Amateur Radio Weekly – Issue 305

Amateur Radio Weekly

Hams crowdsource ionospheric science during eclipse
Probing the ionosphere’s response to the 2023 annular solar eclipse.

A few photos of the new Elecraft KH1
The KH1 is even smaller than I imagined.

NASA tech breathes life into potentially game-changing antenna design
An inflatable device that creates wide collection apertures.

Get publicity for your club with a PSA
How to spread the word about Amateur Radio.

SSTV images received from the ISS
12 images were transmitted from the ISS during the 2023 verification test.

Is a compromise antenna efficient enough?
The antenna you put up always works better than the one you don’t put up.
Ham Radio Outside the Box

Backscatter on 28 MHz
Signals are being reflected back towards my location from some distant point.

Machine teaches Morse Code
The Instructograph.

Picking the best battery for portable Ham Radio
Lead Acid vs Lithium Iron Phosphate (LiFePO4).


High impedance amplifier for software defined radio
Converts Hi-Z (High Impedance antennas) to 50 Ohm.
Tech Minds

2M Yagi Ham Radio antenna that fits in a pocket
Designed for SOTA and versatile field use.
Ham Radio Rookie

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Amateur Radio Weekly is curated by Cale Mooth K4HCK. Sign up free to receive ham radio's most relevant news, projects, technology and events by e-mail each week at


I was happy to contribute an article to the recent ARRL Parks On The Air (POTA) book. This piece is based on my Pikes Peak mountain topping article that appeared in the June 2023 issue of QST. This book is a collection of articles about POTA from 14 different authors, each writing about a different aspect of the program. The articles are all easy to read and generally provide a first-hand account of how the author has experienced POTA operating. There is plenty of beginner information and operating tips sprinkled throughout the book. More experienced POTA enthusiasts will probably pick up a few new ideas as well.

The Table of Contents below lists the articles and authors, giving you a good idea of the material covered. The meat of the book is only 118 pages long and it is quite easy to read.

My piece covered the triple activation I did from the summit of Pikes Peak, combining POTA, SOTA, and the June VHF Contest into one mountaintop adventure. For POTA, the park was the Pike National Forest (K-4404). I’ve done this type of combo activation in the past, sometimes just SOTA + POTA or just SOTA + VHF Contest. This time I did all three.

The book is available directly from the ARRL or from the usual book outlets such as Amazon.

73 Bob K0NR

The post ARRL POTA Book appeared first on The KØNR Radio Site.

Bob Witte, KØNR, is a regular contributor to and writes from Colorado, USA. Contact him at [email protected].

Adios Symbol Rate Limit

The FCC will be voting on and will likely approve a Report and Order that eliminates the symbol rate restriction on HF data transmissions, replacing it with a bandwidth limit of 2.8 kHz. See FCC To Vote on Removing Symbol Rate Restrictions. The symbol rate limit of 300-baud is an obsolete way of limiting the signal bandwidth, created back when the data transmissions were predominately Frequency Shift Keying (FSK). It was a simple, practical way to regulate the bandwidth at that time but technology has moved on. The use of digital signal processing and efficient wireless encoding techniques require a better approach to bandwidth regulation.

A practical impact of this change is to allow higher speed protocols such as PACTOR-4 having a bandwidth of 2.4 kHz. I suspect we will see other protocols emerge that squeeze the best data rate out of the 2.8 kHz bandwidth.

Living in a Narrowband World

The FCC proposal implements a 2.8 kHz bandwidth limit on data emissions on the HF bands. Some folks have suggested a narrower bandwidth while others argue that wider bandwidth signals should be allowed. And some even think we should have no bandwidth limit at all.

The problem is that the amateur HF bands are not very wide. For example, the popular 20m band is 14.0 to 14.350 MHz, providing only 350 kHz of spectrum. Common practice on this and the other HF bands is to use modulation types that have bandwidths of 3 kHz or less. (Yeah, AM signals are twice that wide, at 6 KHz, a topic for another day.) Of course, CW and some of the data modes are much narrower than 3 kHz. But the general approach to regulating HF is to allow many narrowband signals on the band. Limiting HF data transmissions to 2.8 kHz bandwidth is consistent with existing practice while still allowing for innovation and experimentation.

VHF/UHF Bandwidth Limits

The FCC also plans to issue a Further Notice of Proposed Rulemaking (FNPR) that:

  • Proposes to remove the baud rate limitation in the 2200 meter and 630 meter bands, which the Commission allocated for amateur radio use after it released the Notice of Proposed Rulemaking in 2016.
  • Proposes to remove the baud rate limitation in the VHF and UHF bands.
  • Seeks comment on the appropriate bandwidth limitation for the 2200 meter band, the 630 meter band, and the VHF/UHF bands.

I won’t comment on the 2200 meter and 630 meter bands. The FCC proposes to remove the symbol rate limit on the VHF and UHF bands and asks what bandwidth limit is appropriate. The current bandwidth limits are 20 kHz for the 6m and 2m bands, 100 kHz for the 1.25m and 70 cm bands, and the FCC seems fine leaving these the same. Authorized emission types are listed in FCC Part 97.305.

With 4 MHz of spectrum, the 2m band is much wider than any of the HF bands. It might be tempting to conclude that there is plenty of room for wideband signals on this band. Many hams think 2 meters is just used for FM simplex and repeaters but a closer look reveals that it supports many diverse modes: weak-signal SSB/CW, meteor scatter, EME, FM simplex, FM repeaters, digital voice modes (D-STAR, DMR, Fusion), satellites, and more. The 20-kHz limit seems appropriate, as it roughly matches the bandwidth of the most common (FM) voice signals on that band. It is not an appropriate band for trying out wider bandwidth signals.

The 6m band should probably keep the same 20-kHz limit. (I don’t think there is a compelling reason to change it.) The 1.25m band already allows 100-kHz bandwidth data signals, which some radio amateurs have used for higher-speed data links (still not what I would call wideband).

The 70 cm band is much bigger (420 MHz to 450 MHz) and could accommodate some wider bandwidth signals. Perhaps the existing 100-kHz limit should be increased? Keep in mind that fast-scan ATV is allowed on this band with a bandwidth of 6 MHz. Maybe we can make some room for a few larger bandwidth data channels, to encourage innovation and experimentation.

The bands above 70 cm have no bandwidth limit other than the signal must stay within the designated ham band. It has been this way for a long time, without causing any issues (that I know of).


The FCC’s proposal makes a lot of sense and it is long overdue. Frankly, it is a bit of an embarrassment that it has taken so long.

Better late than never.

73 Bob K0NR

The post Adios Symbol Rate Limit appeared first on The KØNR Radio Site.

Bob Witte, KØNR, is a regular contributor to and writes from Colorado, USA. Contact him at [email protected].


This is the most difficult article I’ve ever had to write, not only because I lost a very good friend, but also because it’s so hard for me to put into words and express the impact this person had on my life and others.

I met Rob about 25 years ago. Rob lived in Philly working long hours programming minicomputers. He developed various medical issues and had to retire early, relocating to the Poconos here in Pennsylvania. He tended to be a night owl, sleeping all day and relentlessly pursuing amateur radio projects at night. We served at our struggling local ham radio club for several years, me as president, him as vice president. He joked his callsign should be VP4LIFE. Rob was a ever-present friendly voice on the local 2 meter repeater, welcoming beginners and having conversations with other night owls well into the morning. We spent many a night at Field Day, operating the CW station and we both substantially improved our CW skills over the years.

Rob and I tended to be mentors to each other. We frequently had multi-week email conversations going about projects. Rob would get interested in a topic and he’d call or email me. Rob always seemed to know the right questions to ask. I would research the topic and inevitably get interested in it. We went down many technical rabbit holes over the years, some going nowhere, others resulting in some sort of rig, circuit, or antenna. I would often wake up in the morning to one or several 10,000+ word emails with pictures showing what Rob was experimenting with. Rob never bought a few components for a project, he’d buy 1,000 of each, and stockpile the unused parts in case he wanted to build more of something or give the parts away to others. Our last major conversation was about making vacuum tubes from scratch, with him collecting the necessary tooling and materials to do this. We complemented each other well, with Rob having the energy, curiosity, and ability to create the spark, and me with the technical know-how to figure things out and fan the spark to become a fire. I can honestly say I am a better radio amateur and person today because of Rob.

I’m still in shock over the loss of Rob. I often see some neat project and think that I should email Rob, but realize he’s no longer around. I open in my email in morning expecting to read a long diatribe about some late night experiments, but there is nothing there.

Robert Roomberg, KB3BYT, 63 years old, Silent Key. Dit dit.

This article was originally posted in Radio Artisan.

Anthony, K3NG, is a regular contributor to

Ham College 106

Ham College episode 106 is now available for download.

Extra Class Exam Questions – Part 44
E9B Antenna patterns and designs: E and H plane patterns, gain as a function of pattern,antenna modeling.


George Thomas, W5JDX, is co-host of AmateurLogic.TV, an original amateur radio video program hosted by George Thomas (W5JDX), Tommy Martin (N5ZNO), Peter Berrett (VK3PB), and Emile Diodene (KE5QKR). Contact him at [email protected].

Amateur Radio Weekly – Issue 304

Amateur Radio Weekly

New Elecraft KH1 Transceiver demo
Wayne Burdick N6KR Elecraft cofounder talking about the new KH1.

ISS SSTV Verification Test Oct 27-Nov 1
The SSTV system will be activated to attempt to verify a replacement piece of hardware.

Being a YL in Ham Radio
A personal experience.

40th anniversary celebration of the positive impact of Amateur Radio on human spaceflight
Held February 22-24, 2024, at the NASA Kennedy Space Center Visitor Center.

Eclipses do odd things to radio waves
An army of amateur broadcasters wants to find out why.

Linux Packeteering: The full service HF PBBS
How to set up your very own full service HF packet BBS on a Raspberry Pi.

Wind turbines for off grid radio: Pros and cons
Wind turbines, the forgotten stepchild of off grid power, deserves more attention.
Off Grid Ham

Listening to astronauts
All the elements screw together through the boom and so it makes it quick to put away and assemble.


K1N The Navassa Island DXpedition 2015
The complete video of the 2015 Navassa Island DXpedition.

USGS Shakeout exercise 2023 over Winlink: A video report
Participating in the USGS worldwide Winlink exercise.

Tape measure vertical on cheap dowel mast pulley system
Resonant on 5 bands.

Stealth foil antenna designed for a car sunroof
Simple antennas can bring joy and a sense of accomplishment.
Ham Radio Rookie

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Amateur Radio Weekly is curated by Cale Mooth K4HCK. Sign up free to receive ham radio's most relevant news, projects, technology and events by e-mail each week at

Hunting For NDBs In CLE279

Another month has zoomed by and it's CLE time once again. This is a challenge for all newcomers to NDB listening and the ultimate test of your medium frequency receiving capabilities. Can you meet the challenge?

'CLE's are 'Co-ordinated  Listening Events, and NDB DXers around the world focus their listening time on one small slice of  the NDB spectrum.
With the number of targets slowly being decommissioned, the hunting grounds have been slightly widened ... this month the frequency range is for the NDBs whose published frequencies are between 335.0 - 349.9 kHz

When tuning for NDBs, put your receiver in the CW mode and listen for the NDB's CW identifier, repeated every few seconds. Listen for U.S. NDB identifiers approximately 1 kHz higher or lower than the published transmitted frequency since these beacons are modulated with a 1020 Hz tone approximately.

For example, 'AA' near Fargo, ND, transmitted on 365 kHz and its upper sideband CW identifier was tuned at 366.025 kHz while its lower sideband CW ident could be tuned at 363.946 kHz. Its USB tone was actually 1025 Hz while its LSB tone was 1054 Hz.

Often, one sideband will be much stronger than the other so if you don't hear the first one, try listening on the other sideband.

Canadian NDBs normally have an USB tone only, usually very close to 400 Hz. They also have a long dash (keydown) following the CW identifier.

All NDBs heard in North America will be listed in the RNA database (updated daily) while those heard in Europe may be found in the REU database. Beacons heard outside of these regions will be found in the RWW database.

From CLE organizers comes the following info:

Hello all

Here are the full details for this weekend's co-ordinated listening event.
It is open to everyone including CLE new-comers:

    Days:       Friday 27 Oct. - Monday 30 Oct.

    Times:     Start and end at midday, LOCAL time at the receiver.

          NB:   Most of us are changing our clocks by one hour this weekend.

                   However UTC time (as shown in our logs) continues unaffected.   

    Range:     335.0 - 349.9 kHz

Wherever you are, please join us and log the NDBs that you can positively
identify that are listed in this busy frequency range (it includes 335.0 kHz
but not 350 kHz), plus any UNIDs that you come across there.

Short and long logs are welcome (in-between ones are good too!)

    Send your CLE log to the List, preferably as a plain text email
    (not in an attachment) with ‘CLE297 FINAL’ in its subject line.

    Please show on EVERY LINE of your log:
       #  The date (e.g. '2023-10-27' or just the day no. '27') and UTC
           (the day changes at 00:00 UTC).
       #  kHz  (
The beacon's nominal published frequency)

              If you don’t know it, please visit

              where you will find all the details.
       #  The Call Ident.

Show those main items FIRST on each line, before other optional 
details such as Location, Distance, etc.  If you send any interim logs during the event, please also send your 'FINAL', complete, log.

Always make your log interesting to everyone by giving details of your listening location (the 6-character Locator) and brief details of the receiver, aerial(s), etc., that you were using.

We will send the usual 'Any More Logs?' email at about 19:00 UTC
on Tuesday so that you can check that your log has been found OK.
Do make sure that your log has arrived on the List at the very latest
by 08:00 UTC on Wednesday 1 November.  We will then hope to 
complete making the combined results within a day or two.

You can find full information about current and past CLEs from the

CLE page

You can also find your relevant seeklists made from REU/RNA/RWW by visiting

Good listening


   Brian and Joachim

   (CLE Coordinators)

(Reminder:  You could use any ONE remote receiver for your loggings, stating its location and owner - with their permission if required. A remote listener may NOT also use another receiver, whether local or remote, to obtain further loggings for the same CLE)


CLE's provide several purposes. They:

• determine, worldwide, which beacons are actually in service and on-the-air so the newly-re-vamped Rxx online database can be kept up-to-date

• determine, worldwide, which beacons are out-of-service or have gone silent since the last CLE covering this range

• will indicate the state of propagation conditions at the various participant locations

• will give you an indication of how well your LF/MF receiving system is working

• give participants a fun yet challenging activity to keep their listening skills honed

Final details can be found at the NDB List website, and worldwide results, for every participant, will be posted there a few days after the event.

The NDB List Group is a great place to learn more about the 'Art of NDB DXing' or to meet other DXers in your region. There is a lot of good information available there and new members are always very welcome. As well, you can follow the results of other CLE participants from night to night as propagation is always an active topic of discussion.

You need not be an NDB List member to participate in the CLEs and all reports, no matter how small, are of much value to the organizers.

Remember - 'First-time' logs are always VERY welcome!

Reports may be sent to the NDB List Group or e-mailed to CLE co-ordinator, Brian Keyte (G3SIA), whose address appears above. If you are a member of the group, all final results will also be e-mailed and posted there.

Please ... give the CLE a try ... then let us know what NDB's can be heard from your location! Your report can then be added to the worldwide database to help keep it up-to-date.

Have fun and good hunting!

Steve McDonald, VE7SL, is a regular contributor to and writes from British Columbia, Canada. Contact him at [email protected].

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