Author Archive

Rothamel’s Antenna Book: An Authoritative Source

As an academic researcher, the term “authoritative source” is reserved for works deemed to be the standard by which other scholarship in an area is judged. As a U.S. ham, I’ve purchased the ARRL Antenna Book (both new and used) since I’ve been licensed. Good reading and reference. It’s been a go-to document not only for me but for many State-side hams. There is a new Sheriff in town.

There’s a new sheriff in town for antenna handbooks!

I’ve read about Rothammel’s Antenna Handbook in other publications—Practical Wireless and RadCom, for instance—but it was in German. Alas…Ich spreche kein deutsch! Since 2019, there is an English translation.

On eHam, there is but a single review. James AD0YO says, “This book is amazing! It should be on the desk of any ham interested in antennas. And, that should be all of us. The first 270 pages cover theory. The rest cover all types of antennas.” OK. James loves it. What about others?

A website I often read, the Reeve Observatory near Anchorage AK, has a review: “The information in Rothammel’s Antenna Book appears to be taken from both amateur and professional literature and patents from around the world. Having this book generally will save readers considerable time when looking for details on a particular antenna type or for ideas on what antenna to build for a certain
application. Each chapter has an extensive list of references, so it may be possible to get to the original source document.”

The popular commercial vendor in the U.S., DX Engineering, carries this volume (although out of stock as I write this). It also has only a single review. Two years ago, Juan (no call) wrote, “This is a 1,600 (page) treatise on Antennas! It is more theoretical than the ARRL Antenna Book, but quite less than John Kraus classical textbook. It has a ton of data and practical information. It is a very good comprehensive reference book on antennas.” Another onesy but rave review. No gotchas yet.

Another source I enjoy, Radio User magazine, had this announcement. “The famous Rothammel’s Antenna Book is now, at last, available in English. At the 2019 Hamvention, DARC announced the availability of the wonderful Rothammel’s Antenna Book into English. This translation is of the 13th edition of Rothammels Antennenbuch.” Now I recall my friend, Scott K0MD, telling me that he picked up a copy of this impressive book at Hamvention. Great international reviews. A close friend who bought it and is impressed. Wow! This is getting close to my wallet.

The standard ham radio antenna reference.

James AD0YO, eHam Review

Rothammel. Who is (was) this guy? Wikipedia advises “was” is unfortunately the correct tense as he is now a Silent Key (1914–1987). After reading a short biography on Rothammel, it strikes me that he would be in league with Lawrence Cebik W4RNL, a professor of philosophy at the University of Tennessee in Knoxville, long revered for his antenna work and writing. From the German Wiki, translated to English by Google Translate:

“Rothammel had been a radio amateur since 1932 with his call sign “DE3040/L”. During World War II he served as an Air Force radio operator. Little is currently known about his stay after the war, except that he settled in the Soviet occupation zone – the later GDR.

Karl Rothammel

After the war, he initially worked as a guest and farmer before moving to the postal service of the GDR for ten years. At the post office, he looked after the radio and television transmission systems. After ten years, Rothammel moved to the information and documentation center at the radio equipment factory Stern-Radio in Sonneberg, which later became VEB Stern-Radio Sonneberg . He did this job for 25 years until he retired. Since 1954 Rothammel was active as a radio amateur under the call sign “DM2ABK”, since 1980 under the call sign “Y21BK” or “Y30ABK”.

In addition to his professional activities at the post office and at VEB Stern-Radio, Rothammel was a long-time club station manager in Sonneberg, a member of the examination committee in the Suhl district and an authorized person for the radio performance badge in gold. For five years he wrote articles on VHF topics for the magazine Funkamateur. In addition, he contributed as an author to various publications on the subject of radio, for example the books “Ultra Short Waves”, “Practice of TV Antennas Part 1 and 2” and the “Handbook for Short Wave Amateurs”, etc.”

I ordered a copy of the 1st Edition English translation, copyrighted in 2019, directly from the DARC. Easy order. It took several weeks to arrive via DHL and final delivery by the US Postal Service. I was researching HF loop antennas for an article. I was thrilled at the depth of coverage and the detailed citations and patents included. It greatly helped me organize my thinking on how to improve the design and deployment of an HF horizontal loop antenna. More on that article in the near future as it nears publication in Practical Wireless magazine.

Here’s an illuminating example on a relatively unknown niche type of antenna. Here in the States, due mostly to posts on QRZ.com, the reader would conclude that fractal antennas were wholly invented by Nathan W1YW. As the sportscaster Lee Corso is fond of saying, “not so fast!”. Look at what I read on pp. 948-9:

Rothammel’s Antenna Book entry for fractal antennas

In the same year (1995), two researchers filed patent applications for something they called, fractal antennas. In May, Dr. Carlos Puente in Spain filed his application which was approved in 1998. Later, in August, Dr. Nathan Cohen filed his patent application in the United States but it was not granted until 2000. As Rothammel states, the priority goes to the first filing. This small point may only matter on legal issues but it’s both enlightening and historically correct for the amateur radio community to know that there were indeed two “inventors” of the fractal antenna line. Lots of good stuff like this in the Rothammel Antenna Book.

So does this book replace the need for the very popular Antenna Handbook by the ARRL? Not at all, as the ARRL book is geared more toward pedagogy and far less on being an authoritative reference. Rothammel’s book, for instance, does not include supplementary software, data files (antenna models, propagation projections, etc.), and such. Editions of the ARRL book do overlap greatly across adjacent editions so that’s caveat emptor for the buying ham. Me? I have quite a number of the ARRL Antenna Handbooks, as well as most things written by Joe Carr and other antenna scholars. Now, the Rothammel’s Antenna Book is on my bookshelf right beside them. I won’t have a problem finding it at 1,600 pages in length!

I can add my own superlative review to those quoted above. It’s not been fully read thus far but the spine and pages are certainly creased quite a bit! I’ve read deeply on loop antennas and through the theory section. It’s now my authoritative resource for amateur radio antennas.

Take a Long Hard Look at Our Community… An Editorial by Onno VK6FLAB

This post is to lift up the recent editorial published on eHam.net by Onno VK6FLAB in Australia. His long running podcast, Foundations of Amateur Radio, is one of my favorites. I listen to it every time it drops in my podcast catcher. I’m slowly making my way through the previous 500 episodes. Not one has been disappointing. Onno has recently taken on the scourge of social bullying in our hobby. It affects everyone, not just the bullied.

Once the collective atmosphere of a group, however large or small, has become contaminated by the blind or even oblique tolerance of bullying behavior by even one member of the group, it is there for all to be potentially subjected. The tolerance of bullying will precede new members and succeed former ones. While “bad character” may be the original culprit, the social norms of the group become the active agents of that tolerance of it in the future.

To be clear, our community is a welcoming environment, filled with hope and joy, but there is a small rotten element in our midst that we need to rip out root and branch, much like we would if it was deliberate HF interference.

Onno VK6FLAB on eHam.net

Onno’s essay at eHam.net is available through the link below. I encourage you to read it with an open mind as to your own behavior and those with whom you associate. Being bullied through social media tends to begat your own negative response. I wish I could state that I have never responded in that way. But I cannot. My commitment is to reduce any such behaviors in response to those engaged in bullying of me and to defend those being bullied.

As a professional sociologist who has studied social movements, almost always involving violence, I wish that I could offer a complete answer to the problem. But I do know that Onno is on the right track: tolerance of the problem will only exacerbate it. If you value the amateur radio hobby, it is worth your time and consideration to see what Onno has to say.

To read Onno’s editorial at eHam.net, click HERE.

Visiting Again with the Denby Dale Amateur Radio Society

Have you ever been invited to visit with a group of radio amateurs and just felt like you’d dropped in at home? I’ve had the pleasure of that a few times. One of those groups is the Denby Dale Amateur Radio Society in England. Their Chairperson is Nick Bradley G4IWO. He’s invited me to natter about with the DDARS several times over the past couple of years. Last week, I spoke to them about my RadCom articles with Dr. Scott McIntosh that appeared this summer.

The talk is now on their Youtube Channel below. I hope they get back soon to meeting in Pie Hall, where they are served pie and peas. After all, Denby Dale is the home of the world’s largest meat pie! If the pie is as welcoming as the group that typically meets there, it’s very good indeed!

Frank K4FMH on Radical Alternatives to Sunspot Prediction

Kicking-Off the HamSCI Year of Seminars

It was an honor to be asked by Nathaniel N2AF to kick-off this year’s series of online talks last week. We are kicking-off another football season so I actually got to play in this one! There were 60 or more in online attendance and several who sent in notes that they couldn’t make it but wanted the link to the video. And…great, great questions from the audience!

Here’s the announcement from over at the HamSCI.org website. The link to the Youtube video is at the bottom of this post. Comments and thoughts are welcomed! I’m good on QRZed.

Seminar: Revolutionary Alternatives in Sunspot Prediction

Thursday, August 18, 2022 – 23:45

Thursday, August 18, 2022 – 23:43

Submitted 2 weeks 3 days ago by w2naf.

Dr. Frank Howell K4FMH will present a seminar based on his two-part article in the July & August 2022 issues of the Radio Society of Great Britain’s RadCom journal, written with Dr. Scott McIntosh of NCAR in Colorado, titled, “On the Cusp of a Scientific Revolution?” The seminar includes the latest theory construction and model estimation. The seminar will be held on September 1, 2022 at 4 PM Eastern (2000z) during the weekly Solar Eclipse QSO Party Zoom Telecon. Frank is Professor Emeritus at Mississippi State University, Affiliated Faculty at Emory University, and a scientific member of HamSCI.

Abstract: Sunspots are the Dow Jones Industrial Index for hams. We are faithful to the sine wave model of the approximate 11-year cycle with the official NASA/NOAA predictions being our Holy Grail. I’ll address the following issues. How did we get to this sine wave conception? How do scientific paradigms compete and change? A new competing paradigm by the McIntosh team has been proposed. What’s new? What’s both the theoretical and empirical basis for this Kuhnian revolution in predictions? For Cycle 25, I’ll compare the official NASA/NOAA versus McIntosh team projections of SSNs and how they are constructed. I’ll also show how they compare to observed sunspots in the Cycle. Can we now better predict the underlying phenomena driving the amplitude and transition of a cycle? This model competition may well parallel the Newton-Einstein paradigm clash a century ago where science hung in the balance while solar eclipse photo plates were taken in Brazil and the Island of Principe. Now, we can follow along and see: will there be a scientific revolution in sunspot prediction?

Link to the Youtube video:

A Good Use of an Old Baofeng HT

The old Baofeng HT (UV5R) is the butt of many jokes these days in amateur radio. But right after their introduction, they were the “Xiegu HF rig” of the moment: they mostly worked, were cheaper than many similar products, and hams just had to explore them!

I bought a few, kept one, but gave them to new hams. Heck, I even purchased a case of Baofeng’s to supply the new amateur radio club in my home county of Washington County, GA. They would charge them up, program them for the new repeater, and gift them to newly licensed Techs in Sandersville and there abouts.

What happened to the one I kept? Well, if you have a minute, here it is.

The Jackson MS area had fallen by the wayside in terms of APRS digipeaters. But it really sucked by not having any iGates. A fellow ham who was head of Security at an area hospital installed an iGate serviced by backup power as part of their EmComm effort. That was fine…until the IT team monkeyed with “odd” IP connections and just cut Internet service to it periodically. The turnover in IT kept the Security Head (the ham) busy renegotiating service behind their firewall. So he eventually got them to put it on the guest WiFi sector and it’s been serving the area reliably ever since.

APRS-Direct visualization of APRS system in Jackson, MS area (inset shows K4FMH-10 iGate footprint.

But N5DU and I led the effort to add more digi’s in the greater Jackson area, donating ones to the Vicksburg Club, a tower east of us that the manager (also a ham) gladly installed, a node at a nuclear power plant at Port Gipson, and one down I-55 South near Crystal Springs. But only one iGate to serve them really got in the way of educating the other digi managers to configure the right number of “hops” to effectively get to an iGate.

So I used my remaining Baofeng HT with a small footprint PC (Dell OptiPlex 160 Tiny Desktop, bought for $40 shipped via eBay) and a software modem to create a second iGate in my home (K4FMH-10). As the picture from APRS Direct above illustrates, it’s in the large footprint of the JARC digi installed on a water tower in Madison, MS to the NW of my QTH on the Barnett Rez. (See inset of my iGate’s estimated footprint by APRS-Direct. No, KI5JCL-9 isn’t riding a horse. He just has a sense of humor!)

K4FMH-10 iGate working away to “gate” just the packets from the W5PFC-1 Digi some 3 miles away.

It’s stored in the bottom of a builtin cabinet in my small library / printer closet adjacent to my 2nd floor office. It’s 3 miles from a nearby APRS Digi maintained by the Jackson ARC (my friend N5WDG maintains their repeaters and other digi devices). And, it sits in the supplied Baofeng charger. For over 2 years, working faithfully. Until it didn’t. And that’s the focus of this story.

The higher power battery is a slim-line model. I thought that would be good for this little iGate-robot. (See the picture on the left.) And it has been.

Bobby KG5TGT later added a 2-way iGate to the Southwest of Jackson. It covers several Digipeaters on that side of town: the JARC’s 2nd digi on a broadcast tower, Vicksburg’s Digi (that N5DU and I donated), and the monster on a tower at the nuclear power plant outside of Port Gipson. FB all the way! Until this happened.

Baofeng battery expanded rapidly!

Yep, over a day’s period, the 2 year-old high power battery (Baofeng marketing-speak) hit it’s outer charge limit and expanded several times over the slim size that it was…well, the day before!

All this happened while I was in a recording session for the ICQ Podcast. Unbeknownst to Martin M1MRB and my fellow Presenters, I simply ordered a replacement on Amazon that was delivered in 2 days. The K4FMH-10 iGate was back shipping packets into the APRS network.

The moral? Oh heck. Just check your batteries periodically. While I thought I had, this could have produced a fire. Fortunately, I’m in that small room every day for various things and I look at the iGate system. But this expansion occurred over a 24-hour period. I should take steps to create a more robust iGate unit. But that might mean I’d become Baofeng-free!

Do you have a Baofeng lying around, getting no use? Find a way to put it to some good. But do check the battery from time to time.

Part 2 of the “Revolution” Article on the Sunspot Cycle in August Issue of RadCom

RadCom’s August issue contains Part 2 of my article with Dr. Scott McIntosh on the potential scientific revolution in understanding the cycle of Sunspots. This part contains more insight into the McIntosh team’s path-breaking theory of the Terminator Event and the factors that shape Cycle 25. The comparison of competing paradigms—here from the NASA/NOAA Panel’s declaration of a Cycle 25 prediction without any disclosure of methods or theory used versus the McIntosh team’s peer-reviewed papers—is likened to the one a century ago between the classic Newtonian view and the upstart Einstein’s Theory of Relativity.

Who now reads Newton for science, except for history?

Howell and McIntosh, RadCom, August 2022

As the history of science shows, it was the upstart Einstein challenging the classic paradigm of Newton who brought the newspaper headlines, “Revolution in Science.” We can watch monthly updates of this modern comparison in a special website discussed in our August article.

This part of our paper contains the forecast of the Sunspot numbers and the Solar Flux Index over Cycle 25. See the August issue of RadCom, the journal of the Radio Society of Great Britain.

“Revolutionary” Cover Story in RadCom July 2022

I’ve mentioned this work in various episodes of the ICQ Podcast as well as on social media in my Twitter account and now it’s published. Dr. Scott McIntosh and I collaborated since my original feature interview with him in Episode 332 of the the ICQ Podcast back in 2020. He paid a return visit with me for a follow-up feature interview by Martin Butler M1MRB in Episode 377 recently. The article by Howell and McIntosh, “On the Cusp of A Scientific Revolution,” is the cover story in RadCom, the magazine published by the Radio Society of Great Britain. Here’s the cover with a very nice photo of the sun and the ESA Solo satellite facing it. Kevin M6CYB, layout and design specialist at RadCom, put this cover together using resources from the ESAATG Media Lab, for Elaine Richards G4LFM, Editor of RadCom.

Elaine G4LFM is a delightful Editor to work with! As my readers no doubt know from previous posts on this blog, I served as Editor-in-Chief for Springer Media, a very large scientific publisher based in The Netherlands. So I’veb oo that side of the editorial desk for both journal articles and book manuscripts. Moreover, the untimely loss of her Technical Editor, Giles Read G1MFG (sk), added to her workload recently. But she handled all of that, plus her pending retirement, with the utmost aplomb. There’s no muss, no fuss in submitting a paper. No waiting for 6-8 weeks or more for the Editor to “maybe” get back to you. I highly recommend RadCom as a potential outlet for your work.

This is Part 1 of a lengthy and detailed paper. Part 2 is scheduled to appear next month, in the August issue. It’s not an elevator speech so be prepared to read it like you would read a schematic diagram. We think it will be worth your time.

There are some other great articles in this month’s edition of RadCom. Here’s a screen shot of the Table of Contents so you can take a look at both the regular columnists and contributions by authors such as Scott and me.

So what’s all of this about?

We place the current situation of significantly different Cycle 25 predictions of sunspots into the framework of how science works. I’m not speaking of which test tube or microscopic plate to use, for that involves the mechanics of each specific scientific field (Yep, I realize just how outdated those examples are but you get my point.) How does “science” as an institution work?

This diagram illustrates how Thomas Kuhn depicted “scientific revolutions” in paradigm change:

Model of Kuhn’s Paradigm-Change in Science (courtesy of Dr. Jessie Hamner)

We argue that understanding the solar cycle is in the model competition stage of this diagram.

Dr. McIntosh is the solar physicist. I’m not. But I taught philosophy of science, research design and modeling various scientific phenomena in obscurely named course titles like Structural Equation Models with Latent Variables and Spatial Analysis. I also edited and created a few journals in my career, too. Moreover, I’ve worked for NASA in their Commercial Remote Sensing Program at Stennis Space Center and managed peer-review panels in Washington, DC. So I’ve witnessed how this works in several fields of science, especially when I’ve been invited to reconcile disputes in funding or peer-reviews (e.g., integrated pest management).

When I interviewed Scott in 2020 for the ICQ Podcast, it was clear as a bell to me that the issues he and his colleagues were having in getting some of this “revolutionary” work published in solar physics outlets reflected a clash of theoretical paradigms. Pure and simple. It represents a competing paradigm attacking many of the anomalous findings (or lack thereof) involving the amplitude and cycle transition. Afterwards, he asked me to read a draft of a key paper establishing the linkages between the Hale Magnetic Cycle and the Solar Cycle in which I made voluminous comments and suggestions on the data, modes of analysis, and how to deal effectively with reviewers as a former editor. I’m sure I made a number of “rookie mistake” comments since I’m not a solar physicist, lol. But he was very kind to not mention those, only suggesting other sources for me to read and review.

When it was published, I was greatly touched to have received an acknowledgement for my impact on the final paper (see Scott W. McIntosh et al. (2020). Deciphering Solar Magnetic Activity: 140 Years of the ‘Extended Solar Cycle’ – Mapping the Hale Cycle. Solar Physics (2021) 296:189 (https://doi.org/10.1007/s11207-021-01938-7). Considering that this could be a seminal paper among those published by the McIntosh team that might precipitate a paradigmatic revolution in our understanding of the solar cycle and sunspot amplitude and the transition from one cycle to another, it’s an even greater honor to receive this acknowledgement outside my own field of science.

Scott and I have developed a close collaborative relationship and I’ve learned a lot from him and his published work. He is just a delight in “elmering” me about solar physics. But have no confusion: he’s the solar physicist and I’m the statistician and philosopher of science. We hope that through this collaborative paper, his team’s theory, models and data reach the wide audience that is amateur radio. We hams are one of the significant consumers of this slice of solar physics. But we decided that my expertise would help identify the paradigm boundaries of Scott’s new paradigm as well as some other facets of communicating outside of solar physics. Perhaps even within solar physics, too.

As we “shockingly” disclose in RadCom, the current NASA/NOAA “official” predictions for Cycle 25 do not release any of their methods or assessments to the public. (Insert record scratch here.) Yet, their forecasts are decidedly lower in amplitude than those published under peer-review by my co-author, Scott McIntosh, and his team of collaborative scientists. Amateur operators, however, view the official NASA-NOAA Panel predictions over the past several solar cycles are the Holy Grail source of sunspot activity. We’ve seen this movie before:

While Scott has published beaucoup papers documenting his team’s explicit theory of how these aspects of the sunspot cycle (as amateurs like to call it) work together, our RadCom article attempts to lay it out in comparison to those “official” predictions by the NASA-NOAA Panel. One team will ultimately be proven to be more correct as Cycle 25 matures; the one based upon Panel votes of “expert opinion” or the one based upon a peer-reviewed alternative paradigm.

Those who see SSNs as the critical daily index shaping their amateur radio operations will want to see which team is “right.” To facilitate this, there is a website where the NASA-NOAA predictions, the McIntosh team predictions, the average SSN over the horizon, and the observed SSNs for each month are published in clearly annotated graphs for all to see. No “smoke-filled rooms” where just a professional opinion is offered, but observable empirical data, updated monthly.

Hmm. I wonder whether I’d trust a team of physicians who just met in a conference room and voted to see if I had cancer (which I did in 2005) or a team of physicians who took X-Rays, MRI’s, blood samples and so forth to aid in their diagnosis and treatment plan. Which one do you think is more worthy of your trust? Well, it’s largely up to the observed SSNs and the two sets of predictions, even though one is formally devoid of a stated theory, isn’t it?

Here’s the money graph here:

Time-Series Graph of observed and predicted sunspot numbers from 2019 through 2024

As the reader can see, the McIntosh predictions (in black) are decidedly closer than the “official” NASA/NOAA/ISES Panel’s predictions (two different blue lines) to the actual observed smoothed sunspot numbers as of July 2022 (green lines).

This is not unlike how the educated world awaited a specific set of photographic plates from an eclipse to determine whether the famous Sir Isaac Newton or the (then) young, whipper-snapper Albert Einstein was correct about Relativity. That was how the Newton-Einstein debate was largely resolved. The McIntosh team has put it’s scientific reputation on the line with observable data, which is how science has moved over the centuries since its emergence in modern societies.

Who now reads Newton for science, except for history?
Howell and McIntosh, RadCom, July 2022
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You can find out more about Dr. McIntosh at NCAR (his research center), on Twitter, or by listening to the two podcast episodes I noted above on the ICQ Podcast website. In addition, Scott has given many talks to amateur radio clubs on this team’s work. Youtube is your friend here. I’m already scheduled for late July to talk about this RadCom article to the Denby Dale Club. If you’d like a talk on this to your club, feel free to email me and I’ll do my best to accommodate you. I’m good on QRZ.


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