All posts by Thomas Witherspoon

Antennas, Articles, Guest Posts, News

Chameleon MPAS Lite: Using the coax shield as a counterpoise and how this might affect directionality

9 Comments

Many thanks to Dale (N3HXZ) who shares the following guest post:

Portable Operation Using a Vertical Antenna Without a Counterpoise Wire!

by Dale (N3HXZ)

In a previous article that Thomas was kind enough to post, I ran experiments to determine if the counterpoise wire orientation of the Chameleon MPAS LITE antenna system in the vertical configuration in any way shaped the antenna pattern.  The configuration of the antenna is shown below.

The system consists of a 17’ telescoping whip antenna, a matching transformer, a 50’ coax cable with an in-line RF choke, and a counterpoise wire (60’ long, but unwound to only 25’ for use in the vertical configuration).

Subsequent studies I performed have reinforced my earlier conclusions that the positioning of the counterpoise wire in this setup does not appreciably shape the antenna pattern. One of the comments from my post came from Stephan (HB9EA). He commented on the fact that the coax cable is indeed a counterpoise via the coax shield and that in fact my system set-up had two counterpoises.

It was Stephan’s comment which led me to contact Chameleon Antenna to discuss counterpoises with the MPAS LITE antenna in the vertical configuration. I communicated with the Director of Research and Development group at Chameleon and found out some interesting information that I wanted to pass on.

He mentioned that the system can be used with the coax cable acting as the lone counterpoise as long as the coax cable is at least 25’ long, and preferably 50’ long.  The coax should be spread out and not coiled along any portion of its length. It was stated that the counterpoise wire provided with the product should be used with short-length coax cables.

With regards to a counterpoise orientation shaping the propagation direction, he stated that it is generally accepted that using only the coax as a counterpoise tends to have the antenna pattern slightly favor the direction in which the coax is laid out. Adding the counterpoise wire in a direction opposite to the coax would tend to balance out that pattern. Having the coax and counterpoise wire at some angle to each other introduces variables that make it difficult to determine the antenna pattern.

My initial study had the counterpoise wire oriented at an angle to the coax cable.  I mentioned that my initial study showed that orientation of the counterpoise wire did not seem to appreciably shape the antenna pattern, and he agreed. What is unknown is the overall degree to which the coax cable shapes the antenna pattern with or without use of the counterpoise wire.  This is an area I am currently investigating.

Operating the MPAS-LITE vertical configuration with only the coax cable as a counterpoise was an intriguing thought.

To test it out I teamed up with Jim (KJ3D) for a SOTA activation on W3/PT-003 (Seven Springs). We both deployed the MPAS-Lite with only the supplied 50’ coax cable attached. Coax cables were laid out in a straight line. One cable was oriented southeast, the other one oriented east. We operated on 10 Watts in CW mode. The activation successfully worked all bands from 40M to 10M. I operated an Elecraft KX2 and Jim operated a KX3. The internal tuner of both rigs easily obtained a 1:1 match across all bands.

A map of the QSO’s is shown below. Note that despite the coax cables facing to the southeast and east, we easily worked stations in the opposite directions. Hence any minor shaping of the antenna pattern by the coax orientation does not appear to impede successful communication in all directions.

In summary, the MPAS-LITE antenna system in the vertical configuration utilizing the 50’ coax cable with an in-line RF choke as the single counterpoise has been demonstrated to perform well in the field.

For portable operation where fast deployment and simplicity is paramount, using the furnished coax as a counterpoise is a quick and dirty way to get the antenna erected and on the air with reliable communication capability. Eliminating the counterpoise wire allows for quicker set-up and tear-down, and one less thing to put in the backpack!

Field Radio Kits, Guest Posts, News, QRP

Field Kit Gallery: N8PEM’s MTR-3 Portable Field Radio Kit

12 Comments

Many thanks to Chris (N8PEM) who shares the following article about his portable field radio kit which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, check out this post.

MTR-3 Field Kit Build by N8PEM

Ham radio is a hobby best enjoyed in community with others.

Ever since I began operating QRP portable a few years back I had admired the Mountain Toppers.  Granted my Elecraft KX2 is a perfect daily driver.  I’ve been lucky to have that as my sole portable QRP rig for some time.  That didn’t stop me from dreaming of an ultralight QRP portable kit centered on an MTR3.  High resale prices and scarcity made it a purchase I had long put on the back burner.  But then one day I saw my good friend Julia, KF8JBB, while walking my dog in the park.  So I stopped to chat.

Figure 1:  Antenna Design

Like many of us, Julia is an avid QRP and CW enthusiast.  She has numerous QRP and SWL radios.  Life is also pretty busy for her.  She doesn’t get out to operate as much as she would like.  As we chatted on that warm August evening, she offered to gift me her MTR3.  For her, it was time to move that rig on to a good home so it would get it’s proper use.  But the shrewd negotiator in me knew to never accept a first offer.  I countered.  I’d take the MTR3 off her hands if she let me build her a QRP portable antenna in return (later I also threw in a built N6ARA TinySWR kit for good measure).  She accepted.  The next day she dropped off the rig.  The fun of outfitting an ultralight (UL) QRP kit began.

I quickly determined that I wanted to build a trapped 20/30/40 meter EFHW antenna to match the three bands on the Mountain Topper.  I prefer end feds, and I wanted the challenge of building traps for the first time.  Keeping in mind I wanted an UL kit, I could also leave the coax at home with an end fed.  I had read that a trapped EFHW can be shorter than a standard EFHW due to the inductance of the traps.  This appealed to me as I knew from experience that getting a 40-ish foot antenna up in the air is much easier than a 60-ish foot antenna.  It took nearly six weeks to research, procure parts and build out this antenna, partly due to the fact I had to build this antenna twice.

My first attempt at this antenna build wasn’t good.  I couldn’t get SWR better than about 1.8:1 on any band.  I hadn’t tested every component at every step of the build.  Thus, I had a hard time determining what went wrong.  I used 100 and 150 pF capacitors for the traps which proved to have marginal shortening effects.  I needed more turns on the toroids!  I decided to do more research and start over.

Thanks to advice and blogs from folks like Dan AI6XG and Fred KT5X, I settled on a different, better design of the trapped EFHW.  I ordered more parts.  Switched out to 15 and 33 pF capacitors.  I took my time to build and test this antenna in a step by step manner.  The results were much better the second time around.  Overall 45 feet 8 inches long and weighing two ounces.  SWR better than 1.5 to 1 on all three bands.

I had the idea to place a TinySWR kit in line between the RCA plug and the end fed matching unit.  I know there are SWR kits which can be installed within the radio, but I didn’t want to modify the MTR3 in any way.  The stock design is sublime.  I also built a back-up emergency antenna into the design.  If for some reason I have a trap fail, I installed a bullet connector right before the first trap.  Thus, I can disconnect the 30 and 40 meter portions of the antenna and  have a basic resonant 20M EFHW.  These thoughtful touches seemed to perfect the antenna.

Photo 1:  Completed miniSWR, matching unit, 30m trap, and 20m quick disconnect

I tried to be thoughtful with the other choices in my kit as well.  At 3.5 ounces and the size of a bag of coffee, the LowePro CS40 padded case proved to be ideal.  I found it cheapest from a UK-based eBay seller.  I made my flight deck out of the steel housing from an old external CD Drive.  I measured, cut and filed the edges.  It’s perfectly sized for loose Rite in the Rain paper, lightweight and thin.  A metal flight deck also can hold the magnetic base of my CW paddles.  When it came to the battery, I decided to go with a RC airplane LiPo battery.  Fuzzy math told me that the 650 mAh would give me more than enough operating time.  Once complete, I was happy to find the entire kit weighed in at just 18 ounces, not counting a throw weight or collapsable mast.

Photo 2:  The completed MTR3 kit

My first activation with this kit was September 21st.  I wasn’t sure how well I would do.  Band conditions weren’t the best the previous two days.  I went to my favorite spot, Bunker Hill (W8O/SE-009) located within Great Seal State Park (K-1954) in south central Ohio.  It’s a short 20 minute hike to the high point on what was a partly cloudy 70 degree Thursday morning.  I set the antenna up in a sloper configuration, gave my dog Togo some treats, ate half my sandwich, took a sip of coffee, and pulled up the POTA and SOTA spotting pages.

In just over an hour I had made 54 QSOs covering all 3 bands.  The MTR3 combined with the trapped 20/30/40 EFHW worked flawlessly.  It was an absolute joy to operate.

Photo 3:  First activation complete

That joy came from the sublime kit for sure.  But enjoyment also came from the community carried within the kit itself.  The MTR3 from Julia KF8JBB.  The paddle and wire winder designs from Adam K6ARK. The MiniSWR Kit from Ara N6ARA.  The Trap PCB boards from Tim N7KOM.  The toroids, capacitors, and antenna advice from Dan AI6XG.  The blog post from Fred KT5X.  The 3D printing from my nephew Colin.  Even the RigExpert I bought from Glen W1ND this Spring was integral.  This kit is an homage to that community.

Figure 2:  First Activation QSO Map

If you made it to the end, thanks for reading!  I hope it was interesting and helpful.

TU 73 EE,

Chris N8PEM

Radio Kit

Antenna Build

Field Reports, News, Portable, QRP, SOTA

A beautiful (and hot) day for a QRP SOTA activation on Bearwallow Mountain!

8 Comments

Tuesday, September 5, 2023, was a gorgeous day. A hot day, but a beautiful one!

I couldn’t pass up the opportunity to fit in a quick SOTA activation and the most accessible summit that day was Bearwallow Mountain.

Bearwallow Mountain (W4C/CM-068)

I was in South Asheville all day, so Bearwallow was only about a 25 minute detour.

Since it was a Tuesday in the latter part of the morning, there were few others parked at the trailhead. Had it been a Friday, Saturday, or Sunday? It can be difficult to find a parking spot. Indeed, the previous day (Labor Day) I’m sure it was packed!

I practically had the place to myself, though.

The hike up was most enjoyable although it was hot and humid, so sweaty I became.

That said–and I think I even say this in the activation video below–I really wished the hike was a bit longer. The Bearwallow trail is maybe a mile long.

I wanted a longer hike, but in truth, didn’t have the time for one anyway.

Bearwallow’s summit is a large pasture. It does offer up some spectacular long-range views.

Bearwallow is also home to a lot of comms towers including a number of local repeaters.

I found a nice, flat rock, set up my chair, and deployed my Chelegance MC-750 vertical. Continue reading A beautiful (and hot) day for a QRP SOTA activation on Bearwallow Mountain! →

Antennas, Field Radio Kits, News, Portable, POTA, QRP, SOTA

I’m in portable field radio kit mode…how about you? Care to share?

16 Comments


A portable field kit:  it’s a seasonal thing.

In the early fall and spring, I go over my QRP radios and give serious thought to how I’ll build compact field kits around them.

Why? I’m pretty sure it’s the pending change in weather that’s the catalyst.  The temptation to get back out there and make some contacts.

Then again, any excuse:  I absolutely love building field kits, and fortunately it never gets old.

The radios I’m considering at present are my MTR-3B (named Threepence) and KX1, now named Audrey. (Yep, I chose “Audrey”…thank you for all of the amazing suggestions!)

Both of these are ideal little radios for kitting out because they’re so compact and truly made to be taken to the field.

One of these two radios––and I haven’t decided which one yet––is going to live in my EDC bag.

The Tom Bihn Stowaway in black has been my EDC bag for many years. I’ll need to pay attention to the weight and bulk of this field kit, because I’ll be lugging it pretty much everywhere.

I’ve got some ideas and a couple of pouches in mind, so this will all start coming together soon.

But first…

Care to share your portable radio kit?

One of the things I enjoy doing when I’m putting together a new field kit is to check out what others have done.  It’s a great way to get some fresh ideas…and besides, it’s  just plain fun to compare notes.

If you would like to showcase your field radio kit on QRPer.com, please send a short write-up with photos detailing how/why you built your kit as you did, and list all of the components with links to the manufacturers.

We’ll not only publish your field kit article as a post, but also on this new Field Radio Kit Gallery page I created!

We only ask that you send your own original ideas––and not just a link to another website article or video––as we’d like this content to become part of the QRPer archive. That way, if an external link is removed, it’ll still be safe and sound here. (We take our archiving seriously on this site.) Of course, we welcome links to blog articles and videos in your post.

Simply send your information via email to my callsign K4SWL at QRPer.com.

Interested? Feel free to get in touch!

Field Reports, News, Portable, POTA, QRP, QRPp, Videos

One Watt, Low-Profile QRP: A Labor Day POTA Activation at Lake James State Park

7 Comments

I realize that I’m fortunate, in many ways, that I perform POTA activations at times when parks are relatively quiet: weekdays, mostly, and during that 9-5 window when many are at work. On the flip side, I’m also activating when there are fewer hunters out there.

The upshot, for me, is that I rarely have any competition for picnic tables or activation spots at state and national parks. In general, as you’ll see in my activation videos, the park is quiet and sometimes I literally have the place to myself.

I actually take this for granted until I activate on a busy weekend or a holiday. Something like…

Labor Day!

While traveling back to the QTH on Monday, September 4, 2023, I decided to pop by Lake James State Park (K-2739) for a quick POTA activation.

Lake James State Park spans about 3,743 acres and is divided into two areas: the Catawba River Access and Paddy’s Creek Area.

Typically, I play radio at the smaller Catawba River area because there are so many excellent picnic sites with loads of trees.

The Paddy’s Creek area is much larger and (big bonus) has many more trails.

Paddy’s Creek also has a large beach and swimming/boating area with a huge parking lot and large covered picnic shelter (that is often occupied or reserved).

On Labor Day, the weather was gorgeous and, as you might imagine, the park was packed!

So why did I choose Paddy’s Creek on such a busy day?

I might have mentioned in a previous video that we recently purchased a used Volvo C40 Recharge EV (Electric Vehicle). While I normally charge it up at home, I’m trying to familiarize myself with charging on the go as well.

I’d read that Lake James has two (free!) convenience chargers at the Paddy’s Creek area. I drove to the site mainly to see where the were located. On such a busy day, I didn’t assume either of the chargers would be available–my plan was to find them, then head to the Catawba River access.

But turns out, the only available parking spot I could find at the Paddy’s Creek lot was one EV charging spot right there at the beach access and shelter! What!?! That’s an omen, I told myself, so I pulled into the spot, plugged in, and by golly, the car started charging.

I’m still new at this stuff, so it’s all a bit of magic to me. Forgive my excitement.

But where to activate?

The park was teeming with people all out enjoying the weather, the water, and the food and drinks. Truth is, I love seeing parks being enjoyed on this scale. Continue reading One Watt, Low-Profile QRP: A Labor Day POTA Activation at Lake James State Park →

New Products, News, QRP Radios

Two more images of the new Xiegu DDC/DUC portable transceiver

8 Comments

Many thanks to Don (W7SSB) who shares the following two product images/teasers courtesy of Xiegu (click images to enlarge):

Thanks for sharing these, Don, as a follow-up to our previous post.

Xiegu fans will be happy to see that this new transceiver has a removable battery pack. If this pack is easy to source/obtain, that will indeed be a strong point.

It looks like Xiegu has also added fixed rails to protect the front panel along with reinforcement around the chassis.

It looks quite durable, although it also appears there are two knobs protruding on the top of the radio–?

On our previous post, there were a number of skeptical comments about the new Xiegu transceiver. Indeed, some of the comments were from X6100 owners who feel that Xiegu hasn’t fully completed all of the published features promised in the ‘6100 (which was released two years ago). A number of owners also commented that getting support or repair work done after the one year warranty has challenging. These are, for sure, some of the risks associated with price-competitive radios. Xiegu radios offer a lot of features for the price.

After this radio new is released, I will reach out to Xiegu or Radioddity and ask for a loaner to test in the field. I’ll be very interested to know if it has a few of these improvements over previous models:

  • Better front end with some built-in BCI filtering
  • Cleaner audio with balanced AGC
  • Lower noise floor
  • Longer battery life than the X6100
  • Published features which actually work in the first production run

I haven’t gotten a confirmation of the price or availability yet.

Stay tuned!

Field Reports, News, Portable, POTA, QRP, QRP Radios, Videos

QRP POTA: Breaking in an Elecraft KX1 and setting up message memories in the field

21 Comments

If you’ve been reading QRPer.com for long, you’ll no doubt have gathered that I’m [understatement alert] a big fan of the Elecraft KX1.

A couple months ago, a good friend and supporter of this site/channel, reached out to me because he planned to sell his pristine Elecraft KX1. He’s in the process of downsizing his radio inventory in preparation of a move.

He wanted me to have first dibs at his KX1 and I couldn’t refuse. I knew it would be a great unit and I wanted two fully-functioning KX1s.

You might ask, “But wait Thomas, don’t you have three KX1s???”

Yes, this is true.

With this latest addition, I have now have two fully-functioning KX1s (a 3 and a 4 band version) and one other in need of repair. After I make the repair, I plan to give this radio to a friend (one who doesn’t read QRPer regularly) so will be back to two KX1s.

Since Elecraft has discontinued the KX1, they’ve become difficult to find on the market and when they do appear, they often demand a very high price.

That said, if you’ve been looking for a KX1, you will eventually find one. All of my friends who’ve wanted one have put out word and found willing sellers in due time. Elecraft sold quite a few of these back in the day, so there are units floating around out there.

Tuttle Educational State Forest (K-4861)

On Sunday, August 27, 2023, I had an opening to play a little radio and fit in a hike at Tuttle Educational State Forest.

At the time, I needed a little radio therapy and outdoor break: my mom had been admitted to the hospital the previous day (they released her a few days later and at time of posting she’s doing much better).

Tuttle was only a 30 minute drive from the hospital and, as I suspected, I was the only visitor there that Sunday–educational forests aren’t nearly as busy as other NC state parks.

After a nice 3-ish mile hike, I grabbed my radio backpack from the car and started recording an activation video.

My goal was to test this new KX1 and to set up CW message memories.

First, though, I needed to deploy an antenna. I chose my MM0OPX EFHW because it was in my pack from a previous activation. This antenna has never let me down. Continue reading QRP POTA: Breaking in an Elecraft KX1 and setting up message memories in the field →

News, QRP

The New Brooklyn QRP Doghouse Operation Sprint 2023: November 18, 2023

Leave a comment

Many thanks to Kevin (N2TO) who shares the following announcement:

 

Announcing the Brooklyn QRP Doghouse Operation Sprint 2023

I would like to thank Thomas K4SWL and offer my congratulations for induction into the ARCI QRP Hall of Fame! Well done!

Here is a sprint you can work and stay out of the doghouse on the Saturday afternoon prior to Thanksgiving. Play radio, and have plenty of time to mow the lawn, shovel snow, clean the guest room; do whatever it takes to get ready for Thanksgiving.

This is a single-op QRP CW sprint. Stations may be worked more than once on different bands but area codes count once.

Date: Saturday, November 18, 2023
Time: 1700-2100 UTC

Information can be found here: https://brooklynqrp.blogspot.com/ If you would like to operate the sprint please email [email protected] as we are trying to drum up interest. Results will be posted after Christmas. We hope to hear QRP CW activity on November 18th and have a great sprint.

72 Kevin N2TO

Field Reports, Guest Posts, News, Portable, POTA, QRP, Travel

Bob’s POTA weekend in eastern North Carolina

5 Comments

Many thanks to Bob Conder (K4RLC) who shares the following guest post:

North Carolina Parks On The Air Activation weekend

Bob (K4RLC)

The first North Carolina Parks On The Air Activation weekend occurred September 9 & 10. Between a limited amount of time available and weather, I only was able to activate three parks, including an over-night camp out. The primary goal was to return to the Dismal Swamp State Park (K-2727) in Camden County. While the Dismal Swamp in Camden County is a rare and sought after County on CW for those wanting to work all 100 North Carolina counties and all 3000+ US counties,  it also is a place comforting to my tortured soul.

As there is no camping at Dismal Swamp State Park, one camps at the nearby Merchant Mill Pond State Park (K-2745)  in Gates County. This is a pleasant small State Park with canoeing and fishing in a 190 year old millpond, with old-growth Cypress trees. It is near the lower extension of the larger Dismal Swamp National Wildlife Refuge, which begins in Virginia.

As an older park, Merchants Mill Pond SP does not have any hook-ups for water or electricity. Fortunately, I was camping in our Solis campervan, which is self-contained by solar power and good for boondocking.

The oppressive heat gave way to rain, so I set up inside the van at my campsite. This gave me an opportunity to use my new favorite portable radio, the Penntek TR – 45 Lite, a QRP CW only radio. An outstanding feature of this rig is that it has no menus, only knobs and toggle switches, and reminds me very much of my radios from the early 1960s, but with modern specs.

The internal keyer performed well with the Putikeeg magnetic paddle from Amazon. Even though there was distant thunder, I felt it was safe to set up an inverted V on a fiberglass mast, bungee-corded  to a trailer mount hitch on the camper van. I ran the RG-174 coax through a rear window by sliding the window screen open a bit.

Not wanting to invite an onslaught of mosquitoes, I only used red lights inside the Solis, reminiscent of military operations. The TR -45 Lite did well on 40 CW with 5 W and the inverted V in the rain, and no mosquitoes invaded the van.

The overall goal was to return to the Dismal Swamp. I started early in the morning, setting up on a picnic table in the park between the Canal and the walkway, along the canal. Even though it was midmorning, the weather became interesting, at  90° F and 90% humidity.

For this activation, I used the old IC 706 MKIIG and a modified Wolf River coil set up. I used the Chameleon 17 foot telescopic whip. This whip is Mil-Spec and has a great feel and quality of workmanship. However it is 11 inches too short for the Wolf River “Sporty 40” coil. To address this, I made an 11 inch jumper from solid copper wire left over from my Dad’s days with Southern Bell telephone, and fitted it on an alligator clip, clipped to the top of the whip. The other modification was not to use the three 31 foot radials. For this activation, I tried the KB9VBR “Magic Carpet” ground plane.

This is a 32 x 84 piece of aluminum window screen, laid on the ground, under the antenna tripod. It may be a dB  or so less than the radials, but it sure takes up a lot less space, especially in a crowded parking lot. The key is the Whiterook MK-49 made by ElectronicsUSA. It is my favorite backpacking key, lightweight and withstands being thrown into a backpack with no protection. This set-up worked well both on 20 and 40 CW, juggling CW keying with eating leftovers for breakfast until the rain came.

I then decided to wander on some back roads in Eastern North Carolina and wound up in historic Edenton, originally built in the early 1700s and the first capital of the Colony of North Carolina. Their diverse history is reflected in the town square, where there is a 13 Colony US flag, a monument to the Confederate War dead, and the British Union Jack!

The radio setup was very pleasant at the Historic Site (K-6842) near the Albemarle Sound, which begins at the Eastern North Carolina coast, and runs to the leeward side of the North Carolina Outer Banks on the Atlantic Ocean.

I decided to try the TR-45 Lite again, but this time with a Buddipole on 20 meter CW. Propagation was variable with early contacts in Utah and Idaho, but the band became difficult. It was very pleasant operating with the ocean breeze and looking at the 1886 Roanoke River lighthouse,  until the rain started again.

So it was time to pack up, but a return trip to spend a weekend in Edenton would be a very pleasant activity. On the way out of town, I passed a puzzling POTA  site, the National Fish Hatchery (K-8007), established in 1898, and home of an Annual Fishing Rodeo. Activating there was tempting, but the rain was prohibitive.

All in all, it was a very pleasant activation for the first NC POTA weekend. I got to test different radio and antenna configurations. I would say for the TR -45 Lite, the inverted-V worked best. For the ICOM IC-706 , the “Magic Carpet” aluminum screen worked very well and was very easy to set up.

I did not have time to do a head to head comparison of the antennas; that is a Fall project.  Please note I originally got a stainless steel screen from Amazon, but testing with the Rig Expert showed that it really did not conduct as well as aluminum and had higher SWR, so make sure to purchase the aluminum screen.

For a first NC POTA Weekend, the results were modest and certainly can be improved upon next year. Down east on the Outer Banks, Jockey’s Ridge and the Wright Brother Memorial  is on my future list, but an annual pilgrimage to the Dismal Swamp (especially in non-summer months) is a must.

Antennas, Field Reports, News, Portable, POTA, QRP, Videos

POTA with a 20 Meter Vertical Delta Loop and the Elecraft KX2!

15 Comments

There’s a portable wire antenna design I’ve been wanting to put on the air for POTA and SOTA for what seems like ages: a 20 meter vertical loop.

I mentioned in a Ham Radio Workbench podcast episode a few months ago that I planned to build a field-portable delta loop antenna and that led to a mini discussion about configurations, feed points, height off the ground, etc. and how all of those factors can influence the characteristics and dynamics of the antenna.

Vertical loops are pretty fascinating and incredibly effective.

Delta loops are super easy to build (no more difficult than an EFHW) but this summer has been insanely busy for me and I simply hadn’t gotten around to it yet.

Then my good friend Joshua (N5FY) who runs tufteln.com sent me a prototype 20M delta loop in the mail. We’d been talking delta loops and he couldn’t help but build one. He asked that I take it to the field and put it on the air, then give him any feedback and notes I might have.

Joshua’s design incorporates a 4:1 transformer and was cut to be resonant on 20 meters. I’d actually planned to build one identical to this because the type of loops I’ve deployed at home have been fed with ladder/window line which isn’t as portable as something I could feed with RG-316.

Holmes Educational State Forest (K-4856)

On Friday, September 1, 2023, I grabbed the delta loop antenna and the KX2, then made my way to Holmes Educational State Forest.

I knew that Holmes wouldn’t be busy and that there were a number of options for spots to set up.

After a little scouting, I found a great site to set up the antenna.

I planned to set up this antenna as close as I could to an equilateral triangle with the apex up about 30 feet and the feedpoint in the middle of the base of the delta.

Deploying the antenna in this configuration meant that I only needed one line in a tree to hoist the apex of the delta and two lines to pull out the corners of the base.

I brought along some paracord with tent stakes to secure the base corners of the loop. In the end, though, I simply attached the paracord to trees instead of using the stakes.

I (somewhat reluctantly) made a video of the entire activation including the antenna deployment. I wanted to take my time deploying this antenna for the first time, so the antenna deployment section of the video is much longer than usual.

You absolutely cannot see the loop in this photo, but it’s there…I promise!

In the end though? It wasn’t as difficult as I thought it would be. The last vertical delta loop I deployed was a 40 meter loop which is roughly double the size–in my head I was expecting the aperture to be larger than it was.

My arborist line and 12 oz weight hanging to provide a gentle tension to hold the apex of the loop up.

The 20 meter loop is actually pretty compact and almost as easy as setting up as an inverted vee.

With my loop properly deployed, it was time to hit the air! Continue reading POTA with a 20 Meter Vertical Delta Loop and the Elecraft KX2! →