Tag Archives: Antennas

Antennas, Comparisons, Guest Posts, News, Portable, POTA, QRP, SOTA

How I found the best antenna for my SOTA/POTA activations

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How I found the best antenna for my SOTA/POTA activations

by Thomas (DM1TBE)

Intro

Until January this year I had a German “Klasse E” / CEPT-novice amateur radio license (equivalent to the US General Class), which limits the use of HF to the 10-,15-, 80- and 160-meter bands. When I started with SOTA I used homemade single band end-fed antennas most of the time. However, that is only feasible for the 10- and 15-meter bands.

Unfortunately, both bands are very moody and sometimes they have not worked at all. Unlike the UK for example, FM is uncommon for SOTA in my home association DM (i.e. Germany Low Mountains). You can be lucky and get your 4 QSOs, but I did not want to rely on pure luck.

Therefore, I bought an end-fed half-wave antenna for 10-, 15-, 20-, 40- and 80-meter bands, after some experiments with 10-80-meter end-fed half-wave antennas, from a small German company called ANjo.

Although I could not use the 20- and 40- meter bands at that time, the EFW80-10P (en: auto-translated) antenna gave me the possibility to use the 80-meter band. The antenna could also be tuned for 15. It has a mechanical length of 23.6 m / 77 ft and a coil for the 80-meter band. It is pretty lightweight with 0.4 kg / 14 oz and allows up to 30 watts PEP – more than enough for me. 80-meters is not the best band for daytime SOTA activations, but in 21 months doing SOTA activations, it worked 37 times and tipped the scales for an activation from time to time.

It was sometimes a bit tricky to raise the long wire into the air, but it always worked … better or worse …somehow … like here in the woods along a trail.

In January this year, I upgraded my license and a new world of HF-bands opened for me. Although I have learned a lot about propagation for the exam, I am in favour of a German saying: “The difference between theory and praxis is larger in the praxis than in the theory”. Continue reading How I found the best antenna for my SOTA/POTA activations →

Antennas, Articles, Guest Posts, News, Portable, POTA, SOTA

Skip recommends the QRPguys DS-1 portable antenna kit!

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Many thanks to Skip (K4EAK) who shares the following guest post:

The QRPguys DS-1 Portable Antenna Kit

by Skip (K4EAK)

There have been several videos and extended comments lately about the Elecraft AX1 and AX2 antennas, both of which function remarkably well for a small, highly compromised antenna.

For those interested in other, similar designs, especially those hams who find that building the equipment is half the fun, another option to consider is the QRPguys DS-1 antenna.

The DS-1 is similar in concept and design to the AX2. It consists of a base-loading coil, a 46.5-inch collapsible whip, and a plate to attach the antenna to a small tripod. One can also purchase an add-on 40-meter coil. The can be deployed in just a couple minutes and, when collapsed, the longest portion is only 6.5” long, easily fitting in the palm of one’s hand. QRPguys recommends a 16.5′ counterpoise; I use two such wires, usually spread out at a 180-degree angle. I’ve also used it with a clamp-on mount and a car window mount.

Building the antenna is simple and took me less than an hour. After installing a BNC connector into a brass plug and inserting the plug onto a length of PEX tubing, one simply runs the supplied 22AWG wire from inside the tubing, out and around making 22 turns, and then sealing it with a length of heat shrink tubing.

There are really only two aspects of assembly that are slightly more difficult. The first is that it’s necessary to drill and tap two holes for 4-40 screws, which obviously means that (1) one needs a 4-40 tap and (2) one needs to be careful tapping the threads to assure a clean cut. The second is that the heat shrink tubing, at least as supplied in my kit, was grossly oversized, which required some finesse in getting a final product that was at least reasonably aesthetic, to say nothing of accomplishing that without dry roasting my fingertips.

Field testing of the DS-1 shows that it works surprisingly well. The SWR is well below 2.0 across almost all of the 20-meter band and where it is higher than that (the upper end of the voice portion), the KX2 internal tuner can tune it easily. As one would expect, on 40 meters the antenna has a somewhat narrower range, although the KX2 tuner has handled it on all of the frequencies I’ve tested so far (all CW). And it appears to be efficient enough.

I have used it on numerous activations and consistently get to the requisite 10 contacts within 20 minutes or so after getting spotted. After that, the number of contacts depends on the time available, but for those occasions when I have only a 30-minute window for an activation, the antenna is a convenient and practical alternative.

I keep the antenna, the tabletop tripod, and the counterpoise wires in the water bottle pocket of my pack, ready for use whenever I have a few moments for a quick activation.

73 Skip K4EAK

Click here to check out the QRPguys DS-1 antenna

Antennas, Field Reports, Guest Posts, News, POTA

VE6LK: Antenna tuning on Superb Owl Sunday

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(This article is full of educational and fun links – click on as many as you wish)

Antenna tuning on Superb Owl Sunday

by Vince (VE6LK)

While many in North America were watching a number of Superb Owls move a pigskin around a playing field, I was off to play radio, successfully, for the first time in weeks. This is part of my goal to activate 200 CW POTA contacts per month this year.

During recent visit to Vancouver attempting to operate from within my hotel room, and utilizing the Edisonian Approach, I was shown -more than once- what did not work. This will no doubt be a discussion point on an upcoming Ham Radio Workbench Podcast. I was therefore in very bad need to get back on the air while operating portable. I was close to feeling twitchy and in need of some POTAXXIA (Hyperradio Moduzolium). A plan was needed!

My goals were to trim out a new-to-me EFHW (thanks VE6VID), and make some contacts while operating outdoors. The weather was forecast for 50F, but turned out to be unexpectedly windy. Also, when the wind comes off the Canadian Rockies in Southern Alberta, it cools the area where I’d be (downwind), so a choice of operating location was key. I love going to this park for the moment that you drive west along Highway 533 and come around the corner as you see here in this short video.

Chain Lakes Provincial Park (VE-1168) is located between the Porcupine Hills and the Rockies on Highway 22 (locally known as the Cowboy Trail) in Southern Alberta, about 90 minutes south of Calgary. It’s especially gorgeous at sunrise and sunsets. A campground, lake with boat launch and a day use area all adorn this park created for water management with an earthen dam. While it is in a valley, the wind can be howling on some days. On this day it would prove to be just above a nuisance, sort of like mosquitos in the spring -you can live with the nuisance, but only for so long before you blow a proverbial gasket.

Short video – beautiful site and babbling brook

I located a lovely spot below the dam -and the majority of the wind- however it was outside of cellular range. I’d need to rely on the Reverse Beacon Network to spot me. The RBN will, in turn, post your spot to the POTA website once it hears you if you schedule your activation in advance.

RBN showing spots on 30 to 10m
Overhead site view showing my two operating positions

The place I found would only be more perfect were it warmer than 45F and without wind. A babbling brook was by the picnic table, and a nearby footbridge had built-in supports for my painter’s pole that would serve as the far end support. I’m pretty sure that they weren’t intended for me specifically, but they were the perfect size to simply slide the pole into place and hold it firmly. By luck I parked the truck the correct distance away with it’s drive-on mount and 28′ Fibreglass Flagpole from Flagpoles-To-Go via Amazon. Continue reading VE6LK: Antenna tuning on Superb Owl Sunday →

Antennas, Guest Posts, News, Portable, Reviews

Guest Post: Reviewing the Chelegance MC-750 (Part 1)

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Many thanks to Charles (KW6G) who shares the following guest post:

Product Review: Chelegance MC-750 Portable Ground Plane Antenna, Part 1

by Charles Ahlgren, KW6G

I recently purchased a Chelegance MC-750 portable ground plane antenna from DX Engineering.  Essentially, the antenna system provides a ¼ wave portable vertical antenna with 4 counterpoise wires that operates on 20 through 10 meters.  The antenna will also operate on 40 meters with the provided loading coil.  The manual states the antenna will support 6 meter operation, but no instructions are provided on how to do so.  30 meter operation is not supported.   It appears from our initial testing that no ATU is required.

Here are some of my thoughts on the antenna.

Product Description

The MC-750 comes with the following components:

  • GROUND ROD / ANT BASE
  • 50 CM ANT ARM
  • 5.2 M WHIP
  • 7 MHZ COIL
  • 4  COUNTERPOISE WIRES (radials)
  • COUNTERPOISE WIRE COLLECTOR BOARD
  • CARRY BAG

As provided, it is designed to operate on  the 40, 20, 17, 15, 12, and 10 meter bands without any modifications.  Six meters is also supported per the manufacturers manual, but no guidance on how to do that is offered in that document.   However, finding the proper length of radiator for 6 meters should be straightforward using a tape measure to set the proper whip length.

[Update: Chelegance notes that to operate 6 meters, simply extend the last segment only of the whip (see photo) and for 30 meters extend the last four segments of the whip and 15cm on the 5th segment (see photo).]

I checked the ground rod / antenna base with a magnet and confirmed it is made from stainless steel as both components are not magnetic; a characteristic of stainless.   Both the ground rod/ antenna base and the 50 cm antenna arm (which was also non-magnetic) had a hefty feel (together, they weigh about 2 pounds), therefore I think it safe to assume that these components are made of stainless steel.  Since most ops will undoubtedly use the antenna arm as an aid to inserting / extracting the ground rod into / from the ground, it seems a prudent decision by the manufacturer to have this piece fabricated from a strong, stiff  material such as steel.  The machine work used to fabricate these parts appears to be quite good – the fit and feel were excellent, with no sharp or ragged edges to cause problems in the field.

I measured the whip while set at the various position marks for 20 through 10 meters.  The band markings on the whip were accurate – giving a 1/4 wavelength radiator when combined with the 50 CM ant arm length…On 40 meters, the whip and rod measured about 1/8 wavelength.  The required the loading coil needs to be inserted between the whip and the rod (at approximately 1/10 the total 40 meter whip height above the base).  If you want to operate this antenna on 30 meters, it appears that you need to provide an extra 1.4  meter of additional rod as a quarter wavelength ground plane at 10.1 MHz  requires a 7.1  meter radiator.  Six meter operation would require a whip of around 4.7 feet.  With the whip fully collapsed, the length of the rod and antenna arm measures 40-1/4”.  Therefore, if 6 meter operation is contemplated, extending the whip about 16 inches from fully collapsed should suffice.  However, I don’t think that an antenna configuration such as that would be a very good performer unless it were elevated from ground level; or maybe it would be good for a SOTA activation? Continue reading Guest Post: Reviewing the Chelegance MC-750 (Part 1) →

Antennas, Articles, How To, Mobile, News

Dave sorts out vehicle-mounted antenna SWR issues

9 Comments
Photo by Katie Musial.

Many thanks to Dave (K1SWL) who writes:

Comments on vehicle-mounted antennas

by Dave Benson (K1SWL)

As with Rand’s recent post about his effective vehicle setup, I and others also use a small operating table inside the vehicle.  I’ve tried a number of approaches to antennas.  Without elaborating on those schemes, I’ll note that winter is now closing in here in NH. As a result, I’m now operating exclusively from my truck. My interest is now in minimizing setup and tear-down times.  Barry (WD4MSM)

also commented about the improvement in vehicle-mounted antennas with an added ground.  I’d like to quantify that.

I’d recently ordered a number of Hustler Mobile antenna components. They’re used as a stationary-portable setup using that company’s high-quality mag-mount. As I first evaluated the antenna, I was disappointed to find the minimum SWRs to be on the high side.

These results were related to the ‘floating’ coax shield, which serves as a counterpoise with the mag-mount setup.  Worse yet, these results were inconsistent. Touching the coax connector shell at the antenna analyzer caused the SWR to jump up, as did just changing the way I held the analyzer. Bad juju! It means RF inside the vehicle, with the potential for RF-‘hot’ symptoms at the rig..  Adding a 1:1 balun inline eliminated the stray RF at the rig, but didn’t do much for the SWR. It’s also just one more gadget to bring along.

A better fix was a custom bracket that bolted to the truck frame. I first confirmed that there was low-resistance continuity between a target location and the vehicle’s cigarette lighter shell.  This was something of a ‘comedy of errors’. I had a sheet-metal angle bracket on hand and went to work enlarging a hole in it. This had the usual outcome: a drill bit grabbed the workpiece and spun it. The bracket itself was buckled beyond redemption and my finger’s now healing well.  A length of 1-1/2 inch aluminum angle bracket was just the ticket.   Note that the mounting hole needs to be offset from the coax fitting mount. This avoids an interference between the mounting bolt and coax connector shell. Ask me how I know.  The bracket assembly uses a specialty coax fitting from DX Engineering. It’s their part number DXE-UHF-FDFB.

This bracket is bolted down on one of the corners of the Tacoma’s passenger seat assemblies.  It’s the closest location to the antenna I found without drilling holes and cutting the coax.  For this vehicle, it’s a 10mm bolt and was paint-coated for appearance reasons. I replaced it with a stainless-steel bolt from a hardware store. It’s important to include a split-lockwasher between the bolt and the bracket. This’ll keep the conductivity to the frame good over time. The bracket is deburred and its corners rounded to preclude injury to passengers.

In any event, it’s out of the way of the seat’s legroom space. A 3-foot coax cable assembly brings the coax nicely up behind the rig atop the operating surface.

So- how’d it work? It’s like the difference between night and day!  The broad SWR curves vanished – replaced by typical characteristics for monoband antennas. The sensitivity to handling the coax has vanished.  (A representative curve at right.) The curves are narrower, and that’s actually a good sign- it means that unwanted resistances have been reduced. 

With this fix in place, here are the SWR minima:

Frequency    SWR

14060        1.04:1

21060        1.05:1

28060        1.16:1

I took advantage of the CQ Worldwide CW Contest this past weekend. I was able to work 101 stations on 10M, 15M and 20M with this setup.  That was from a State Park 5 minutes away.  The attraction was a large and sunny parking lot, and solar gain was such that I needed to leave the truck door open several times.  This area is kept plowed out in winter, and I may try for the POTA ‘kilo’ award from there at the 1000-contact benchmark.  

We’ll see….   73, K1SWL

Antennas, Hacks and Hints, How To, News

Mike turns a trailer wiring harness into ready-made ground radials

6 Comments

Many thanks to Mike (KE8PTX) who shares the following tip:

[Recently, I walked into a] big box store and this caught my eye:

When separated, they have very little memory.

So now we have four 25 foot radials. Bonus was all were different colors. Easy to untangle.

Performance, so far, is good. Total price with clip: 12 bucks.

That’s a brilliant tip, Mike! Thank you for sharing. Like you, I’m always on the look out for products that could serve double duty in the world of amateur radio. While one can find less expensive sources of wire, for 100% copper wire pre-cut to a standard radial lengths, this is a pretty good deal!

I did some searching and pricing varies between various suppliers. 

 

Sample Retailers:

Thanks for the tip!

Antennas, Field Reports, News, POTA, QRP, SSB

Guest Post: Breaking 100 QSOs during two QRP SSB Activations

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Breaking 100 QSOs during two QRP SSB Activations

by Joshua (KO4AWH)

Back in May I had to travel last minute for work to North Dakota. I typically bring radio gear in the event that I have some time to do a Parks On the Air activation. This trip presented the opportunity to activate a park in Minnesota as well as one in South Dakota. I didn’t have much time to plan these activations, but I knew I had an early enough arrival in the afternoon that I could likely activate a park in MN and then in SD. So, I picked out a park in MN close to my destination. I could go activate in MN then get over to a park in SD and activate there.

I found a nice looking State Park in MN. The idea was to activate as quickly as I could and then get back to a park in ND with enough time to activate before it got too late. K-2482 Fort Snelling State Park had 110 successful activations. That is always promising when planning out an activation. I got my rental car and headed to the park.

I also had recently purchased a HFJ-350m which is a base-loaded coil with an extendable whip. I found a tripod base I could print online and then designed an adapter so I could install a SO-239 and RG316 lead with a BNC connector. I had just tested this setup in the back yard and knew it worked, although I certainly knew it was a compromised antenna.

HFJ-350m setup on custom tripod in the backyard for testing
Custom 3D Printed Tripod with BNC Connector

I typically bring my Raspberry PI4 loaded with Build-A-Pi and then run digital modes from my phone or Tablet. My plan was to activate this park with the compromised antenna running 5W on FT8 at the first park and then go to my second park and run a full half wave wire in a tree on SSB at 10W.

Not much to say about the activation in MN. The state park was nice but where I set up presented quite a bit of RF noise. Not so much of a problem since I was running digital. After a bit of adjustment on the whip I was tuned for 20m and started hunting a few FT8 stations. I did make a few QSOs while hunting but I then started calling CQ and had a bit more luck. I think because my signal was quite weak, calling CQ was a bit more efficient as only those who could hear me were calling back. While hunting, if those calling CQ were running a bit more power, I was unlikely to get in while running lower power and on a compromised antenna. I got the activation completed with 12 QSOs and packed it up and headed to the next park.

Continue reading Guest Post: Breaking 100 QSOs during two QRP SSB Activations →

Antennas, Guest Posts, Homebrew, How To, News, Portable, QRP

Sam builds a tiny tabletop HF antenna

18 Comments

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

Antennas, News, Portable

Honing my mag loop tuning skills

22 Comments

Yesterday, I posted the photo above on Twitter.

I couldn’t help it: I’m not an “Instagram Moment” kind of guy, but the fall leaf colors this year have simply been stellar. Any excuse.

Where was I? Oh yes…

Truth is, I was in the front yard practicing my loop tuning skills by hunting parks across 30, 20, and 17 meters.

The loop is the excellent Chameleon F-Loop 2.0 (which has since been replaced by Chameleon with the 3.0 version).

I’ve used this loop a few times in the field and even once from inside a large brick community building while doing an FT8 demo.

Loops are a brilliant solution when you have:

  • QRM from local noise sources,
  • limited space to deploy an antenna,
  •  or need a very low-impact and small footprint antenna (very handy for those historic and archeological POTA sites).

The trade-off, of course, is that they have a high “Q”–meaning very, very narrow bandwidth. Basically, anytime you move frequency? Yeah, it’s time to re-tune.

The environment around a loop can also have a pretty significant impact on your ability to tune it as well. For example, metal support structure in a building, window frames, metal poles, vehicles–anything like this nearby can have an impact on your ability to tune a loop and obtain a low SWR.

It’s for this reason I use them so little in the field–where I live, wire antennas are so easy to deploy and use.

But sometimes loops are the perfect tool, so knowing how to efficiently and effectively use them is important.

The F-Loop packed

I thought I had posted an activation video using the F-Loop, but looking back I realize I have not.

Yesterday, I decided to pack the F-Loop in my larger Spec-Ops Brand T.H.E. Pack which can easily hold the entire loop, folding tripod, and antenna analyzer.

I always fully set up an antenna before packing it in a new pack just to make sure I’ve included all components.  I used this as an excuse to improve my loop tuning skills by intentionally chasing POTA stations across the HF bands. I worked all of the stations I hunted (five, if memory serves).

Twice I obtained a brilliant match just by using my ear (listening for the HF band noise level to increase as I tuned the variable cap) and the rest of the time I turned to my RigExpert handheld analyzer to find a low SWR.

I’m looking forward to taking the F-Loop to the field soon just to see how well it performs. After my practice today, I do believe I’ll keep the antenna analyzer packed with the loop–it makes it so easy to find a good match.

I find the F-Loop a wee bit easier to tune than my W4OP loop. The W4OP loop is also a brilliant loop if you can find one–I recently gifted mine to a friend. Here’s my review from a few years ago.

I’ve used an AlexLoop once and was impressed as well. That’s another antenna I may review at some point.

Commercially-produced mag loops are pretty expensive though. I do plan to build a 20M mag loop antenna before end of year.  They’re surprisingly easy to build if you have a good variable cap.

Curious how many of you regularly use mag loop antennas. If you do, what make and model? Or is your loop homebrewed? Please comment!

Antennas, Articles, Guest Posts, How To, News

Steve’s Homebrew Vertical Antenna for POTA

15 Comments

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 →