Tag Archives: ft8

The Resonance

The reason why I would bother with this topic is twofold: One: I think better antenna systems are actually better; and Two: Technical concepts are central to amateur radio and should be understood and employed as often as possible. I’m discussing these antenna concepts in simple terms in the interest of keeping it accessible. Hopefully it leads to some further investigation and a different way to think about antenna systems.

WHAT IS RESONANT?

In the Venn Diagram world it can be said: Not all 50 Ohm feedpoints are resonant, and not all resonant radiators present 50 Ohm feedpoints. I have seen much confusion between “resonance” and “impedance match” on internet forums/platforms/videos. This what drove me to churn out this post.

Resonance in an RF radiator actually does make a difference. I’m a fan of Hemholtz and resonance is a real thing. When I assess a antenna design I start at the radiating element or elements. If that element is not a known and desirable harmonic relation to the fundamental frequency of interest I consider it a non-resonant design. If there is a matching unit connected to a non-resonant radiator I consider it a tuned circuit. When the goal is efficient and predictable RF radiation you have resonant radiators, and then everything else.

Recently there has been an explosion in the use of end-fed wire antennas. I use a few of them and they are an easy way to get on the air, usually on multiple bands. I have made plenty of contacts on these antennas, but at no point was I under an illusion that I was using an efficient antenna system. The now ubiquitous End Fed Half Wave is a strange bird, It utilizes a half wave radiator with a feedpoint impedance of about 3000 ohms, and is operated without a traditional ground plane or counterpoise. The high impedance feedpoint is matched to somewhere near 50 ohms with a 49:1 or similar toroidal un-un transformer. That is not a recipe for efficiency. The power ratings on the matching transformers tell you all you need to know: These matching units get hot, and that heat is your RF not making it out into the world.

PAR Trail Friendly on a Spiderpole

That’s not to say it’s a bad design. It solves a few of the issues that keep many hams from being able to get on HF. You can hang it from a single support, as opposed to needing two or three for a horizontal dipole. It’s also easy to erect on demand, which is great for hams who want to operate portable stations or if they have a compromised (small, HOA, etc…) QTH. I use a 12m Spiderpole and a PAR Trail Friendly when Inwant to get on the air quickly. Also, thanks to the magic of harmonic resonance, it is common to find a match on more than just the fundamental frequency.

Another common design is the random length end fed, usually known by the 9:1 un-un transformer used to feed the non-resonant radiator. The trick here is to find a radiator length that is not resonant on any band you want to work. The hope, and I do mean hope, is that the feedpoint impedance will be somewhere in the 200-800 ohm range, where it can be matched to 50 ohms using a second matching device. Again it has the advantages of ease of setup and multiband capability. The tradeoff is even steeper than the HWEF. This design is force-feeding a non-resonant radiator, has an even lossier (IMO) un-un, and requires a second matching device to get all the way to 50-ohms.

A problem both designs share is the difficulty in modeling a radiation pattern. Even with many analyses and many users over many years nobody seems to be able to say much beyond “omnidirectional”. That’s not too helpful. The main issue in modeling these systems is properly representing the ground/counterpoise. Most installations (mine included) require a common mode choke (CMC) near the radio end of the coax to keep RF from energizing the radio’s earth ground. How efficient does that sound? Do we have any idea what these antennas are actually doing wit the RF that makes it out into the world? Empirically I think we do. Scientifically, predictably, I don’t think we have a good handle on it.

So, how important is the efficiency of a transmitting antenna?

Hams with even some basic experience on HF know that you can make contacts on almost anything. Take a simple transmatch design like the MFJ-901, hook it to a rain gutter, and make a contact. Do we know anything about the radiation pattern, efficiency, or bandwidth? No. We are just interested in forcing something conductive to radiate RF, and hope for the best. The magic of radio waves takes care of the rest. If enough of your RF makes it out in the correct direction you will make a contact. Your signal might even be strong! But this is where it helps to be aware of confirmation bias. The science of radio communications involves being able to control where your signal is going, and control the system design to connect you with the intended destination. Having made some contacts is almost inevitable. Making the contacts you want to make when you want to make them is where the game gets interesting.

In the food-chain of antenna designs these lossy designs are somewhere in the “krill zone”. A good efficient design, properly installed is somewhere in the “cordata zone”, and a very efficient directional design mounted high and in the clear with directional control is “blue whale” territory. At some point the operator is limited by their Effective Radiated Power (ERP) and the weakening of the transmitted signal with the square of the distance from the antenna. Using 10-30% of your RF to warm a toroid is cutting in to your effective range. Every system has limitations, but when running 10, 30, 50 watts at the finals, I feel that making the most of it is important. Every improvement in efficiency and pattern control brings you up another link in the radio food chain.

Mitigating Factors:

Certainly the parallel popularity of end-fed wires and weak-signal digital modes, best represented by FT8, are not coincidental. FT8 allows working at lower signal to noise ratios which is like getting that lost RF back when compared to working SSB or RTTY. More efficient antennas are always an improvement, but an entry-level HF rig, a HWEF, and WSJT-X is a great path of entry to the HF bands. I’ve gone on about this earlier, but there is nothing in-stone about needing to start with CW or SSB. Hams can get on the air, interact with DX, and get some good contacts in the log. I see nothing wrong with that.

Compact, Broadband, Efficient: Pick Two

In the HWEF and 9:1 design cases the user is giving up efficiency for a more compact, more broad-banded (lower Q) device.

The HWEF, thanks to its resonant radiator, is somewhat more efficient, but the price is being paid for getting wide frequency coverage on a single radiator. Some designs find ways to better balance the equation by sacrificing some bandwidth and band flexibility to increase efficiency. One QRP design I use is the PAR 102040 Trail Friendly. This design uses three techniques to get a three-band end-fed vertical into a single 41′ wire radiator package. Trick 1: It uses a trap to isolate the 20m half wave element from the 40M extension. Trick 2: It uses the characteristic electrical lengthening effect of the trap to keep the 40m extension (and overall length) shorter than a simple 40m half wave radiator. Trick 3: using the second harmonic of 20m to realize some usable bandwidth on 10m. The transformer is pretty much handling the design goal of representing a 3000 ohm feedpoint as a 50 ohm load to the rig. No additional trans match is needed if you have trimmed the 40m extension properly and are ok with the tuning points. It isn’t brilliantly efficient, but it’s not horrible.

Chameleon MPAS Lite – Mini Review:

In early 2021 I picked up that Chameleon MPAS Lite and wanted to give it a run as a portable antenna system for POTA. This unit is extremely compact and is comprised of a ground spike, a un-un, a heavy duty stainless whip and 65’ of wire to use as a counterpoise. With the engineering triangle in mind I knew I was giving up a lot of efficiency for a very compact, very broadband system. And that’s what I got. It works well enough, especially if you are calling CQ and self-selecting stations who can hear you. I found that replying to anything but the loudest stations was a bad recipe for success. In a Chameleon forum I made the comment that these antennas aren’t good DX setups. I stand by that. It isn’t that you won’t work any DX, you would just work more DX more easily with a better DX design. For mid-range and NVIS work I think it is a solid solution. That assumes you are able to make the contacts you need to make. Also, watch the power rating because the un-un will get warm, and will fail under excessive power and duty cycle.

The MPAS system uses a 5:1 un-un design to feed anything from their very nice stainless whip, MIL Whip system, a longwire, or whatever conductive item you decide to use. The 5:1 takes a conservative approach to the non-resonant radiator problem, and a second transmatch (internal or external unit) is required unless you get lucky and dial in a 250 Ohm (or 10!) feedpoint impedance for the Un-Un. Chameleon publishes a perfect omnidirectional pattern for their antennas. That’s a good assumption for the operator since non-resonant systems are difficult to model accurately. Just assume your RF is going in all directions equally. Might as well! In practice I have made contacts and successfully activated a few parks using the MPAS Lite. Chameleon builds a beautiful and rugged product, and supports their users well. II feel like it is a good system and the user will get the best out of it by realizing it’s strengths and weaknesses.

One concern I have from following a few antenna forums, including a Chameleon product support forum, is the number of users claiming to have “resonant” solutions. An actual resonant radiator would provide a terrible match with a 5:1 un-un. What users are doing is finding a radiator length that presents a 1:5 feedpoint impedance to the CHA transformer so the radio sees 50 ohms(ish). That approach may be usable on that band with no additional matching, but is likely to be worse on other bands.

Another constant question on these forums regards radials and counterpoises. Strangely the solutions discussed are often none, one, or several short radials. All of these are poor solutions. However, when the central design concept is to never be resonant, not require radials, and use almost anything as a radiator, I don’t know what a good solution looks like. The Chameleon counterpoise kit is 65′ of very hunky insulated wire and can help you play with the counterpoise dimensions/layout and maybe help in finding a match. That said I feel like users are trying resonant counterpoise lengths and I think that does more harm than good. With a single counterpoise, stick to the game plan. Why make the two impedances different?

The Chameleon 50′ RG-58-ish feedline with a ferrite bead choke on one end is a decent way to control the stray RF. And it is necessary. Every time I have used it I had to control RF that wanted to energize the radio’s earth ground.

The best application I have seen for these matching units is Chameleon’s own Tactical Delta Loop which uses the CHA as the feedpoint in a system where 5:1 isn’t a bad design value. I will be cobbling a test setup soon out of various Chameleon and Wolf River parts.

Wrap Up

If it sounds like I am down on end-fed designs, I’m not. They have a proven track record and get hams on the air. What I would like to get across is that I hope ops get some time on other designs. Building a nice 1/4 wave vertical over a good set of radials is very easy and cheap. Think of a it as a single-band DX Commander style build. I think it is worth the time and small expense to see how a resonant design works and maybe make a few on-air comparisons.

If you stuck with this post I owe you a pint. I don’t write these to be concise blurbs. I like to compose my thoughts on these topics and I figure sharing it is part of the experience. Let me know what you think! Reply on the blog, or look me up on QRZ and drop me an email.

Get on the air, and always have fun. 73, Pete N1QDQ

Why So DGTL?

The current explosion of HF weak signal mode users, coalescing primarily around FT8/FT4, has caused a bit of a rift in the ham community. I don’t think the rift is that big, but the rifters are pretty vocal in telling other hams how much they don’t belong on the air.

I intended to formulate a Pro/Con list, but I don’t want this to be a contest (or con-test). I also don’t want to explore the negatives. Plenty of people are doing that 24/7 and somehow seem to enjoy (?) it. This is a list of things that make each type of communication interesting and unique (for me). I’d rather look at it that way because that is how I feel about it. I want to enjoy all that ham radio has to offer. That requires being open to what is positive about every opportunity.

So here’s what I find attractive about FT8-style* operation:

  1. The Analog Internet Nexus. In conjunction with PSKReporter, RBN, and tools like GridTracker, it provides a near-real-time propagation indicator. I can set up for a few CQs, check PSKReporter, and see where I am being heard, with my relative S/N. Along with showing me where I might expect a reply, it gives me an idea of the difference between what I am hearing and who might be hearing me.
  2. Instant and visual split operation. WSJT-X makes setting split very easy, but only if you use the waterfall display. (I believe many users don’t, causing that crowding between 1300-1800hz). Shift-Click to position your transmit frequency in a different spot, and get out of the pileup of stations calling on the CQing station’s transmit frequency. Since WSJT-X decodes the entire bandpass, you can test this at will. 10 minutes with the WSJT-X manual will improve the experience 100x.
  3. Constant Global Activity. It’s pretty shocking, actually. Day after day if I just looked at the CW or Phone sections of the HF bands they may look dead, or occupied mostly by big signals. Often there is a big hump on say 20m at 14.074MHz. In my experience it is unprecedented to have this type of activity acting as a global beacon. These digital segments are in use at all hours of the day and when the band opens those ops will be there.
  4. Built for Low Power Ops. Being able to work down to -24dB is a great equalizer for lower power stations on less-than-spectacular antennas. I see all kinds of amazed reactions from mostly newer hams on QRP-focused boards like the Icom IC705 FB group, and I can only imagine how amazed they will be when actual good band conditions start arriving. I’ve worked 10,000km on 10W into a basic vertical antenna on FT8, during conditions like SF=75, SSN=15! No solar tailwind there. For reasons I will get into somewhere else, a non-directional antenna is really only sending a tiny slice of its output toward the other station. Being able to work deep into the noise floor makes the most of that tiny slice.
  5. Perfect for casual operating. Letting WSJT-X decode while I am making dinner, or doing other chores, lets me come back and see what stations are in play at my station, on my gear, at what strength. I can take 15 minutes, scan the waterfall, and either chase a few stations or find a spot to call CQ. Obviously I can also do this for hours, but if I only have small gaps to focus on the radio I can still make contacts this way.
  6. Good operating practices are rewarded. Far from being a “robot mode” FT8 gives the operator a lot of information if they are willing to look for it. It allows you to scan for momentary openings, dig out weaker signals, find opportunities to use split, and otherwise be creative with the information presented by the waterfall and the decode window. I recently made a few contacts to JA from Rhode Island with stations that showed up for less than 5 minutes, and then faded out. Tools like GridTracker and JTAlert let you watch for those stations in real time. I’ve come close to working deep into northern Canada (VE8) in this same manner. I’ve also seen the big Saudi or Kenyan stations about 20 times and never made the contact. Surfing the waves of fading/swelling conditions is a technique I learned on CW over 25 years ago.

*FT8-style means computer-assisted digital modes, like RTTY, even. 2FSK is still FSK, folks. Get over yourselves.

OK, that was a rollercoaster of unbridled optimism. I’ll now make similar points for analog modes:

  1. The experience of listening to radio is one of life’s great joys. The key word is listening. I like quality in a QSO. Rarity and quantity have never been my game. I enjoy finding and working DX, but have never applied for or sought any awards. Listening to a quiet band for a weak but copyable signal (usually CW) just above the noise, replying to a CQ, and having a QSO (no matter how short or perfunctory) is a real pleasure. I’m not too hung up on where that other station is.
  2. The Social Component. I have worked plenty of stations, mostly SSB, where the QSO is call, report, name, QTH, and 73. Nothing wrong with that. It’s not much more of a proof of concept than a FT8 contact, but you are making verbal/code contact. Neat. Occasionally though I end up in a real rag chew, with a personable operator, and it is a great experience. I have to make sure I am in no hurry, because I have had a few that ran for a long time. That is ham radio delivering on what I would call the classic roots: Two or more operators having a chat. Lovely.
  3. A true leisure activity. My process of slowly scanning a section of a band, giving even the weakest signal a chance, tweaking my rig’s controls in an attempt to pull that signal out of the noise… it takes time. I might make one contact in an hour. I might make none. I have done some salmon fishing, and it is similar. My salmon fishing mantra is “it’s fishing, not shopping”. If you don’t enjoy the process of fishing you will be having a lot of bad days. If you have a catch, that’s great, but you are still fishing.
  4. Skill Development. The skills necessary to operate successfully on the ham bands are still best, IMO, cultivated with analog operation. Just the habits of ensuring your frequency is clear, or listening to and identifying neighboring stations, or learning the band plan and using it… they pay off whether you are talking to someone on 2M simplex 500 yards away, or making an APRS contact through the ISS, or bouncing a signal off the moon. It might be analogous to driving stick shift. I think you get a better learning experience when you engage the fundamentals as completely as possible.

So that’s a quick, stream of thought run through of how I see the allure of both “new school” and “old school” ham radio. It’s all out there to be done, and it’s all good. I hope to see or hear you on the bands. Pete N1QDQ

21st Century Schizoid Ham

This post is an attempt to bring my thoughts on the future of ham radio into focus through the lens of computerized digital modes. Last week I poured out a lengthy brain dump regarding digital modes, specifically FT8 and it’s associates. Three posts ago I went on about the evolution of communication modes. What I am focused on today is how radio hobbyists have embraced (or fought) the march of technology.

When radio was born the primary technologies being leveraged for more reliable communications were output power, antenna design, and modulation modes. That this is a fair description of the challenges faced by radio operators today is a testament to how strong the foundations of radio communications are. Just over 120 years ago Marconi was giddy at sending a coarse unmodulated signal across the English Channel. About 2 years later he sent a Morse Code “S” over the North Atlantic and it was received. From that primordial ooze advances in radio technology have been a succession of technological refinement and hybridization. Better tubes led to early solid state devices, led to (begat!) better solid state devices, led to the microprocessor and so on.

And that is how it should be. Most hams today use high tech in at least some part of their signal chain. The lack of enthusiasm for drifty VFOs and heavy transformers bears this out. Some of what I see in the commentary from today’s “old guard” is essentially a semantics debate, without the debate. Some want the technology used only inside their transceiver, but not “over the air”. Some are fine with one digital mode such as RTTY, but not another like FT8. Both employ a form of Frequency Shift Keying (FSK) and both rely on a machine to encode and decode text messages. This concept of using machines to do what the human body can’t is as old as the Stock Ticker. In the case of Radio Teletype (RTTY), could you learn to decode a two-tone encoding scheme by ear? Yep. Could you do it at RTTY speeds? Nope. We utilize a machine. That machine is now primarily a computer.

RTTY was first an analog process which gradually became computerized. Over the years the mechanical devices became museum pieces. One reason is electromechanical devices are entropy attractors. The wear out and break down and require mechanical repairs. Maintaining them means ready access to parts and service documentation. Certainly there are operators of mechanical RTTY terminals on the air, but they are in the minority (and I’m being generous). The era of “no serviceable parts inside” has mostly won the day here in the 21st Century. That’s a fact. I saw the transition from analog to digital firsthand as my father and grandfather both made their livings in electronics.

From the 1950s through the 1970s my grandfather owned and operated a TV and Appliance shop. He sold and repaired TV sets and radio consoles. His world was one of SAMS Photofact and a tube caddy and kept those TVs humming with his experience and some simple test equipment. The day the new TVs came with no service manuals he started to close his shop. That was almost 50 years ago. He saw the writing on the wall, and his mentality was fixed on keeping those sets in service. He was a product of the immigrant experience during a global depression and great scarcity. You did not throw things away. You repaired them until they were more valuable as parts, which you used to repair another set. The era of disposable consumer technology was his exit ramp from the business. He never changed. The world did. Far from being a luddite, he was an early adopter during the birth of technologies we take mostly for granted today. From the 1930’s onward he was right there jumping in on the birth of electrification, radio, television, and photography. He was my ur-geek.

As a child of a very different time I have been free to live in a world of unbridled futurism. I came of age during a great social awakening with social and technological changes happening at a blinding pace. I wasn’t so much dreaming of the future as I was living it. The space race fascinated me the way kids today get into dinosaurs or pokemon or whatever. I’ve been using actual computers since 1978. Before that I learned to do four function math on a Heath-Kit Hex Programming Trainer with NIXIE tube display. All I have seen is a steady drumbeat of miniaturization, automation, and leaps in electrical efficiency. I type this on an ultrabook weighing about two pounds and it the performance is fantastic. It draws about 1/50th of the power of my first PC-XT. The USB chip has more processing power than that 8088 had.

See, I’m digressing. I think you get the point. I will now focus!

My concern about the future of the technical evolution of ham radio has to do with the resistance to technical advances by some of the loudest voices in ham radio. And I do mean loudest. I like big antennas and I can not lie. You other ops can’t deny... But there are other ways to get the job done. In the case of FT8 we implement commodity computer hardware to expand the usable dynamic range down below what can be done with the human ear. This is not even all that high-tech. It is actually an extension of rather old tech, adapted to low cost CPU hardware.

Today’s hams largely operate in an early 20th Century manner, using 21st Century devices. We are often using a computer to emulate discrete component technology or even pure analog technology. That computer is often a “black box” running code we don’t understand on devices we can’t physically interact with. Most of this computerization isn’t a breakthrough, it is “re-platforming” of existing tech. While a boon to the operator it doesn’t seem to be equating into higher tech knowledge among the ham community. A survey of our publications, chat forums, and social media platforms show a continued focus on what should be Radio 101 topics: basic antennas, basic tuned circuits, basic inductors, the trans-match, the audio signal path… Yet I continue to see new hams struggling with the difference between rig control and audio, AC and DC, the concept of an IF, simple voltage/current concepts, and so on. One reason may be our teaching tools haven’t caught up with the pace of technology. Three-inch thick manuals in an age where bookstores are extinct might not be the way to get it done. #jussayin

At some point the practices and frameworks need to advance. We are doing ok, but we need to do better.

The Finale: I understand this is bordering on TABOO, but I’ll close this post with questions that I hope sum up my outlook on Amateur Radio as it waddles into the 21st Century:

Do our current band plans look like what we would draw up based on the technology we have at our disposal today?

As well, do our current band plans create a chilling effect on the adoption and implementation of new technologies?

Are we so anchored to the past that we have limited our ability to reach forward?

Can we create better technical standards, better education materials, and move toward better informed hams who can help move the pursuit forward and step beyond appliance operation?

I’m not pointing fingers (maybe a little). Those are questions I often ask about myself. I am largely an appliance operator. I build a few kits when I have time, make my own cables, build basic antenna systems, and am dedicated to self-education. I lean on a foundation of electronics basics and I want to learn more. But I also want to learn better.

I am using the FT8 discussion as a backdrop because we should be able to conceptualize how important decreasing the power and antenna requirements for ham radio is to the survival of the hobby. It is democratizing, and allows the ham radio experience to be enjoyed by the many. It also leans on tech that a 21st century ham takes completely for granted. If anything the challenge for today’s hams is adapting to the use of older tech that is used virtually nowhere else. The RS232 Serial Port is a great device, but try finding one on a modern computer. The urge to learn the technology is as strong as ever in the next generation of hams, we just need to lay a functional understanding of radio tech over that urge. That is difficult if the tech we are teaching and using is not current.

PostScript: I don’t see modes like FT8/JS8 as an end. I hope they are the foundation for more versatile and robust modes to come. We will always have SSB and CW and modes like RTTY. But unless we can get behind what the future holds we run the risk of being a bunch of radio-wielding Civil War reenactors. And one day we might show up to the battlefield and see a big CLOSED sign. Nobody wants that.

Lightweight Antenna Roundup – Episode 1 -The PAR TF 402010

My first HF transceiver was a Ten Tec Triton IV with analog dial, followed by a TT Argo, A Yaesu FT101, and then one of the original, “shack in a box” radios, the ICOM IC706 (and later a MKIIG). For reasons mentioned in the previous post on this blog I moved on to running a Yaesu FT-857D, a FT-817ND, and an original FT-817. That gear, along with an assortment of V/U/SHF equipment for VHF contesting, and various FM HTs, was the basis of my experience with transceivers. I got to know what I liked and what I didn’t. The Triton IV was the most fun CW rig I have ever used. The receiver was easy on the ears, the QSK was fantastic (like listening to yourself on receive), and it was fairly portable. The IC706 rigs were more versatile, covered more bands, had more power, and included at 20/70cm all mode. And it wasn’t a bad all-mode. After seeing my gear pile dwindle to almost nothing I started putting together a new station. I was looking for something fun and portable and found myself looking at the uBitx. I worked up one kit but just felt like it was not going to handle what I wanted to do. Then Xiegu released their G90 and that radio got me back on the air for over a year. It’s a great rig, but it came with the question of what antenna to pair it with?

Having used wire dipoles and a few commercial multiband verticals for fixed operation, and hamsticks, base loaded whips and other compact designs for mobile use, I had something to refer back to. My experiences with those mobile antennas was not great. Yes they work. But no, they are no comparison to a full size antenna. I used those in both fixed and mobile setups and I was happy for any contact I could make. To be honest hey were not good performers on either transmit or receive. Once band conditions improve you will be able to regularly work some sweet DX at 20W into a 20M hamstick on a mag mount. Now is not that time. If you can’t put up a perfect antenna, at least try for the least-bad antenna you can manage.

It turns out that while I was off not paying attention to ham radio equipment there has been an explosion in “compromise” designs like end fed wire antennas and they can be built/purchased to suit anything from an altoids-tin rig to a legal limit linear. The development of these antennas revolves around two fundamental designs: A half-wave radiator with a 49:1 un-un at the feedpoint; or a 9:1 balun feeding a non-resonant wire. In practice the use of a counterpoise is either unnecessary or misunderstood. From an optimal antenna standpoint these designs leave much to be desired. The matching unit is being asked to make a large impedance transformation into a rather blunt radiator, without the typical array of ground radials or even a counterpoise of any kind. However, from a real-world standpoint these designs are proving to be both effective and easily erected while also being cheap to build. That is rare.

After perusing many different designs I purchased the PAR 402010 Trail Friendly. It is advertised as covering three popular bands with no ATU, and it is light enough to be supported by just about any support. This is a design antenna with a history of being made by several builders and Vibroplex now markets them with the PAR branding. It features a 41′ lightweight insulated/stranded wire radiator with a 40M trap to make it resonate on both 40m and 20m, and it will also load on parts of the 10m band. The lightweight build still feels sturdy, and has proven durable over a year of regular use. The tip of the radiator can get mashed up a bit, especially if you have a mast collapse. Note my use of a heavy wrap of electrical tape at the tip of the mast. It helps with setup and fits in the collapsed tube.

About that mast… (12M Spiderpole Mini-Review Alert) At the same time I was searching for antennas I found another member of the Vibroplex line, Spiderbeam, and their 12-Meter Spiderpole. Often nicknamed “the beast” It’s built like a tank and can hold up much more than this little low-power wire vertical. Interestingly they do fit like they were made for each other. “The Beast” isn’t a backpacker pole unless you are a glutton for punishment or take your Cross-Fit habits onto the trails. It isn’t terribly compact, and it isn’t light. What it is is a borderline overbuilt 41 foot weatherproof antenna support.

The Spiderpole is overkill, a luxury, though a versatile luxury at that. It is a big, heavy telescoping mast and needs to be well secured at the base. It has more wind load than I guessed and exerts a lot of leverage on that base section, so you want it to be well secured while avoiding hard points where the fiberglass tube wall could fail under a sudden or heavy wind load. The upside is you get a 41′ vertical skyhook. Nice. It also shrinks the footprint compared to what you need for a sloper or inverted vee and allows you to work where there is no overhead support. I am surrounded by beaches, so something like this lets me operate from more locations and not be limited by the presence/absence of a large tree(s) and I create less of an attractive hazard for lookie-loos. It appears to be a law of physics that as soon as you put up an antenna some random mammal will walk directly into it within 5 minutes. All you can do is pad the odds in your favor.

Very Vertical

I was curious how this antenna would perform, especially compared to a 9:1 unit I had built and used on this same Spiderpole support. Mine is the basic trifilar design over a T200 core. The 9:1 works, but I always feel like I am working “up-hill” with it. That perception is based on ability to work stations I hear, and the signal reports I receive. There are worse options than a 9:1 into a chunk of wire sized to a convenient non-resonant length, but it feels very lossy in operation. When I first rigged the PAR I had my doubts. Rated at 25W SSB it isn’t much to look at. The matching unit is smaller than a fun-sized candy bar, the wire looks like overbuilt dental floss. Once I attached it to the Spiderpole and got it fully extended the ultralight wire It seemed out of balance being supported by “the beast”. Happily I was more than surprised at how well it performed. I observed much more parity with the stations I was hearing and working and logged several nice stretches of contacts on both FT8 and SSB. I was using it with both a Xiegu G90 and a Yaesu FT-991A, and aside from needing to watch the power output it did what it says on the tin. Three bands, no waiting. I don’t hesitate to set this up for a quick evening of casual operation since setup and take down require about 10 minutes each.

Here it is lashed to a deck railing in my back yard (or “garden”. You know who you are). If I was expecting gusty conditions I would have a 4-way support at the top rail and the base. In calm conditions the bongo ties hold up just fine. Just use as many as you dare. This thing puts a lot of stress on the support system.

When erected the matching unit sits about 3″ off the deck.

Technical Aside: These end-fed matching devices are indeed lossy. You don’t need to break out a calculator to know this. All you have to do is look at the designs for different power ratings. The size and number of the ferrite toroids (typically 43-Mix) need to be increased to withstand the increased field density of each higher power rating, and the heat that comes with it. A good portion, perhaps as much as 30%, of the power making it to the matching device gets siphoned off as resistive/heat losses. [tl/dr YOU ARE MAKING HEAT NOT ERP] But hey, you know the setup is a compromise going in. That compromise is lower overall efficiency in exchange for ease of setup and portability. I found that going from 5W to 10W output caused a sizeable step change in the contacts I was able to make, but that is to be expected, since my ERP was probably going from 3W to 7W. Certainly you can make a lot of contacts with this antenna, but you will probably be be several dB down from where you *might* be on a more efficient antenna system. The upside is that you can get on the air quickly with not much fuss, which translates to more time operating and less time reading long winded blog posts. But I digress.

A Phalanx of Bongo Ties and Clamps

One big question with “the beast” is how to support it, and one of those lightweight drive-on flagpole mounts is not likely to get it done. I currently use a phalanx of bongo ties, woodworker clamps, ratchet straps, and U-Bolts. None of them are perfect but I can lash it to a variety of improvised bases. I’m thinking a 36″ tubular support welded to a 2″ trailer hitch is about what it would take to have real peace of mind with this thing while operating car-portable.

Wrap Up: My feeling about this antenna has done nothing but improved each time I deploy it. I feel like this particular design gets overlooked. That’s a shame because it is a solid performer. It hears very well, is easy to tune, and I am always surprised at how well it works. We can hope all we want to have a low loss resonant radiator over a dense field of copper radials, or a big dipole/doublet/windom/curtain a half wave up on solid supports, but it seems that what many/most hams typically need is a way to get on the air under sub-optimal conditions. We also want to be able to actually operate once we get set up. What I would love to see is a 200W CW Rated version with the same 41′ design. Right now I guess I have to build one. Vibroplex has a potential two-fer on their hands if they can match a 41′ triband wire vertical to their affordable heavy-duty 12m Spiderpole. That opens it up to running CW or digital/RTTY at a full 100W and having a solid safety margin at the feedpoint.

I hope this was informative, or at least I hope you had a good nap. 73, N1QDQ