and an equine culture developed around racing and polo.

Our first day in Camden, we visited the Revolutionary War Museum. Though small in size, the museum’s exhibits are of excellent quality. They do a great job explaining who lived in the area, the quandary they faced as to whether to be a Loyalist or Patriot (it wasn’t as easy a choice as it might appear), and battles fought there.

Our second day, we explored the National Steeplechase Museum. This museum explores the history of steeplechasing and the personalities involved – owners, trainers, jockeys as well as those who care for the horses. The museum pays homage to Marion duPont Scott who developed the Springdale Race Course where the museum is located. This race course hosts two prominent annual competitions – the Carolina Cup and the Colonial Cup.

National Steeplechase Museum

an old scale used to weigh jockeys
trophy room

We also spent some time driving through and walking in the historic neighborhoods of the city. The weather was gorgeous! Everywhere we looked, there were flowers – azaleas, wisteria, viburnum, and dogwoods (including the pink variety we do not see in Savannah).

a dogwood in full splendor
azaleas at the corner of a home
viburnum
pink dogwood

After exploring the area, it was time to explore the airwaves QRP at our Airbnb. To do this, I brought Craig, my KX2, and a home-brew linked dipole antenna. This is an antenna I built three years ago, when I first got into ham radio. At that time, I had no home station but wanted to get on the air portable for POTA. Despite knowing almost nothing about antennas, I built a usable dipole that became my main POTA antenna for quite a while.

the homebrew linked dipole (photo from GA State Parks on the Air event)

Why did I bring this antenna to Camden? I have the opportunity this month to try the CFT1, a QRP transceiver, by Jonathan KM4CFT. Because the rig does not have an internal antenna tuner, I am reacquainting myself with the subject of resonance and why it matters in antennas.

I set up a home-brew linked dipole Wednesday evening under some trees in a space between the Airbnb and a small lake on the property. The antenna was roughly 20 feet in the air.

the lake from the Airbnb
2nd location for antenna by lake

 My RigExpert Stick analyzer gave me 2.1 at 7.040 –

Thinking I could do better, I moved the antenna (a real pain to do with a dipole) to a different tree with a limb 30 feet high. (Frankly, Glenn and I were amazed I could snag that limb.) This setup generated better a SWR reading – 1.61 at 7.040 MHz.

Now the true test – how well would I be heard?

the bench at which I operated Wednesday evening
RBN picking me up Wednesday evening

On Wednesday evenings, I check into the OMIK CW net. OMIK is a ham radio club founded in 1952 by “Black amateur radio operators from the states of Ohio, Michigan, Indiana, and Kentucky to deal with discrimination” at that time. Though the club membership today is primarily African-American, others like myself are welcome.

CW nets are a great place to get on-the-air experience with morse code. It was my code buddy Caryn KD2GUT who first introduced me to the OMIK net. I found those who participate in this CW net to be welcoming and accepting of CW operators of all levels of proficiency. Over the past several years, the ops in this net have watched my skills grow and become friends.

Dennis NT4U and Steve W0SJS split net control station (NCS) duties. This evening, it was Dennis’ turn as NCS. As he is located in northern Georgia, I figured he would hear my QRP signal. He did and checked me into the net with a RST of 589. The icing on the cake was that I heard a station he was unable to hear – Charles AI4OT in Virginia – due to the S9 noise at Dennis’ location this evening. I notified Dennis of Charles’ check in so he was added to the check-in list for that evening. Way to go homebrew linked dipole and Craig!

The next day, Glenn did some exploring and found a better location on the property – a hill behind the Airbnb and some sheds. Several large oaks in this relatively open area offered prime limbs to snag with an arbor line. I installed the antenna on a limb roughly 25 feet up in the air.

open area at back of Airbnb property
looking up into canopy at limb I used Thursday evening

Before attempting to check into another net, I spotted myself on QSO Finder, a new website and spotting tool by Mike N4FFF and Becky N4BKY of Ham Radio Duo. I had three exchanges, one each with Joel KE8WIC, Tom NG4S, and James KJ3D.

Spotting myself on CW QSO Finder

On Thursday evenings I check into the Sideswiper Net, a wonderful group of guys who meet on 40 or 30 meters (depending on propagation). Most of those who check in use a sideswiper (also known as a cootie) key but, like the OMIK CW net, they are welcoming of anyone who wants to participate no matter the level of proficiency or key. I’ve asked lots of questions of the members and appreciate their patience schooling me about CW nets.

The NCS this evening was Darrell AA7FV who is located in Arizona. The noise on 40 meters was rough but Darrel did copy me with a RST of 349. Two other stations – Bill WA4FAT in Alabama and Steve W1SFR – also copied me at 559 on this band.

When the net moved to 30 meters, my signal was worse. However, I expected that, as by this time it was dark and I didn’t want to mess with lowering the antenna to disconnect the link between the 40 and 30 meter wires. Darrel in Arizona could barely hear me (he gave me a RST of 129) but Bill could still copy me and acted as relay between our signals. I was thrilled that I had now checked into both nets QRP this week!

the RBN picked me up again

Even better, after the Sideswiper net, my code buddy Caryn KD2GUT and I were able to have our weekly code buddy QSO. We managed a 20 minute QSO on 40 meters before being swallowed up by noise and QRN on her end. Caryn is located on Long Island, NY. The previous night in the OMIK net, my signal was a 229 at her QTH. But tonight, we were both 599 and rocking it on the airwaves.

operating in the dark

During the Sideswiper net and my code buddy QSO, I sat head copying in the dark under the moon and thought, “It doesn’t get any better than this, right?”

Before we left the Airbnb Friday morning, Glenn spied several pitchforks sitting by the sheds. We picked one up and decided to have some fun, with our version of the famous piece “American Gothic” by Grant Wood. I had a difficult time keeping a straight face (watch the video linked down below) but eventually we got the shot.

“American Gothic” by Grant Wood    source: Wikipedia
us goofing off creating a version of the piece before checking out

QRP has its limits; however, I was sufficiently impressed by my experience on this trip that I will travel with a rig from now on. I’d like a better antenna and have ordered an EFHW as that is probably my best bet for a resonant antenna. This hobby NEVER becomes boring because there is always something to learn.

I look forward to trying the CFT1 and my new EFHW antenna when it arrives. How will that turn out? Stay tuned…

Equipment Used

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The POTA Babe Loses Weight

By Teri KO4WFP

I love living in the state of Georgia. The state contains diverse natural spaces – mountains and valleys in the north, rolling hills and forests in the middle, and a plain extending to the coast with wetlands, marshes, and forests.

source: Georgia DNR
source: GA DNR

The Georgia State Parks on the Air event celebrates and draws attention to state parks scattered throughout these spaces. For this year’s event (April 5th and 6th), I signed up to activate George L. Smith State Park (US-2179), a park located a little over an hour from my home. I’ve activated this park several times in the past – for POTA as well as the K2D special event.

To do something different and to qualify for the hike-in bonus (100 points) for the event, I planned to hike the Deer Run Trail. This trail runs past the historic mill on site and through a wooded area on the southeast corner of the park. To qualify for the bonus, I had to hike at least 1 mile from my vehicle so I walked a section of the outer loop trail.

water released under the mill on the lake
iris blooming

The hike was pleasant. Daisy and I walked through a forested area bordered by cypress bottomlands and farmland. Several benches along the path offered hikers a quiet place to relax. I was surprised by how many people we encountered.

the path leading from the mill – somewhere I’ve wanted to explore
the trail is well marked
a spot to relax on the trail

We finally reached the junction of the loop and .7 mile trail, the latter having a power line running along it. Here was another bench set admist a mixture of pines and hardwoods. A tall pine directly across from the bench had a branch about 30 feet high, just perfect for the dipole antenna I brought, that is if I could reach it.

the junction of the .7 mile trail and 3 mile loop trail
pine tree I spied for my dipole antenna

I removed my throw bag, arbor line, and throw weight, and tossed the line to see how close I could come to that branch. My line and weight ran over a broken branch forming a notch about 10 feet lower. I tugged to remove them and stared in amazement when the line abruptly broke free and fell at my feet…WITHOUT the weight attached. Oh crap! I was so gung-ho to nail that branch that I forgot to securely tie the weight to the line. (doh!)

my throw weight lodged in the notch

I stared in amazement, my mind slowly processing my situation. I did not bring an additional weight because I stopped carrying it since I never needed it (until now that is) and wanted to travel light for today’s hike. Shoot! Now what?

I spent the next 15 minutes trying to find a branch long enough to reach that spot as well as throw sticks at the weight. Nothing came close to dislodging it.

Well, I could just throw in the towel. But POTA Babes don’t give up that easily. I had an obligation to the event as I signed up to activate this park and hunters would be looking for me.

The only items in my pack I could attach to the arbor line and throw were an insect repellant bottle and my Nalgene water bottle. The insect repellant bottle I rejected because of its spray trigger which could definitely get stuck on a branch. But the Nalgene bottle might work. Daisy and I drank some water to lighten it. I tied the arbor line to the lid, found a branch about 15 feet up in the air, and tossed the bottle. Would this even work?

Nalgene bottle

It did! I know you antenna purists out there are shuddering. However, I figured a lower antenna was better than no antenna at this point. I brought two antennas with me for this activation: the Tufteln EFRW and a home-brew linked dipole I built roughly three years ago. A dipole is an amazing antenna, even if homebrewed. I figured my signal needed all the help it could get with the lower height and power lines nearby so I chose to use the dipole.

homebrew linked dipole antenna (40-30-20 meters)

Daisy and I settled across the trail in the understory to shade ourselves from the sun. One leg of the dipole ran across the hiking trail. To give the antenna as much help as I could, I secured both ends of the dipole roughly 6 feet up in foliage. Where it crossed the trail, it was high enough anyone would pass easily underneath it.

I took a breath, pressed the ATU button to activate the internal antenna tuner, cleared a frequency, and began calling CQ. I had no idea what to expect. Continue reading The POTA Babe Loses Weight

Construction Notes: VO1DR Monopod Antenna Mount

Many thanks to Scott (VO1DR) who shares the following guest post:


Construction Notes – VO1DR Antenna Mount for Camera Monopod

by Scott Schillereff,  VO1DR

Further to my article about radio during trip to Portugal, a number of readers asked for details on how I mounted my whip antenna system to my camera monopod for /P use.  Here are some photos and notes on this.

General notes:

  • This is a “straight-through” design.  Just direct connections from the BNC center pin to whip (via brass nut), and BNC housing to radial connector.
  • This is not a cook-book construction article, rather just a show-and-tell of how I built mine.  You can use what you have on hand to build something similar.
  • I suggest you start with your telescoping whip, so you know the size and threads for mounting bolt.
  • You could use any type of connector for the radial (wingnut, knurled nut, spade lug, alligator clip, whatever you like).  I prefer banana jacks since a) I can push in the radial banana plug fast, b) the plug is a weak release point (pulls apart if someone walks into the radial), and c) I can easily attach additional radial wires, if desired.
  • Use a strong case (metal clamshell or cast aluminum work well).  With the whip extended, there can be substantial forces (bending moment) from wind or handling. A tiny plastic case would be fractionally lighter but might fail.
  • For size, the one I used (25 x 25 x 50 mm; 1” x 1” x 2”) is about as small as I would go.  It needs to have a big enough footprint to sit firmly on a camera mount fitting.
  • Use high heat (e.g., Weller 100-140 W solder gun) when soldering the center pin wire to the brass whip mounting nut.  Solder the wire to the brass nut before you epoxy the nut.
  • I custom made the white plastic insulating bushing (where whip screws in). This was from a nearly-right bit from my junk box.  You can be creative here.  You could also epoxy on short piece of close-fitting, thick-walled PVC pipe around the outside of the whip mounting hole as a supporting sleeve to give some lateral support to whip when it is screwed in.
  • Dry-fit everything (before epoxying) to make sure nothing touches that shouldn’t and you can screw in the camera nut and whip fine.  Test proper continuity of center pin and radial connections to BNC fitting.  Once glued, there’s no going back!
  • For surfaces to be epoxied (metal nut sides and bottom, insides of mounting case), slightly roughen with sandpaper or jewellers file, then clean with isopropyl alcohol and Q-tip.  This will increase adhesion and strength.
  • Use good-quality, high-strength, long-cure epoxy (e.g., JB Weld), not el-cheapo 5-minute epoxy from the Dollar Store.  LET THE EPOXY COMPLETELY CURE BEFORE MESSING WITH IT!  Just walk away from it for a day… (your patience will be rewarded).

Figure 1 – VO1DR Antenna Mount, clamped onto top of monopod.  Coax goes to BNC on left; whip screws into top; raised radial connects by banana plug on right

Figure 2 – Antenna mount unclamped from top of monopod.  The black plastic fitting (at right, with wedge-shape) fits into slot on platform at top of monopod (at left) and clamps in with cam arm.  Large steel screw attaches wedge fitting to antenna mount case. Ruler shows scale of things.

Figure 3 – Antenna mount case (right) unscrewed from camera mount fitting.  Steel screw is standard camera mount size (1/4-20 thread size).  Black silicone cap keeps dust out of BNC connector.  If your camera mount does not have a detachable wedge fitting (like the one on the left), you would simply screw the camera mount screw directly into the bottom of the antenna mount case.

Figure 4 – Top of monopod dissembled to show (clockwise from top): black monopod tube with telescoping whip stored inside (stainless steel with 10 mm brass mounting bolt), antenna mount case, detachable camera mount fitting, and round top plate of monopod.  For my monopod, I had to remove one tiny screw and apply gentle torque to break a weak glue joint of this round piece on top of the monopod leg.  It remains a snug hand fit (no screw needed).

Figure 5 – Fully assembled whip antenna mount with wiring.  Radial (blue wire) with tie-off cord (yellow) at left; RG174 coax (5 m) at right.  Whip is only ever screwed in hand-tight.  Deploying in the field, I first tie off the monopod to something (park bench, picnic table, fence, tree), then screw the collapsed whip into the antenna mount and clamp mount on top of monopod, then plug in radial and tie the yellow cord off to something (straight out at 2 m height or slope down to ground anchor), and finally connect the coax to the rig.  When all in place, I carefully raise the whip (slowly, with two hands to reduce bending forces).  Take-down is all in reverse.

Figure 6 – Detail of antenna mount case.  Case is 50 mm x 25 mm x 25 mm aluminum clam shell box with square metal end plates.  These end plates are screwed in to hold the two halves together.  White plastic bushing provides additional lateral support for the whip when it is screwed in.  The bushing is glued to outside of case with CA (Krazy) glue.

Figure 7 – Inside of antenna mount case.  On left, a ¼-20 steel nut is epoxied to inside of case with strong JB Weld epoxy.  In main case, a 10 mm brass nut is epoxied to inside of case with an insulating washer beneath.  This brass nut connects to the whip and is “hot”, so must be insulated from the black aluminum case.  Yellow wire connects center of BNC to brass nut (soldered).  Black wire connects ground side of BNC to radial banana jack.  Use plenty of epoxy; there is a lot of force exerted on the steel and brass nuts.

Figure 8 – Detail of inside of case.  Note separation of banana jack solder post and edge of 10 mm brass nut.  Solder yellow wire to nut before epoxying in nut.

Hope you find this useful.  Just use what you have on hand and some ingenuity to make yours!

Best 72, Scott  VO1DR

Sam builds a tiny tabletop HF antenna

Many thanks to Sam Duwe (WN5C) who shares the following guest post:


A (surprisingly good) tabletop HF antenna

by Sam Duwe, WN5C

I recently built a tabletop QRP HF antenna for 17 and 20 meters, in the spirit of the Elecraft AX-1, so I could operate at lunchtime on the campus where I teach. My wants were something small, that would fit in my work bag, that didn’t require a tuner, and could work on a couple of different bands. But on a lark I decided to attempt a POTA activation at Lake Thunderbird State Park (K-2792) pairing this antenna with my Penntek TR-35 QRP CW transceiver. I figured I’d maybe get one or two QSOs and then switch to a long wire in a tree. But what happened amazed me.

I talked to seemingly everyone. Beginning at 9:00 AM September 26th I worked both 17 and 20 meters for an hour and a half and made 37 contacts from across the country. I even had a Swiss guy call me back on 17 but he faded before we could finish. This antenna, at least as a CW POTA activator, works. Granted conditions were very good, but I’ve replicated this multiple times in the past few weeks, just recently at a picnic table in the parking lot of the Route 66 Museum (K-8644) in Clinton, OK (there is quite a thrill in urban activations).

It has also reasonably low profile and very quick to setup and take down. It is also quite a conversation piece when I set it up at school. I elevated the counterpoise by attaching it to a nearby oak and an interested undergrad sheepishly asked if I was listening to the tree!

The build is pretty simple. Physically the antenna consists of a small painters pole from Walmart and an old tabletop camera tripod. I found a nut that fit the screw portion of the tripod and hot glued it into the orange connecting section of the pole. That way the tripod can then be screwed onto the pole. The RF parts of the antenna consist of a 38” telescoping whip that I scavenged from the rabbit ears antenna that came with my RTL-SDR. It connects using the original connector which was hot-glued into a hole I drilled into the top of the painters pole. I found similar small 3 or 4-foot whips from AliExpress for cheap and these would probably work fine.

I then soldered a long length of speaker wire that was wound into two coils: the top for 17 meters (24 turns) and the bottom for 20 meters (25 turns plus the former 24-turn coil). The speaker wire was the soldered to the center of a BNC connector which I hot glued and taped to the pole. I soldered a short piece of wire from the shield of the BNC for the counterpoise and added an automotive spade connector to attach to a 17-foot length of wire. I also included a switch between the coils and the BNC connector to select either just the top coil (17 meters) or both coils (20 meters) using solder, hot glue, and tape.  I then covered my shame in silicone tape.

The most time-consuming aspect of the project was tuning the antenna. It required trial and error to first tune the number of turns on the 17-meter coil and then the 20-meters coil. I extended the counterpoise (for me it’s best when slightly elevated) and the telescoping whip. I performed the tuning with the whip not fully extended to give room to tune in the field. Using a nanoVNA was useful here, as was soldering a pin to the wire to poke through the wire at various parts of the coil to find the best SWR.

In use, the antenna can be affected by both body capacitance and how the counterpoise is situated, so I found that an in-line SWR meter was helpful in making sure all was well. Once set up it is easy to fine tune by just adjusting the whip length. 1.5:1 SWR is about how well I can tune on average. Obviously if you have a tuner you would just have to get it close.

There are a million variation on a small base-loaded vertical antenna, and you can definitely improve upon this design. And, besides the super well-built and elegant AX-1, QRP Guys sells an interesting looking kit, and there are some good 3D printed designs I might want to try out. But regardless how you go about it, it might be worth giving a tiny antenna a shot.

72, Sam WN5C

Steve’s Homebrew Vertical Antenna for POTA

Many thanks to Steve (KM4FLF/VA3FLF) for sharing the following guest post:


A Great Homebrew Vertical Antenna

by Steve (KM4FLF/VA3FLF)

Last spring, I was going through my many boxes of ham “stuff” looking for items to sell at our club tail gate sale. I came across a couple of Hustler SM Series Resonators (20 /40 Meters) that I had acquired. I am not sure where I obtained them, but I decided they were keepers.  That decision turned out to be the first step in a year long process that has given me an awesome homebrew vertical antenna.

After doing a little research I found the resonators and accessories at most of the online ham dealers. They are used primarily as mobile and marine antennas. I had seen where a ham had used these on a ground stake as a portable antenna as well. I ordered a Hustler MO1 mast which is 54 inches tall and thought I would attempt to make a portable POTA antenna.

Antenna base

I had a couple of small aluminum plates that I drilled out a few holes. I cut out a notch to put a SO-239 Stud Mount on the plate as my antenna base. I now had a ground plate, connector, and antenna with resonator. By putting a stake in the bottom of the plate, I was able to get the antenna to stand up. The Hustler resonators have a hex screw for tuning that can be loosened. The antenna can be adjusted for resonance by lengthening or shortening the radiator length. After adjusting the radiator my SWR was still horrible on the two bands.

Antenna base close-up

I had some 14-gauge wire laying around and attached it to the plate using carriage bolts and nuts for my ground radials. I didn’t think about the length of the wires at this point but went with three or four lines around 20 to 30 ft. I was able to use my vertical a few times with moderate success. My SWR on 20 and 40 Meters was around 2:0 to 1 at best. It was bulky and very delicate. Sometimes screwing in or unscrewing the MO1 the SO239 would slide off the edge of the aluminum plate. I put away my contraption for the winter and decided to move on to something else.

In April of this year, I wanted to revisit my project. Continue reading Steve’s Homebrew Vertical Antenna for POTA

Dan’s clever chalk line homebrew EFHW antenna

Many thanks to Dan (KQ8Q) who writes:

Hi Tom,

I discovered something you might have an interest in for your wire antenna deployment. Years ago when I was a building contractor, we used chalk line for floor layout. It has a very high tensile strength and is very light weight. After reflecting on this, I recently bought a 100’ spool of braided 1 millimeter chalk line and used it for a field deployment. I attached my “throw weight” to it and easily launched it about 60’ into a tree. You can see it in the attached photo holding my homebrew EFHW to my Jeep.

This link is what I used: Tajima PL-ITOL 100 ft .04″ Bold Braided Replacement Chalk Line New | eBay

Click here for full parts list (PDF)

The magnet wire was scavenged from a HUGE transformer from a neighbor’s discarded light fixture.

Lug Nut Throw Weight: left hand threaded from a 1966 Plymouth Fury

I did the new installation for him and he gave me the old one. I promptly disassembled it and collected miles of 14 and 20 gauge magnet wire ?!

I haven’t added the capacitor to this antenna yet because it is sufficiently resonant and broadbanded on 40, 20, 15, and 10 Meters. I did some testing with the capacitors though on my previous build which was the PVC tube EFHW transformer. I believe I may have sent you a photo of that in a previous message. It too was resonant in the same places, but adding the capacitor smoothed and widened the acceptable SWR range.

The attached photos are my complete antenna assembly: matching transformer (49:1), 65.5’ speaker wire, 100’ braided 1MM chalk line, and throw weight (epoxy filled lug nut with short paracord pigtail).

Compact and lightweight.

Dan/ KQ8Q

I love this, Dan! I also like how self-contained and compact it is. What a professional job, too, with heat shrink, proper connection points and tie-offs.

Brilliant work!

Do you have an antenna or radio project you’d like to share on QRPer.com? Contact me!

Field Report: Let’s build a super simple antenna on-site and activate this park!

Until 2016, I had never purchased a commercial field antenna; I built all the ones I had ever used.

These days, I take a number of commercial antennas to the field and use them in my real-time videos and I really enjoy deploying and using them. My buddy Eric (WD8RIF) reminded me, though, that I hadn’t actually used a homebrew antenna in ages. He was right!

You see, while I believe commercial field antennas can be incredibly durable and compact, it’s important to note that antennas are one of the easiest components of an amateur radio system to build yourself. They require only the most simple of tools and are very affordable. And the best part? They can perform as well as those that are available commercially.

I also get a great deal of pleasure out of building things.

A simple goal

I’ve mentioned in previous posts that I often set a little goal that runs in the back of my mind for each park or summit activation I make.

On Monday, June 14, 2021, I made a simple goal: buy my antenna wire en route to Lake James State Park, build the antenna on site, and complete a valid Parks On The Air (POTA) activation.

A very simple antenna

I also decided to employ my Xiegu X5105 since 1.) it’s one of the most affordable general coverage QRP transceivers I own and 2.) it has a built-in antenna tuner (ATU).

One of the cool things about having an ATU is that, if it has the matching range, you can allow it to do the “heavy lifting” in terms of matching impedance.

Although I’d never put the X5105 to the test, I suspected its internal ATU would have the matching range to forgo building a 4:1 or 9:1 transformer and simply pair it directly with a random wire.

All I would need was a 28.5 foot length of wire for a radiator, at least a 17 foot length for a counterpoise, and a BNC to binding post adapter.

The antenna would benefit from multiple 17′ counterpoises, but I really wanted to keep this setup dead simple to prove that anyone can build an effective field antenna with a very minimum amount of components.

Even though I have plenty of wire lying around the house to build this simple antenna, I wanted to pretend I had none to prove that any wire would work.

And to add just a wee bit more challenge, I also limited myself to shopping for antenna wire between my home and the park without making a serious detour from my route. That really limited my options because there isn’t much in terms of commercial areas between me and Lake James State Park.

The wire

As I left the QTH, I decided that the best spot to shop was a Walmart in Marion, NC. It would only be a four minute round-trip detour at most.  I had a hunch that Walmart would even have speaker wire which would be ideal for this application.

In my head, I imagined I would have at least three or four choices in speaker wire (various gauges and lengths), but turns out I had a difficult time finding some at Walmart. We live in such a Bluetooth world, I suppose there isn’t much demand for it these days. A store associate helped me find the only speaker wire they had which was basically a 100 foot roll of the “premium” stuff for $17 US.

While I would like to have paid a fraction of that, in the end it’s not a bad price because once you separate the two conductors, you have double the amount of wire: 200 feet.

Although the frugal guy in me cringed, I bit the bullet and purchased their speaker wire. To be clear, though, I could have found another source of wire in that Walmart, but I preferred speaker wire for this application. And $17 to (hopefully!) prove a point? That’s a deal! 🙂

Lake James State Park (K-2739)

Once I arrived on site, I found a picnic site I’d used before with some tall trees around it.

Here’s how I prepared the antenna:

First, I cut 28.5 feet of the speaker wire from the roll and split the paired wires so that I’d have two full 28.5 foot lengths.

Next, I stripped the ends of the wire and attached banana jacks I found in my junk drawer. Although these aren’t necessary as the binding post adapter can pair directly with the wire, I though it might make for a cleaner install. In the end, though, I wasn’t pleased with the connection to the radiator, so dispensed with one of the banana jacks on site, and later dispensed with the other one as well. The connection is actually stronger without the banana jacks.

I then deployed the 28.5 radiator with my arborist throw line, and laid the other 28.5 half on the ground (the ground of this antenna would pair with the black binding post, the radiator with the red post).  I only needed 17 feet of counterpoise, but once it couples with the ground, I don’t think any extra length makes a difference (although less than 17 feet likely would).

The antenna was essentially set up as a vertical random wire with one counterpoise.

I then plugged the BNC binding post adapter into the rig, hit the ATU button, and was on the air.

It’s that simple!

My new speaker wire antenna in all its glory.

Gear:

On The Air

I’ll admit: I was a bit nervous putting this antenna on the air. Although I felt the X5105 ATU *should* match this antenna, I had no idea if it actually would.

Fortunately? It did.

At this point, if you don’t want any spoilers, I suggest you watch my real-time, real-life, no-edit, no-ad, video of the entire activation (including buying and building the antenna!).

Click here to watch the video.

Otherwise, scroll for my activation summary…

I was very pleased that the X5105 found a match on the 40 meter band.

I started calling CQ in CW and validated my activation by logging 10 stations in 13 minutes.

Honestly: it doesn’t get much better than this.

I logged three more stations on 40 meters CW, then moved up to the 30 meter band where the X5105 easily found a match.

I worked one station on 30 meters before heading back down to the 40 meter band to do a little SSB. I logged three SSB stations in five minutes.

Mission accomplished!

In the end, I logged a total of 17 stations including a P2P with K4NYM.

Not bad at all for speaker wire!

After the activation, I tested the X5105 ATU by trying to find matches on other bands–I was able to find great matches from 60 meters to 6 meters. Most impressive!

X5105 battery

You might recall that I attempted to deplete my X5105 internal battery at my last (rather long) activation of Lake Norman State Park.  I wasn’t able to deplete the battery at that activation, but I finally did at this one.

All I can say is that I’m incredibly impressed with the X5105 internal battery.  This was my fourth activation from one initial charge on May 16.  The battery lasted for 20 minutes, taking me well beyond the 10 contacts needed to validate this park. I’ll now consider taking the X5105 on a multiple SOTA summit run!

Short Hike

Even thought the heat was intense and the humidity even more intense, I decided to take in a 2 mile hike post-activation. I snapped a few shots along the way.

This is the Christmas Fern which derives its name from a few characteristics: its resilience to early season snows maintaining a dark green color beyond Christmas, and because folks believe its leaves are shaped like Santa’s boots or even Santa on his sleigh.

Improvements

I’ll plan to add more counterpoises to the speaker wire antenna as I know this will only help efficiency.

In addition, I’ll plan to build even more antennas with this roll of speaker wire. If you have some suggestions, feel free to comment!

Thank you for reading this field report!

Cheers,

Thomas (K4SWL)


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