Tag Archives: Antennas

Articles, Field Reports, Guest Posts, Portable Power, POTA, Solar

Pushing My 2016 Subaru Forester to its Off-Road Limits to Activate Buse Hill in CA-3287

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It’s another beautiful cloudless day in southern British Columbia (16 Sept, 2024).  My goal for today is to activate Buse Hill Lookout, located in Buse Lake Protected Area CA-3287, before the weather turns too cold and wet to venture into the area.

Buse Hill is about a 2.5-hour drive NW from Kelowna, BC where I live.  The last ¾ hour of the drive is on gravel range roads.  My wife Alexis (VE7LXE) is accompanying me on this trip, as always.

While planning for the activation, I closely studied Google Maps Satellite view, as well as Garmin GPS Birds Eye views of the activation area.  This helps me evaluate the terrain and access routes.  I also study the Gov’t of BC Mineral Titles online maps which give both satellite views and topographic views (before POTA, gold panning was my summer hobby and the BC Mineral Titles online maps were essential for knowing where to legally pan).

Access to Buse Hill Lookout, CA-3287. Ecological Reserve south-end access route. Tip: Click on images to enlarge view.

From these maps I can see that the last 1.5 Km is an undefined off-road access route.  From the satellite views, it’s very difficult to assess the viability of a route that my Forester can handle.  So, I knew there was a 50-50 chance I may be able to drive all the way up that last 1.5 Km.  With this in mind, we came prepared for two eventualities:  4-wheel it up, or backpack it up if necessary.

That means having two prepared POTA back packs; one with the KX3 for near car activations, and my KX2 backpack for hiking situations.

Continue reading Pushing My 2016 Subaru Forester to its Off-Road Limits to Activate Buse Hill in CA-3287 →

Antennas, Field Reports, POTA

Activating CA-4252 With A Novel Coaxial Sleeve Telescopic Vertical Dipole

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In recent times I’ve been feeling the urge to start experimenting with telescopic vertical whip antennas.  Vertical whip antennas appear to be somewhat simpler to setup than elevated dipoles.  So, it seems like a worthwhile endeavor to experiment with.

Recently, I purchased two Chameleons telescoping verticals whips:  their 17’ version and the 25’ version, for experimental purposes.  I’m looking forward to trying various configurations, which will likely not be until next spring or summer as our weather here in the Okanagan Valley of BC is starting to show hints that winter is just around the corner.  So, for now I have one specific configuration idea in mind that I have been itching to try:  a 1/2 λ Coaxial Sleeve Telescopic Vertical Dipole.  However, this configuration is required to be elevated with a tall mast.

In a sense, I suppose one could call this a Hybrid Telescopic Vertical Antenna because the top-half of the antenna will be a standard 17’ telescopic vertical whip from Chameleon.  And, instead of typical radials, the bottom-half of the antenna will be using the same concept of a Coaxial Sleeve Vertical Dipole, tuned for the 20m band.

I won’t take up too much space in this report outlining the construction details.  I just wanted to see if this antenna concept has any viable potential for ongoing uses.  This is the antenna I will be using today atop my 30’ carbon fiber telescopic mast.

Here we go with the events of the day.

Today I will be attempting to activate Vance Creek Ecological Reserve, CA-4252.  The Vance Creek activation spot is located about 1.5 hours drive NE of Kelowna, BC, Canada.  The access road into Vance Creek is a gravel forestry service road (FSR), just north of Lumby, BC.  I will be the 2nd person to ever activate this park, and the 1st to do it with CW.

We left home early with plans to make this another full day of playing with POTA.

Having never been here before, we drove the length of the reserve in search of a good spot and settled for a location just inside of the far-end of the park boundary at around 16:00 UTC (09:00 PDT).  We chose this location because it is one of the few areas to easily park off the roadway.  Beyond the sign titled “Woodlot” is a forestry logging harvest area (outside the park boundary).

Continue reading Activating CA-4252 With A Novel Coaxial Sleeve Telescopic Vertical Dipole →

Antennas, Field Reports, Guest Posts, POTA

Uncharted Trek into Trout Creek Ecological Reserve, CA-4221

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My goal for this summer is to do more backpacked day-trip POTA activations while I’m still physically able to. This is my 4th backpacked-in activation this past week or so. And a thank you to Thomas K4SWL for letting me share my adventures from the Canadian out-back.

Today’s goal is to activate Trout Creek Ecological Reserve, CA-4221 which is about one-hour drive south of Kelowna, BC, Canada, which is where my wife Alexis (VE7LXE) and I (VE7EFF) have lived for the past 12 years. Alexis accompanies me on all my POTA activations.

It is a beautiful late August day. The temperature is expected to be about 31℃, or 88℉.  The one-hour drive is just the beginning of the day’s adventure. We were able to conveniently park at the Summerland Golf and Country Club, but this is where all conveniences end for us.

Trout Creek Ecological Reserve has never been activated before – I’ll be the first. It’s no surprise this reserve hasn’t been activated before. It’s all wilderness with no trails to follow. I have to rely on my Garmin 66sr GPS and Pixel8 smart phone with Google Maps with Satellite View to help me navigate to and through the reserve in search for an optimal operating location.

I expected the trek to only be about 1 Km in with about 600 ft elevation gain. It’s all uphill, all the way. From the golf course parking lot, the hike starts out relatively easy. At first, there appears to be some semblance of a trail.

Continue reading Uncharted Trek into Trout Creek Ecological Reserve, CA-4221 →

Antennas, Field Reports, Guest Posts, Morse Code

Experimental Antenna Reins-in Surprising Results

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Editor note – Please enjoy this guest post from Jeff Bourgeois VE7EFF.

Today, September 6, I hope to POTA activate Inonoaklin Provincial Park CA-3626 in Southern BC, Canada, located on the shores of the Lower Arrow Lakes. On this activation, I will be using my novel experimental homebrewed Coaxial-Sleeve Dipole. The results were surprising!

We have been wanting to come back to this park since a brief visit to the area last summer.  I especially wanted to come back because, at that time, it had never been activated by anyone. I had plans to activate another park in the area that day.  Unfortunately, I was beaten to the draw just a few weeks ago by another ham.

The other reason I didn’t get here sooner was because it is a 3-hour drive east from our home in Kelowna, BC. 3-hours is pushing the limits of how far I’m willing to drive on daytrips, especially in mountainous areas. We rarely, if ever, do overnight trips.

We left the house very early in the morning on Sept. 6, 2024.  While the countryside is very beautiful enroute to the Arrow Lakes, I kind of dread the drive as the roads are often narrow, twisty-windy and up and down steep mountain passes.  At times it felt like being on a roller coaster.

Continue reading Experimental Antenna Reins-in Surprising Results →

Accessories, Antennas, Articles, How To, News, Portable, QRP

Construction Notes: VO1DR Monopod Antenna Mount

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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

Antennas, Field Day, Guest Posts, Morse Code, POTA, QRP

Experimenting during Field Day 2024

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by Vince (VE6LK)

Field Day 2024 started out with the best of plans to be spent with the best of friends and ended up totally different – and, unexpectedly, I had a hoot! With my carefully made plan behind me, my new last-minute plan was to run solo for Field Day in the backcountry of Kananaskis Country and bring along my new-to-me Nikon D3400 and lenses and rekindle my interest in (D)SLR photography at the same time as doing some experimentation with radio gear.

I grew up in a home with a scratch-built enlarger and a darkroom, so a love of taking pictures has been with me for a long time. My Father taught me patience to get the shot as he would set up a 120 format bellows camera on an air-triggered remote release to get closeups of chipmunks while we were camping, a process that took hours and yielded excellent results. My Brother, AG7GM, has attempted to instill within me the basics of composition, rule of threes and such and his wonderful skill in editing both stills and live video. While I have plenty of patience, with composition I think I’m fair to middling at best.

Thus photography has always been on my mind.

With a recent sale of a few ham radio related items, I had fun money, so just for fun I started looking [on Thursday before I activated] at used DSLRs and was shocked at how much camera I can get for such a relatively low cost compared to new. I had said once, 25 years ago when I divested out my 35mm kit, that when I could get a DSLR with a 25 to 300mm lens for <$500 I’d jump in… and finally that day is here, even if it means carrying two lenses. Of course, I started looking on the day before Field Day for deals – and scored them too! 🙂 Around these parts, good quality pre-owned consumer grade DSLRs are easily available. I purchased this as much for still photography as for ability in shooting high-quality video for my YouTube channel.

These peaks form part of the border between Alberta and British Columbia to the west

For me, Field Day has always been about the experimentation rather than chasing points. Trying new things. Changing up from the normal way I operate in the field. Comparing, analyzing and making notes as I go.

For example, and as a tribute to Chip Margelli K7JA (SK) after corresponding with his brother David, last year I attempted to wet a piece of string and see if the KX3’s tuner would match it and radiate a signal. Chip was known for many things, among them his proficiency in CW as he demonstrated on The Tonight Show with Jay Leno in 2005. David told me that he and Chip would do crazy and fun experiments like loading up clotheslines and wet string to experiment .. and it fostered a new direction I could take each FD and on some days between. The string experiment was a failure last year but I haven’t given up yet!

This year, I wanted to work with a few different antennas and a Charmast 100W battery pack from Amazon along with a USB-C PD 12v power cable for my KX3 [note: Amazon affiliate links!].

I wanted to know, in no uncertain terms, that the Charmast would or wouldn’t be as quiet as my trusty Talentcell LiFePO4 pack. The Charmast is also used in my field soldering kit with a Pinecil as it delivers USB-C PD. What better way to test this out than to head as far away from noise sources as possible, see the Canadian Rockies in their early summer glory with snow on the peaks, rivers running high (and cold) and the sun in the sky? Just for grins I would ensure that I was in POTA entities while doing Field Day.

Continue reading Experimenting during Field Day 2024 →

Accessories, Antennas, Comparisons, New Products, News, Portable, POTA, QRP, SOTA

Mike compares the new Explorer POTA20 with the venerable SOTAbeams Carbon 6 Mast

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Last week, I ran into my good friend Mike (KE8PTX) at Hamvention, and he was bursting with excitement over a new product he’d just purchased: the Explorer POTA20 Carbon Fiber Mast at GigaParts.

Mike is a massive fan of the SOTAbeams Carbon 6 telescoping pole and has been through two of them over the years he’s been doing field radio work. He told me that the new Explorer POTA20 is even better than the Carbon 6.

I don’t think Mike knows it yet, but after his recommendation, I ordered an Explorer mast—it’s backordered, so it’ll be a month or two before it ships.

Mike took this photo of his mast from a POTA activation this morning. You can see the mast left of the dead tree.

Mike is also a brilliant designer and has made a 3D-printed tent stake holder that fits on the end of both of these poles. He told me that these 20′ carbon fiber masts are so lightweight that there’s no need for guying the pole, even in fairly windy conditions. His simple tent spike is all that’s needed to hold a carbon fiber mast in place.

Videos

In the following video, Mike compares the Carbon 6 with the new Explorer mast and speaks to the utility of using a tent spike to secure the mast:

Thank you, Mike, for sharing this video and the tip about the new Explorer mast!

Again, it’s currently backordered at the time of posting, but you can place an order at GigaParts. The price is $79.95 plus shipping.

Accessories, Field Radio Kits, Guest Posts, Morse Code, News, Portable, POTA, QRP, Travel

Planning a POTA Babe Trip – Part 2

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(Note: I cut my Florida POTA trip short as I needed to take care of some personal business. I apologize for the change of plans and the inability to communicate that to y’all. I appreciate everyone’s support of the trip and the QSOs of those who hunted me. Articles will be forthcoming for those activations in the near future.)

Those of you who have followed my journey on QRPer know that I wrote an article about my kit for the trip I took last summer to Nova Scotia. Since then, what ham radio equipment I take with me has changed, partially because I am not flying to a different country far from home and partially because of my experiences with what I generally do and don’t need. I thought I’d share what my kit currently looks like for the spring-break Florida trip.

Here is a photo of what ham radio-related gear I am taking on my Florida POTA trip. We’ll first look at what I have in each section of the Elecraft bag I take with me and then a few items that do not fit in this bag but are still along for the ride.

When I purchased my KX2, I also purchased the Elecraft bag. Though the bag is bulky in its profile, it was a worthy purchase due to the amount of stuff it can store in one place in a well-organized manner.

The bag has three compartments.

In the first compartment is my main man, Craig, my KX2. He is the rig I use for all my QRP adventures out and about. I do have a protective cover I purchased for him but haven’t installed yet. I have a fear of messing with electronics and, though installing the shield isn’t rocket science, the project seems overwhelming enough that I haven’t tackled it yet.

Also in this first compartment are my throw bag containing an arbor line and throw weight, some S-carabiners, my homemade radials for the AX1, the tripod mount for the AX1, and a pencil and earbuds. I find I copy CW much better when I have a headset of some sort.

In this compartment, I used to have a back-up key. However, in its place is a new single-lever paddle from CW Morse [QRPer affiliate link]. I am using this key because it is wired to be a cootie or a paddle via an internal switch. I discovered my KX2 doesn’t balk at using this key like a cootie unlike when I use the CW Morse SP4. I desire to use QRP for more than POTA, specifically for SKCC and calling CQ for ragchews. SKCC requires a mechanical key and, as the cootie is my favorite key, this new key should fill the need  I discovered the last time I visited Skidaway Island.

In the second compartment, I have the AX1 and the Tufteln EFRW antenna. Those of you who have read my articles know I generally deploy the Tufteln EFRW antenna. On this April Florida trip, I plan to use the AX1 and the Chelegance MC-750 more often in preparation for my summer POTA trip. I anticipate I’ll be limited by terrain and park rules from deploying an antenna in a tree so more experience with verticals will be helpful.

In the third and final compartment are some odds and ends: neon pink flagging tape, an allen wrench for adjusting my CW morse keys, some twine, a short length of wire with an alligator clip on the end, two shock bungee cords, the cord for my CW Morse single-lever key, and a splitter for the headphone jack. I’ve used all these items (except the cord for the new key) at one time or another so I don’t want to leave the house without them.

Here are items I am also taking that don’t fit in the Elecraft bag.

The Tufteln kneeboard, POTA flag, and a notebook. I really like using pencil and paper for my POTA logs. I hold my key in the left hand and send with the right. For some reason, juggling that with paper is more manageable to me than logging in my phone or a laptop. The one thing I miss out on by doing that, though, is not knowing people’s names except those I’ve encountered many times. (And even then I forget names in the busyness of an activation so if I do, please forgive me.) I like to thank people by name at the end of the QSO rather than just their call sign if I know their name. I learned to do this in SKCC exchanges and I think it is a respectful and genteel practice. The one advantage I see to using a logging program is that I could do that with every QSO.

In a Tom Bihn bag, I have my RG-316 coax in three lengths (10’, 20’, and 50’), a short bungee cord, a stereo connector, and a newer version of the SP4 (aka The Minion).

Also coming along for the ride is the Chelegance MC-750. [QRPer affiliate link]

The last pieces of equipment I am bringing are for the first park I will visit – Lafayette Wildlife Management Area. In areas that allow hunting, Daisy and I wear blaze orange, even in the off season. Though as hams we try to be law abiding, we need to remember there are others out there who are not. When it comes to areas in which hunting is allowed, it is wise to wear blaze orange year-round because hunting violations due happen.

There you have it – the POTA Babe’s current QRP kit. I have one last question to address in this series – how I plan my trips. To find out, stay tuned…

Antennas, Guest Posts, News, Portable, QRP, Videos

Scott’s Self-Supporting Random Wire Antenna System

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Many thanks to Scott (KK4Z) who shares the following post from his blog KK4Z.com:

K4SWL+ Antenna

by Scott (KK4Z)

On a recent post on QRPER.com, Teri KO4WFP was at a park in Florida that did not allow wires (or anything else) in their trees. Many POTA activators use End Fed Half Wave antennas which usually require one end in a tree. While it doesn’t happen at all parks, not being able to hoist your antenna could bust an activation.

I realized this may happen to me even though Georgia appears to be pretty lenient when it comes to such matters, I decided to switch to a park friendly antenna. I have been a fan of QRPER.com for quite some time and occasionally Thomas will repost something from my humble blog. That being said, it was K4SWL that got me started using a random wire antenna. My basis for my antenna was his speaker wire antenna which was a 28.5’ vertical antenna with a 17’ counterpoise. I used it a few times in that configuration and then started to modify it. I call this antenna my K4SWL+.

Some of the differences are I use a push-up pole to get the antenna in the air and at the base I use a 9:1 UnUn and a 1:1 Choke to keep RF out of the radio. A random wire antenna can feed RF back into the coax.

The wire is 14 ga. coated flex weave from The Wireman. This was left over wire from some other antenna projects. When I started this project I was using 22-24 ga. coated wire from SOTABeams but realizing there was no need to save weight, used the heavier wire. This allows me to dual purpose the antenna both for FunComm and EmComm. The insulator at the top is 3D printed with my call-sign and the base is U-type lugs. I find these are the best as I do not have to take the nut off of the antenna studs and if pulled hard will come loose instead of damaging the UnUn. I connect the antenna to the top of the push-up pole with a small Nite-eze “S-biner” size 1.

The 9:1 UnUn comes from Palomar Engineering. I have already created a blog post about how to build it and it can be found here: https://kk4z.com/2022/05/28/91-unun-qro/

Part of this blog post was to bring the different components together into one blog post.

The 1:1 Choke can be found here: https://kk4z.com/2022/08/15/lightweight-choke-balun/

I made two different types but I found the second works much better.

The project is pretty easy, the only caveat is to pay attention to what wire goes where. Putting it all together, you need a push-up pole, a Flag holder and maybe a trailer hitch extender. I will provide links below. The Flag Pole holder I used was not available so the link I used is a probable substitute. I have a trailer hitch on both my truck and my camper, When I pull into a campsite I have a choice of which hitch to use to keep my antenna clear from the trees. With the antenna up, I wrap the antenna wire around the push-up pole from tip to base, to prevent the wire from sagging near the tip. I attach the UnUn and choke to the mast with Stretch Velcro Straps. With my antenna up I have park employees drive by me all day along. Most of the time we exchange a friendly wave and occasionally one will stop by for a chat. I have had zero issues with this antenna at any of the parks I have visited.

How does it play? It has pretty much been a main antenna for just about all of my POTA activations. You can go back through my blog post and see what equipment I used with the antenna and the accompanying QSOMap. You do need an antenna tuner with this antenna and I typically use an LDG Z-11 Pro which I’ve had for 15+ years. The antenna tunes up from 80 to 6 meters and I have run the power as high as 65 watts. I normally run 10-35 watts depending on band conditions. I have tried it on 160 meters and while I can get a match, I don’t think much RF is leaving the antenna. I’ve made a few contact with it on 160. If you like to work 160 meters during a POTA activation, I suggest a Chameleon EmComm II with a 60’ antenna and a 50’ counterpoise. I run it as an inverted L with the apex about 20’ up my push-up pole and the end sloping down to something not a tree. Last time I tied it to the lantern stand at the campsite. It worked pretty well and I was able to make contacts on 160.

Video:

Click here to view on YouTube.

If you’re looking for an antenna that you can set up almost anywhere, with little or no hassles, take a look at this one. Don’t forget to check out the short video above. 73 — Scott

Antennas, Field Reports, New Products, News, Portable, POTA, QRP, SSB, Videos

SSB and CW QRP POTA: Testing my new KM4CFT End-Fed Antenna Kit!

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A few weeks ago, I mentioned that Jonathan (KM4CFT) sent me one of his new QRP end-fed half-wave/random wire antenna kits.

When my friend, Alan (W2AEW), caught wind that I planned to buy some 26AWG wire for this build, he sent me a spool of wire from a large reel he’d recently picked up at a hamfest.

What a nice guy! The blue wire is absolutely ideal for portable antennas.

Being the nice guy he is, Alan actually published a video about building Jonathan’s antenna kit on his YouTube channel. I highly recommend watching it!

Before I received the kit, I already knew what type of antenna I’d build: a 30 meter end-fed half-wave (EFHW) linked with a 40 meter extension. This antenna design has been on my mind for some time and Jonathan’s kit was the perfect excuse to build one.

Why a 30M EFHW with a 40M extension? Because a 40M EFHW gives me excellent SWR matches on 40, 20, 15, and 10 meters without needing an ATU.  A 30M EFHW gives me matches 30 and 17 meters.

Thus, with one linked wire antenna, I can cover 40, 30, 20, 17, 15, and 10 meters! That’s a lot of bands!

And since the antenna needs no extra matching, it’ll work with my transceivers that lack an internal ATU.

The Mountain Topper MTR-5B I acquired earlier this year.

In fact, I originally thought about this antenna design to use with my Mountain Topper MTR-5B which covers 40, 30, 20, 17, and 15 meters.

I built this antenna by first trimming it for a 1:1 match on 30 meters including a loop and strain relief to attach the extension.

When I was satisfied with my 30M EFHW, I then made the 40M extension, attached it to the 30M section with 2mm bullet banana connectors, then trimmed the antenna for a 1:1 match on 40M.

I spent the better part of 60 minutes trimming this antenna. I feel like patience really pays off because it’ll set up the antenna for good matches on all of the upper harmonics. Admittedly, I was a bit pressed for time that day, so I only tested this antenna in one configuration (an inverted vee shape) so hadn’t checked the SWR as a sloper or vertical.

My advice is to aim for a 1.3:1 or better match on 30M and 40M–that should be very doable if you wound your transformer correctly.

This was my first attempt at making in-line links, so I wouldn’t consider link my method as a “best practice”–rather, check out K7ULM’s guidance for making in-line links. Continue reading SSB and CW QRP POTA: Testing my new KM4CFT End-Fed Antenna Kit! →