Zero Retries 0258
2026-07-24 - ZRDC 2026 Registration Now Open, Zero Retries Digital Conference (ZRDC) 2026 Call For Papers is Now Open, What’s New at DLARC — July 2026, What’s New with New Packet Radio Next Generation
Zero Retries is an independent newsletter promoting technological innovation in and adjacent to Amateur Radio, and Amateur Radio as (literally) a license to experiment with and learn about radio technology. Radios are computers - with antennas! Now in its sixth year of publication, with 3500+ subscribers.
Steve Stroh N8GNJ, Editor
Tina Stroh KD7WSF, Business / Conference Manager
Substack says this issue is likely to be truncated by some email clients. Thus, it might be easier to read in a web browser - www.zeroretries.org/p/zero-retries-0258.
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In This Issue:
ZRDC 2026 Registration Now Open
Tina Stroh KD7WSF
Zero Retries Digital Conference (ZRDC) 2026 Call For Papers is Now Open
Donald Rotolo N2IRZ
What’s New at Digital Library of Amateur Radio & Communications — July 2026
Kay Savetz K6KJN
What’s New with New Packet Radio, Next Generation (NPR-NG)?
Steve Stroh N8GNJ
Fixing the US Amateur Radio Licenses
Steve Stroh N8GNJ
I-Frame
By Steve Stroh N8GNJ
Brief notes about this issue of Zero Retries.
Paid Subscribers / Founding Members Update
My thanks to Eric Stammers M0REQ for renewing as an Annual Paid Subscriber (3rd year!) to Zero Retries these past two weeks!
My thanks to Rick Gilmore W3TM for renewing as an Annual Paid Subscriber (3rd year!) to Zero Retries these past two weeks!
My thanks to Scott Honaker N7SS for renewing as an Annual Paid Subscriber (3rd year!) to Zero Retries these past two weeks!
My thanks to Chuck Till K4RGN for renewing as an Annual Paid Subscriber to Zero Retries these past two weeks!
My thanks to Stuart Whiting WS7SW for renewing as an Annual Paid Subscriber to Zero Retries these past two weeks!
Financial support from Zero Retries readers is a significant vote of support for the continued publication of Zero Retries.
Zero Retries Summer 2026 Publishing Schedule - Biweekly
During Summer 2026, Zero Retries will be published biweekly. The intended publication schedule for the remainder of Summer 2026 is:
Zero Retries 0258 - 2026-07-24
Zero Retries 0259 - 2026-08-07
Zero Retries 0260 - 2026-08-21
Zero Retries 0261 - 2026-09-04
There may be some special, focused issues interspersed between the scheduled issues, such as a special issue about Zero Retries Digital Conference (ZRDC) 2026.
After ZR 0261 / 2026-09-04… to be determined.
Please direct comments / feedback about I-Frame to the Zero Retries email list with the hashtag #ZR0258. Paid subscribers can comment directly on the web version of this issue.
ZRDC 2026 Registration Now Open
By Tina Stroh KD7WSF
Zero Retries Digital Conference Manager
Click here to register for ZRDC 2026
We are excited to announce the registration for our second Zero Retries Digital Conference (ZRDC 2026) is now open! This year’s conference will bring together Hams and people interested in the technological innovations in Amateur Radio to explore and listen to expert speakers, regarding various topics pertinent to digital communications. Attendees will have the opportunity to participate in engaging sessions, and connect with colleagues from across the industry. In the next few weeks, we will be compiling our list of speakers and will update that list in Zero Retries weekly until the roster is complete.
Registration will again offer in-person access and virtual attendance options to attend the conference. Ticket price descriptions state what is included with each level of participation. Such as, in-person attendance includes access to the conference along with conference proceedings, welcome refreshments, and a chance to win raffle prizes. Throughout the day, coffee service, lemonade and fruit infused water will be available. There are several food options for purchase at the conference center.
Whether you’re looking to gain new insights, share ideas, or expand your professional network, this conference offers valuable opportunities for everyone. We encourage you to reserve your spot early.
We look forward to welcoming you to another successful year of learning, collaboration, and innovation!
ZRDC 2026 will be held on Friday, October 16th, 2026 at the Roundhouse Conference Center in San Ramon, California. This venue is on the back side of the San Ramon Marriott Hotel where the 2026 Pacificon Conference will the held the same weekend. Pacificon will be held Friday, October 16 through Sunday, October 18th and is one of the largest conferences on the West Coast. Friday, October 16th is the only day the conferences will overlap.
While ZRDC 2026 and Pacificon 2026 are being held the same weekend and in very close proximity, they are two separate events. Please see the links to each event and consider attending both events.
The most current information about ZRDC 2026 can be found at www.zeroretries.org/p/conference (or the Conference link on the top bar of the Zero Retries page).
Please share this information about ZRDC 2026 to your friends that are interested in Zero Retries Interesting subjects.
Please direct comments / feedback about this article to the Zero Retries email list with the hashtag #ZR0258. Paid subscribers can comment directly on the web version of this issue.
Zero Retries Digital Conference (ZRDC) 2026 Call For Papers is Now Open
By Donald Rotolo N2IRZ
Technical papers are sought for the Proceedings of the (second annual) Zero Retries Digital Conference (ZRDC) 2026, to be held at the Roundhouse Conference Center in San Ramon, California, USA on Friday, October 16, 2026. This coincides with the first day of Pacificon 2026.
ZRDC 2026 is being hosted by the Zero Retries newsletter. Papers will be published in the Conference Proceedings of the ZRDC. Authors do not need to present at the conference to have their papers included in the Proceedings, although presenters are highly encouraged to submit a separate technical paper (for the Proceedings). All presenter presentations will also be published in the Proceedings.
A typical technical paper for ZRDC is a short (typically 5-10 pages) but in-depth explanation of a project, experiment, or new technique. A technical paper typically includes the problem(s) to be solved and how the solution was built and tested, and what was learned. Diagrams, data, and code are often included. The intended audience for technical papers are not just the attendees of a particular ZRDC - they’re intended to help others implement or enhance the subject of the technical paper.
A ZRDC technical paper is different from a presentation slide deck:
A technical paper is self-contained - all of the needed detail is in the text of the technical paper. A presentation slide deck provides speaking points - the detail is in the presentation narration.
A technical paper explains the idea in depth for the long term. A presentation slide deck is a “snapshot” of an idea at that moment in time.
Very generally, a technical paper explains the details of how you did something. A presentation slide deck explains (generally) what you did to expose the idea to those who aren’t familiar.
ZRDC 2026 Paper Submission Details
Paper submission deadline is Monday, September 28, 2026 23:59 UTC. Submissions received after this date will not appear in the Proceedings.
Submit papers via email to zrdcpapers@zeroretries.net
Papers must be submitted as a .PDF format, with sufficient resolution for print publication. (Export or Save As… PDF).
It is requested that ZRDC papers not use inline web hyperlinks. (Hyperlinks often do not persist through format changes.) In lieu of inline web hyperlinks, simply type out the full URL of the link. For longer URLs, please use footnotes with the full URL in the footnote.
Papers will be published exactly as submitted.
Paper authors retain all rights.
Papers with multiple authors are encouraged.
Papers are limited to 12 pages (letter-size).
In addition to ZRDC archives, ZRDC technical papers will be archived for posterity in the Digital Library of Amateur Radio & Communications (DLARC), a project of the Internet Archive.
Technical paper topic areas include, but are not limited to digital radio, radio networking, mesh networks over radio, Software Defined Radio (SDR), digital voice/data systems, digital satellite communication, use of LoRa in Amateur Radio, digital signal processing (DSP), HF digital modes, Spectrum Management, Global Positioning System (GPS), Automatic Packet Reporting System (APRS), Linux in Amateur Radio, AX.25 and other protocols, mesh and peer-to-peer wireless networking, emergency and homeland defense backup digital communications in Amateur Radio.
Please share this info to your “Zero Retries” folks that are working on relevant projects, products, and technologies, software, etc. If you have a favorite vendor that is doing Zero Retries Interesting things, perhaps encourage them to submit a paper. A PDF version is included below for easy sharing.
If you’d like to include this announcement in a newsletter, news release, etc., an .RTF and a .TXT version (for easier copy and paste) is available on the ZRDC page.
The latest information on ZRDC 2026 will be maintained at www.zeroretries.org/p/conference, or just click the Conference link on the top bar of the Zero Retries web page (https://www.zeroretries.org/).
Please direct comments / feedback about this article to the Zero Retries email list with the hashtag #ZR0258. Paid subscribers can comment directly on the web version of this issue.
What’s New at Digital Library of Amateur Radio & Communications — July 2026
By Kay Savetz K6KJN
Greetings from DLARC World Headquarters, where it’s 99 degrees and there’s a heat advisory: perfect weather for staying inside to play with computers and radios. But — oh no, when you’re cozy and cool indoors, you can’t look up to see the satellites.
DLARC has significantly expanded the AMSAT Symposium archive, adding about 250 new items from AMSAT Space Symposium events. Newly archived material includes audio recordings of the 2007-2008 presentations, matching slide decks, photo albums, and video clips, from 2013-2020, AMSAT-NA proceedings for 2013-2019, and a full set of 2025 symposium papers, slides, and videos.
Especially valuable are the 2007 and 2008 symposium materials, which preserve the talks as they were distributed on AMSAT’s conference DVDs: audio recordings, slide decks, photos, video clips, and schedules. These include presentations on AO-51, ARISS, Eagle, SuitSat-2, digital signal processing, satellite telemetry, CubeSat education, and the state of amateur satellite engineering in the late 2000s.
Bonus: we’ve added the contents of a 2002 ARISS CD-ROM, produced when ARISS was operating under AMSAT, with presentations, ISS and equipment photos, QSL card images, and video of antenna installation and school-contact activity.
Big news: the Manuals Plus project is done. Like, done done, put a bow on it. This massive manual scanning project started more than a decade ago, in 2015 when a company called Manuals Plus went out of business and donated pallets of rare manuals to Internet Archive. Then, a couple of years ago, DLARC scanned four pallets of the radio-related manuals. In September 2025, I announced in this space that we were back for another bite of the apple, with nine more pallets of tech manuals going to the scanning center. There was no way to know ahead of time what products the manuals were for: some would be for radio-related equipment, some wouldn’t. Internet Archive scanned it all, then we separated out the material relevant for DLARC. More than 10,600 manuals were deemed “DLARC-worthy” out of a total collection of 13,046 manuals. You’ll find manuals for rare amplifiers, radios, and all sorts of tools and test equipment. My colleague Jason Scott wrote a blog post titled Manuals Plus: The Wrap-Up that nicely summarizes the whole adventure.
More big news: the DLARC Software collection is expanding! I’ve been on a source code scavenger hunt, finding and archiving historical releases of important amateur-radio software projects. I’ve concentrated on self-contained release tarballs and ZIP files—the source packages people could actually download and build at the time. Some were waiting patiently on old FTP servers. Others were scattered among SourceForge, Debian Snapshot, the Wayback Machine, dusty mirrors, and personal archives.
The heavyweight is the W1HKJ/fldigi family: 184 source archives covering 17 related digital-mode, messaging, file-transfer, logging, and rig-control programs. The collection follows fldigi back to version 1.30 in 2007, filling the early years with tarballs preserved by Debian and continuing through the surviving W1HKJ and SourceForge archives. And there’s Xastir, the APRS mapping and communication program, which uncovered more than 160 source packages beginning in 2002. The early developers released snapshots at a furious pace (sometimes several in a month), so the collection preserves major milestones and also small steps in the program’s evolution.
WSJT and WSJT-X, Joe Taylor K1JT’s family of programs for extremely weak-signal communication, including meteor scatter, Earth-Moon-Earth, and FT8, are represented by 53 source archives, tracing the software from its beginnings in 2005 through present-day WSJT-X.
I’ve also archived source code for Gpredict, a satellite-tracking and orbit-prediction program; Hamlib, the common rig- and rotator-control library used by scores of ham-radio applications; PREDICT, the veteran satellite-tracking and antenna-control program; LinFBB, a packet-radio BBS and message-forwarding system; Thomas Sailer’s Soundmodem, which turns a computer sound card into a packet-radio modem; and the unixcw and cwdaemon Morse-code tools.
Each item includes a chronology, source URLs, and notes explaining gaps, duplicate versions, historical mirrors, and anything DLARC had to reconstruct from an official source tree. I’ll continue these source code scavenger hunts to grow the software collection in the coming months.
On to newsletters! We’ve scanned 40 issues of Cornell-Dubilier Capacitor, which was a technical/service newsletter for the radio and TV repair trade. Cornell-Dubilier, a capacitor manufacturer, began in 1933 when two companies, Dubilier and Cornell Radio, merged. The Capacitor was published from 1937 through 1964.
More club recent reading fare: 146 issues of K9YA Telegraph, the publication of the Robert F. Heytow Memorial Radio Club, based in Skokie, Illinois. The newsletter, spanning 2004-2018, emphasizes Morse code, CW operating, and radio history. And, 142 issues of the Sierra Nevada Amateur Radio Society “Cracklin’ Static” Newsletter. And also, Skywaves, the newsletter of the Sachse Amateur Radio Association, a ham club in Sachse, Texas. We’ve also added 40 issues of QTC Magazine, the publication of the Radio Amateur Society of Australia, from 2020 to the present.
Finally, DLARC has also adopted the SatNOGS collection: observation audio data from SatNOGS, the Distributed Network of Satellite Ground Stations. SatNOGS ground stations observe and receive satellite signals, particularly low-Earth-orbit CubeSats. Initially, SatNOGS focused on retrieving signals from LEO satellites in UHF and VHF bands. Now, SatNOGS is able to retrieve status and telemetry signals, data transmitted by experiments from scientific and research satellites, weather data, and more. The group has been uploading daily observation data since 2021, and now that data has a home in DLARC. More information about the project is at satnogs.org.
Digital Library of Amateur Radio & Communications is funded by a generous grant from Amateur Radio Digital Communications (ARDC) to create a free digital library for the radio community, researchers, educators, and students. If you have questions about the project or material to contribute, contact me at kay@archive.org.
Please direct comments / feedback about this article to the Zero Retries email list with the hashtag #ZR0258. Paid subscribers can comment directly on the web version of this issue.
What’s New with New Packet Radio, Next Generation (NPR-NG)?
By Steve Stroh N8GNJ
Because this is a YouTube “Short”, I’m unable to include it in the Zero Retries YouTube channel playlists, and a lot of the usual amenities of YouTube, such as Substack’s embed a YouTube video feature, aren’t available. Unless you’re a follower of ARDC on YouTube (www.youtube.com/@ardc73) or the algorithm presents it to you (as it did me), you’re likely to miss this video.
This news is easily the fourth1 most Zero Retries Interesting development of 2026 (to date). The title link is to a YouTube video Short posted by ARDC (Thank You, whoever did that interview) is the first inkling I’ve seen about “New Packet Radio - Next Generation”. This interview at HAM RADIO 2026 is with Steffen Heuel DO5DSH of Localino about NPR 3.0 (briefly) and then launches into a discussion of NPR-NG.
I like to think I’m “on top of things” with all things data communications in Amateur Radio… but clearly, I’m not because I had no hint of this, and saw no other mentions of this development other than this video.
NPR-NG is a follow-on to NPR 3.0, which is now available as an assembled and tested series of radios from Localino for 2m, 70cm, and 23cm. Here are the impressive features of NPR-NG as explained by DO5DSH:
Will operate on 70cm,
Uses OFDM,
Modulation index is 64 QAM,
Minimum bandwidth is 1 MHz,
Data rate is 3.2 Mbps,
Operating system is OpenWRT
Form factor is a Raspberry Pi HAT
Although NPR-NG is not yet a product, Localino has a great track record with their improved versions of the original NPR, and creating the NPR 3.0 products. The prototype shown has a separate Receive input and Transmit output. D05DSH says future work to be done is:
Combiner added for a single Receive and Transmit connector,
Add a linear amplifier for higher transmit power,
Firmware improvements.
One interesting aspect of NPR-NG is that there was no mention of backwards compatibility with NPR / NPR 3.0. Thus it seems likely that NPR-NG will be a completely new version of (fork?) of NPR.
Another interesting aspect of NPR-NG is that it will be based on OpenWRT. That’s very interesting from the networking perspective because the mature and proven AREDN networking software is also based on OpenWRT. Thus instead of the limited number of nodes that could interoperate in “classic” NPR and NPR 3.0, potentially AREDN networking could make use of 420 - 450 MHz / 70 cm using its robust capabilities to manage many nodes in a network. At 3.2 Mbps, AREDN’s implementation of Babel mesh networking at the beginning of 2026 should operate well with a (potential) “AREDN NPR-NG”.
But… a bummer aspect about NPR-NG for US VHF / UHF data communications experimenters / network builders is that NPR-NG is a complete non-starter for US Amateur Radio Operators. Current US Part 97 Amateur Radio regulations limit the maximum bandwidth of data communications on the US 420-450 / 70 cm band to 100 kHz. Absent such an update of the US Amateur Radio regulations, the only possibility for use of NPR-NG would be an FCC Special Temporary Authority or a Part 5 Experimental License. Applying for those isn’t really feasible until NPR-NG is actually a product that US Amateur Radio Operators could buy… but not be allowed to use in the US.
Postscript
After I finished this article, I reached out to D05DSH and I hope to have some followup from him in a future issue of Zero Retries.
Please direct comments / feedback about this article to the Zero Retries email list with the hashtag #ZR0258. Paid subscribers can comment directly on the web version of this issue.
Fixing the US Amateur Radio Licenses
By Steve Stroh N8GNJ
I’m a fan (and former colleague doing volunteer work for ARDC) of Bob Witte K0NR. KONR is thoughtful and articulate, and I follow his postings on his blog K0NR Above Average Terrain. K0NR is one of the Directors of ARDC, thus he has a bit more “pull” in Amateur Radio than most of us, thus even more reason to pay attention to what he’s thinking and writing.
I don’t know how I missed this good article K0NR wrote in 2025, but I only recently saw it - The Case of The Shrinking Technicians. It’s a reasonably qualified (he explains the methodology) dive into actual numbers of US Amateur Radio licensees. When there’s some reasonable methodology being applied, despite the apparent rise in overall number of licensees, K0NR argues that the overall number of licensees is declining.
That article, at least in my mind, feeds into his most recent thinking about the US Amateur Radio Technician License - How to Fix the Technician License.
Basically… (apologies for oversimplification), K0NR proposes tinkering a bit about the privileges of the Technician class license to “get a taste” of HF operation.
I disagree.
What I’m seeing in the readership of Zero Retries and the NewTechHams that I’m continually encountering is that their interest is mostly in VHF / UHF operation… not HF.
When I’ve discussed HF with NewTechHams that I meet, and mention that they can do interesting things on HF if they “upgrade” to a General class license, the typical response is a variation that I’m talking about a “bait and switch” maneuver. They were encouraged to “get their Amateur Radio license”. And they did! And now, they’re being told, in effect, “well… you didn’t get the good Amateur Radio license”.
With such proposals as “more incentivized licensing” and the reforms that K0NR advocates, what my generation of Amateur Radio Operators just doesn’t seem to get is that there is not a generational “divide” between them and NewTechHams…
There’s a generational chasm. And it’s all about digital / data operation.
A Technician class licensee “venturing into HF” with the ability to operate only CW or a few tiny slivers of HF (such as 10 meters) with voice… is not an “incentive” in 2026. It’s the opposite - it’s a disincentive.
If Amateur Radio writ large wants to increase the number of Amateur Radio Operators operating on the HF bands… then just make it feasible for Technicians to use the HF bands. The current incentive license structure, to this generation, smacks of gamesmanship / hoop jumping / jerking them around, and simply, they have no patience for such things. NewTechHams want to dive in and get on with it. To them, Amateur Radio isn’t a long-term commitment or a lifestyle. It’s an activity that is either quickly engaging and satisfying, or it isn’t.
That Amateur Radio doesn’t prove to be engaging and satisfying because if you’re not a NewTechHam, just an average person who was encouraged to get an Amateur Radio license “to be prepared for emergencies”, you learn enough, pass the test, get the license, buy the portable, try to use it and are generally disappointed (quiet repeaters, poor performance of a portable indoors when accessing a repeater, etc.). The verdict of Amateur Radio from that experience - Meh. I think that experience chain is the primary reason for the decline of Techs licensees discussed in the first K0NR article.
NewTechHams are proving willing to give Amateur Radio a try. They’re getting licensed. As evidenced in the pages of Zero Retries, they’re doing lots of interesting technical experimentation and operation (building networks, developing Software Defined Radio, etc.)
To me, the really damning aspect of this “divide” is that HF can indeed be a lot of fun, especially now that we have engaging new generations of HF radios. My former “most fun HF radio” was the HF Signals zBitx. That had some first generational problems, but those seem to be ironed out with zBitx v2. But the now favorite “most fun HF radio” is the Pebble HF, with the price goal of $50.
Darn if that thing is cute! From my reading, t’s developed a good reputation and that seems to be borne out by it being currently unobtanium. If you weren’t in on the crowdfunding campaign (as I wasn’t), apparently we’re in for a long wait. But I’m willing to do that because I want to play with one and take it with me and do some HF operating (digital modes, of course) outdoors away from home.
But again, the damning thing is that the Technician class licensees (that, again, in good faith, jumped through the hoops and got their Amateur Radio license…) only to be told that they can’t do the cool stuff like use a Pebble HF on the 20m HF band.
And that leaves a sour taste. Bait and switch. Hoop jumping.
And for what?!?!?! Answering a few more questions that are mildly more technical on to “qualify” you for a General license?
Here’s my proposal to “fix” Amateur Radio licensing. It’s so laughably simple it couldn’t possible get past the powers that be in Amateur Radio to get passed along to the FCC (which, I believe would say “Fine… whatever.”):
Combine the US Amateur Radio Technician and General Licenses into a single license.
Call it the Standard license (to differentiate it from the Extra license, which is unchanged).
Don’t take away any of the capabilities of the General license.
Promote all current Amateur Radio Technician licensees into the same privileges as General licensees.
Make the test a bit more challenging with a bit more technical knowledge required - mostly digital technology / SDR which is more relevant than arcane radio circuits or formulas that aren’t necessary to operate with current off-the-shelf equipment.
In summary, if we in US Amateur Radio really want to “fix” Amateur Radio and get more activity from younger folks and newer Amateur Radio Operators… and make Amateur Radio interesting enough to retain them… then we have to stop tinkering / dinking around at the margins and make an Amateur Radio license appear relevant to the current generation.
And… um… we need to finish fixing VHF / UHF bands by removing the symbol rate limitations and maximum bandwidth limitations.
And… we really need to make some changes to accommodate encryption in some commonsense meaningful way like Amateur Radio in Canada has done. Every time you see an https:// in a web browser page that has transited an Amateur Radio link, that’s encryption (and it happens all the time).
For another perspective on this issue, Jeff Davis KE9V has (as usual) a unique perspective, eloquently expressed: FT8 Is a Fad, and Other Heresies.
My thanks, again, to K0NR for some great food for thought.
Please direct comments / feedback about this article to the Zero Retries email list with the hashtag #ZR0258. Paid subscribers can comment directly on the web version of this issue.
ZR > BEACON
By Steve Stroh N8GNJ
Short mentions of Zero Retries Interesting items.
MODEM 73
From the web page:
MODEM73 is an open source software modem that works with any HF, VHF, or UHF radio capable of 2400 Hz of bandwidth.
From the GitHub page:
MODEM73 is an open source software modem that works with any HF, VHF, or UHF radio capable of 2400 Hz of bandwidth. All you need is a sound card and audio cable for your radio.
SSB, AM, and FM are all supported. It’s plug and play compatible with any KISS application and works with rigctl, CM108 sound devices, and serial PTT out of the box.
There are three modem families each suited for covering any possible RF setup from clean line of sight FM links to poor HF band conditions. The receiver decodes all of them at the same time, so one station can hear anything another station sends without switching modes.
OFDM, based on the open source COFDMTV modem developed by Ahmet Inan / aicodix GmbH. Modulations from BPSK to QAM4096 with code rates from 1/4 to 5/6 and payloads from 256 to 6144 bytes per frame. Rates run from about 790 bits per second to over 13 kilobits per second in the same 2400 Hz.
ROBUST, a set of slow modes built for fading HF paths such as 40 and 80 meter NVIS. Five modes from 1150 bps down to 149 bps in either 2400 Hz or a 600 Hz narrow variant
MFSK, a non-coherent mode for weak signal propagation and backup links.
Features
KISS over TCP so it works with anything that speaks KISS: APRS clients, HamIRC, packet BBS software, Reticulum, custom applications
JSON control port API for status and configuration for writing your own programs
lightweight UI that runs straight from the terminal and headless mode for embedded use
…
Want to try out a demo of modem73 directly from your browser? Try it out here: https://rfnexus.github.io/modem73-wasm-demo/ Hit “Start microphone” to begin decoding.
I was alerted to MODEM 73 by Georges Auberger WH6AZ who commented:
Looks very promising. The design seems very clean to expose the modem as a service layer. While it does not handle adaptive rate itself, it should allow the app to do it on its own.
I agree. We just keep getting better and better options for digital communications in Amateur Radio as the “software folks” apply better software / signal processing technology on the increasingly capable computer hardware we have access to… like Raspberry Pi 5 and the current generation of mobile phones (aka pocket supercomputers).
Mercury v1.9.10 Released
Pedro Messetti on the hermes-general email list:
We are happy to announce Mercury v1.9.10.
Highlights:
New graphical UI
- Brand-new cross-platform GUI ("Mercury Modem", Fyne-based) embedding
the modem engine (no separate processes needed)
- Self-contained universal macOS .app/.dmg (Intel + Apple Silicon)
- New mercury-ui Debian package
- Windows installer (Mercury_1.9.10_Setup.exe) available for all Windows
users
Modem and ARQ:
- New robust modes: DATAC15/DATAC16, plus DATAC17 and QAM16C2, extending
the adaptive ladder to 6 levels (DATA payload up to 2047 bytes)
- Outer-loop link adaptation (OLLA): SNR + delivery-feedback
gear-shifting, tuned for asymmetric links
- HARQ Chase soft-combining on data modes
- Channel-busy detector with VARA-compatible BUSY ON/OFF reporting
- ARQ timing constants now tunable via mercury.ini
- Many robustness fixes: turn-coordination and TX-ring deadlocks,
fade-cliff stall, last-frame loss on disconnect, ACCEPTING linger
Compatibility and Audio:
- Hamlib 5.0.0 compatibility
- Polyphase FIR resampler (fixes TX clicks), support for
16-bit/mono-only sound cards, ALSA capture wedge recovery
Download Windows installer (still not signed but we are working on it):
https://github.com/Rhizomatica/mercury/releases/download/v1.9.10/Mercury_1.9.10_Setup.exe
Windows binary and Debian packages available.
MacOS release is coming soon.
Full changelog:
https://github.com/Rhizomatica/mercury/compare/v1.9.9...v1.9.10
Thanks to everyone who contributed, tested and reported issues.
Please support the ongoing development of Mercury HF modem:
<https://www.paypal.com/donate/?hosted_button_id=EKY4LRAH64Z9S>
The general release of Mercury is one of the most Zero Retries Exciting developments of technological innovation in Amateur Radio in 2026. The GUI and additional modes are especially exciting in this release.
RadioMail 1.6 - The “Freedom HF modem” Release
I’m happy to announce that RadioMail 1.6 is now available on the App Store.
This release focuses on bug fixes and quality-of-life improvements. One of the biggest usability improvements is bulk message editing. You can now select multiple messages, or select all, to move or delete in one step.
There’s also experimental emoji support. Winlink is limited to the ISO-8859-1 character set, so emojis can’t be transmitted directly. They do display correctly between RadioMail users though. Not exactly standards compliant, but good enough to have a little fun 🤪. Who knows, maybe other Winlink clients will adopt it too. Here’s the supported emoji mapping.
The biggest addition is a built-in ARDOP modem for HF. Supported sound card interfaces include:
Digirig Lite
AIOC (All-In-One Cable)
ICOM IC-705 (USB audio with Bluetooth CAT control)
This is the first HF software modem integrated directly into RadioMail. Along with packet, there are now two open standards for connecting and exchanging email over radio. I’m committed to adding more open modes over time so we can eliminate unnecessary dependencies on external hardware.
This release also includes significant internal refactoring to address changes introduced in the upcoming iOS/iPadOS 27 that were causing crashes. Hopefully there won’t be any further breaking changes before iOS 27 is released later this year.
If you plan to upgrade to iOS 27, you’ll need RadioMail 1.6.
Update on RadioMail 2.0
RadioMail 2.0 will be released as a new app rather than an update to the 1.x series.
The scope of the changes made this the right time for a clean break from the original codebase, provides a stronger foundation for future development. It also gives me the freedom to simplify the user experience by retiring features without taking anything away from existing users.
When RadioMail 2.0 is released later this year, RadioMail 1.x will enter maintenance mode. It will continue to work, but will no longer receive new features or updates.
Existing users who choose to upgrade will be able to perform a one-time migration of their email archive.
If you’ve purchased RadioMail recently, you’ll receive an extended trial period to explore RadioMail 2.0 and decide whether it’s the right upgrade for you. I’ll share more details about migration and upgrade options closer to launch.
B.B. Link sunset
The B.B. Link adapter is now officially sold out.
Thanks to everyone who picked one up and helped clear the final production run. I’m especially grateful not to have a stack of leftover PCBs taking over the linen closet. My wife thanks you too.
Georges Auberger WH6AZ has created a number of delightful Amateur Radio data communications apps for the iOS ecosystem (iPhones, iPads). Be sure to read the section A Passion Project. I hope that he will do extend the ecosystem to MacOS. I’m looking forward to… one of these days… to a clean user experience with my MacBook laptop easily connecting, either via USB or Bluetooth to a mobile radio with good data communications capabilities (reasonable power, reasonable data communications speed).
The same observation I made about in the story about MODEM73 applies to apps like those offered by WH6AZ (running on pocket supercomputers and their larger tablet cousins):
We just keep getting better and better options for digital communications in Amateur Radio as the “software folks” apply better software / signal processing technology on the increasingly capable computer hardware we have access to… like Raspberry Pi 5 and the current generation of mobile phones (aka pocket supercomputers).
AREDN Release 4.26.7.0 Available
The AREDN team is proud to announce AREDN production release 4.26.7.0. Features and fixes are listed below. For the gory details, go to the ChangeLog:
Enjoy!
The AREDN Dev Team.Major Features
Updated to OpenWRT 25.12.5
OpenWRT 25.12 brings a new package manager - apk. If you are currently using side-loaded .ipk packages, these cannot be updated when AREDN is updated as they are no longer compatible and will be removed.
Faster network changes
You can now add, remove, or update tunnels without restarting the entire network stack. It’s a lot faster and less disruptive.
Improved HaLow 802.11ah support
Updated to the latest Morse Micro 1.17.9 drivers which improves stability and performance of HaLow links.
Support for MediaTek WiFi-6 AX devices
Improved support for AX radio based devices. Note that these radios come with a number of limitations, including only supporting 20 MHz or greater bandwidth.
Zyxel radios
Zyxel is a new manufacturer to AREDN. We support the NWA55AXE. It is the only outdoor rated AX radio supported by OpenWRT, and has connectorized antennas so can be attached to your antenna of choice.
Supernode Babel improvements
Improve the babel configuration for Supernodes. Supernodes handle a lot of routes and these changes get better Babel performance especially on non-x86 hardware.
New Devices Supported
Morse Micro HalowLink 2
Heltec HT-HD01 V2
Heltec HT-H7608 V2
Ubiquiti PowerBeam 5AC 300
GL.iNet Slate Plus (GL-A1300)
Cudy WR3000
Cudy WR3000E
Cudy WR3000H
Cudy WR3000P
Cudy WR3000S
Zyxel NWA55AXE
Vultr Cloud Compute
It is continually amazing that AREDN just keeps getting improved. Look at the umpteen Fixes and Enhancements that have been incorporated!
Kudos to the AREDN Development Team (and AREDN Ambassador Orv Beach W6BI who does such a good job evangelizing and publicizing AREDN.
EastNet Packet Radio Group Quarterly Call Summary
Brian Webster N2KGC on the EastNetPacket email list:
We had a good call this morning with 10 participants. We used the Google Chat video conference system and I had the Gemini AI take notes. I have read through the note and other than a few errors with things like call signs and it calling the TPRFN the Tri-State Packet network, it did a real nice job. The summary is an easy read and it captured all of the topics we covered very well. It time stamps those points in the meeting so you can go to the full transcript for the actual details.
The summary link is here: https://docs.google.com/document/d/1dDso_mep1abFLgKUivzdPYrIMvtD9ohd6_KrTKs5Hms/edit?tab=t.m9uyqifyusei
The full transcript document is here: https://docs.google.com/document/d/1dDso_mep1abFLgKUivzdPYrIMvtD9ohd6_KrTKs5Hms/edit?tab=t.4bqirv4y43n0
Th meeting was held 2026/06/13 08:58 EDT, with Notes by Gemini.
Summary
Technical experts reviewed network integration strategies and protocol efficiency updates for packet radio communication systems.
Network Integration And Configuration
Discussions focused on integrating digital traffic networks with packet radio frequency systems to streamline messaging. The group decided to prioritize configuring BBS software to ensure proper traffic routing and system performance.
Protocol Efficiency And Upgrades
Participants explored AX25 version 2.2 protocol benefits, specifically selective reject features to minimize retransmissions. Future testing will utilize the AGW network interface to achieve necessary hardware requirements.
LoRa Technology Potential
The group evaluated LoRa radio technology for potential use in packet data networks and portable public service connectivity. No formal implementation strategy was established due to technical uncertainties regarding throughput.Next steps
[Ray Adkins] Update Slide Deck: Update the existing PDF slide deck to incorporate Texas Packet Radio Frequency Network integration details. Submit the finalized presentation to Steve Stroh for publication in the Zero Retries newsletter.
[Brian Webster, Pat] Develop FBB Instructions: Document the required forwarding rules for National Traffic System traffic on FBB Bulletin Board System platforms. Enable automatic message integration into the Digital Traffic Network.
[Brian Webster, Pat] Develop BPQ Instructions: Create setup documentation for BPQ software to handle National Traffic System traffic. Coordinate with system operators to ensure successful network integration.
[Charles Hargrove] Provide Routing Assistance: Offer technical guidance to Bulletin Board System operators for implementing packet routing configurations. Assist with troubleshooting specific setup issues.
[Brian Webster, Charles Hargrove] Create Speed Test: Design a specific file to measure performance improvements from version 2.0 to 2.2. Distribute this resource to allow users to verify speed gains.
[Brian Webster] Contact Craig Lamp: Discuss educational initiatives regarding connected packet modes with the DigiPie developer. Encourage the inclusion of these concepts in the project documentation.
[Brian Webster] Record Packet Audio: Visit a hilltop site to capture real-time audio of packet collisions and retransmissions. Use these recordings to create educational content.
[Charles Hargrove] Integrate BPQ Applications: Coordinate with Brad Brown to ensure BPQ software components are compatible with additional system environments. Adapt these tools for broader network use.
[Brian Wall] Send link: Provide information about mesh comm and the 433 MHz band via the mailing list.
[Brian Webster] Contact Jason: Discuss LoRa kiss mode and related use cases with Jason.
[Brian Webster] Research LoRa: Investigate how to utilize this technology for connected data networks rather than just APRS.
[Brian Webster] Draft suggestions: Write up proposed concepts regarding connected network builds and share them on the mailing list.
[Brian Webster] Resolve node issue: Check the K2PUT node status and discuss the connectivity problem with Ted offline.
[Brian Webster] Share meeting notes: Upload the meeting summary and documents to the EastNet mailing list.
Details
Meeting Access and Connectivity: Participants experienced technical difficulties joining the meeting, specifically regarding a login timeout issue that required a Google account for access (00:00:20). Brian Wall suggested that Brian Webster adjust host controls to allow broader access, which the group addressed to facilitate smoother entry for all attendees (00:03:48).
Introductions and Roll Call: Brian Webster [N2KGC] facilitated introductions for the meeting attendees, including Jim [KY2D], John Langner [WB2OSZ], Donald Gouin [K1 CMM], Charles Hargrove, Brian Wall [W1BKW], Misko [YT7MPB], Ted [K1 Y], Pat [WB2CMF], Ray Adkins [N3HYM], and Ray Quinn. Participants identified themselves by their call signs and geographical locations (00:06:46).
Tri-State Packet Radio Frequency Network Updates: Brian Webster relayed updates from Glenn [N3MEL], noting that the Tri-State Packet Radio Frequency Network has integrated artificial intelligence services for weather and call sign lookups, a National Traffic System radiogram generator, a Skywarn reporting generator, and a Winlink to packet gateway (00:13:53). The network has grown to 21 full-time hub stations, enabling coast-to-coast radio frequency packet messaging without internet reliance. The group also honored the memory of Jeff [KP3FT], a founding network member (00:15:09).
Digital Traffic Network Overview: Jim [KY2D] explained the function of the Digital Traffic Network, formerly known as the National Traffic System Digital. This network serves as the “long-haul” infrastructure for the National Traffic System, handling formal radiogram traffic via packet nodes (00:17:55). Jim described the standardized addressing system, which routes traffic by zip code to appropriate regions, allowing efficient integration between the Tri-State Packet Radio Frequency Network and the Digital Traffic Network (00:19:06).
Digital Traffic Network Test Results: Jim [KY2D] provided feedback on a recent test involving approximately 35 radiogram messages. While a few messages were delayed due to incorrect forwarding rules at specific nodes, the majority were processed successfully within a matter of hours, confirming the effectiveness of the current gateway process (00:20:31).
Strategic Integration of Networks: The group discussed the Digital Traffic Network’s role as a primary “on-ramp” for radiogram traffic. Jim [KY2D] noted that this integration allows participants to generate official traffic during events like Field Day for bonus points. Brian Webster proposed creating a slide deck to illustrate how these networks collaborate, aiming to increase awareness and utility across the community (00:25:04).
Instructional Materials for Network Users: Ray Adkins [N3HYM] offered a PDF presentation regarding the Digital Traffic Network, which Brian Webster recommended updating to include Tri-State Packet Radio Frequency Network integration. The participants aim to refine these materials to educate users on setting up proper forwarding rules for National Traffic System traffic (00:26:28).
Forwarding Rule Configuration: Participants discussed the technical requirements for configuring BBS software, specifically BPQ32 and FBB, to handle National Traffic System traffic automatically. Jim [KY2D] clarified the addressing syntax for BPQ32, and Brian Webster committed to assisting FBB users in implementing these configurations to ensure all systems can capture traffic correctly (00:28:42).
AX25 Version 2.2 Protocol Improvements: John Langner, author of Direwolf, introduced the improvements found in AX25 version 2.2. The protocol introduces a “selective reject” feature that allows the receiving station to request the resending of only the missing packets rather than retransmitting a full block of data, which greatly increases efficiency (00:33:54) (00:39:19).
Testing and Configuration Challenges: Charles Hargrove shared findings from a recent test where an AX25 version 2.2 connection failed because the systems defaulted to the older version 2.0. John Langner explained that this version requires modern hardware capabilities and sufficient memory to buffer up to 62 frames, which was not feasible in earlier decades (00:42:14) (00:45:43).
Interface Requirements for Protocol Adoption: John Langner clarified that the “selective reject” functionality of AX25 version 2.2 cannot be achieved through the KISS interface because KISS is designed to bypass the protocol’s connected mode logic. To fully leverage the version 2.2 improvements, users must utilize the AGW network interface (00:47:10). The group agreed to focus future testing on using the AGW interface to ensure the protocol works correctly (00:49:25).
Future Implementation and Speed Testing: Brian Webster and John Langner discussed plans to establish speed tests to demonstrate the efficiency gains of AX25 version 2.2 compared to version 2.0. The group aims to encourage broader adoption of these protocols by documenting the process and verifying performance improvements for 1200 baud and 9600 baud packet networks (00:51:31).
Nino TNC and Protocol 2.2: Brian Webster and John Langner discussed the Nino TNC, specifically regarding its support for version 2.2; John Langner noted that the device is primarily a KISS TNC. The participants agreed that implementing version 2.2 would improve performance for networks such as the Tarpon network (00:59:08). John Langner explained that implementing the connected mode protocol is a complex task due to the need for state management and queue handling, distinguishing it from simple KISS TNC operations (01:00:15).
Educational Value of 1,200 Baud Packet: Brian Webster emphasized the importance of 1,200 baud packet radio as a tool for teaching networking concepts, specifically “hidden transmitter syndrome,” which they noted is a common issue in unmanaged protocols like those used in LoRa mesh systems (01:00:15). Brian Webster suggested that users visit mountaintop sites to listen to the audio on radio digipeaters to better understand how packet collisions and retransmissions occur in real-time (01:01:31). Jim (+1 207-***-**98) supported this, noting that the slower speed allows users to hear acknowledgments and retransmits, making it an effective classroom tool (01:03:52).
Hamgate PBX System Status: Charles Hargrove provided an update that the Hamgate PBX system using Asterisk is currently operational following the closure of Hamshack Hotline. Charles Hargrove requested that any individuals managing Allstar repeaters contact them to discuss integrating those systems with the Hamgate PBX (01:07:37).
VPN Security and Segmentation: Charles Hargrove clarified distinctions between the ARDC VPN system and the Northeast/Hamgate VPNs. They explained that the ARDC VPN allows all traffic, including non-44net packets, placing the responsibility on the user to secure their system, whereas the Northeast VPN restricts traffic to 44net to maintain security (01:08:58).
AXIP and Dynamic IP Connectivity: Charles Hargrove reported that stations utilizing NetRom quality settings recommended in the NEA document have experienced increased reliability and throughput (01:08:58). However, they identified persistent connectivity issues for users attempting AXIP connections who lack static IP addresses and experience failures with dynamic DNS services after local ISP or cable modem resets (01:10:26).
Radiogram Routing and BBS Configuration: Charles Hargrove stressed the necessity of proper addressing and BBS routing configurations for the timely delivery of radiograms, noting that improper setups by inexperienced users can hinder network performance. Charles Hargrove and Jim are working with other DTN hub stations to clarify traffic handling procedures and encouraged users to consult the net directory available on the Radio Relay International website (01:11:46).
Direwolf Software Implementation: Brian Webster discussed the role of Direwolf in modernizing packet networks (01:13:15). John Langner explained that Direwolf is highly multi-threaded and uses different CPU threads for each audio interface, allowing it to support multiple simultaneous AGW connections if a source code variable is modified. Brian Webster expressed that this capability reinforces the potential for replacing legacy hardware TNCs with software-defined solutions (01:16:55).
Service Development and Bandwidth Efficiency: Brian Webster proposed using AI to offer guidance and service information to users on RF-only networks who may lack experience with command-line interfaces (01:20:43). Brian Webster also cautioned that when building services on 1,200 baud networks, developers must prioritize bandwidth efficiency to avoid “lazy” programming that could negatively impact performance (01:21:49).
Six-Meter Band Potential: Brian Webster advocated for re-establishing 1,200 baud 6-meter packet links as a viable alternative to the congested HF spectrum for building long-distance, full-time connections (01:21:49).
Chat Server Implementation: Brian Webster encouraged participants to implement chat services, such as HubNA, on local BBS systems to facilitate communication beyond a single local node (01:25:10).
LoRa and Digital Voice Integration: Brian Webster and Charles Hargrove discussed the potential of using Mobile Link TNCs and LoRa devices for digital voice protocols like M17 (01:26:22). Charles Hargrove expressed interest in using LoRa devices on 433 MHz for mesh networking, specifically to provide portable, handheld connectivity for public service events where operators may not be able to carry a laptop and TNC (01:27:37) (01:32:09).
LoRa Technical Specifications: John Langner noted that LoRa devices can function as KISS TNCs and offer adjustable performance through parameters like spreading factors and coding rates (01:33:00) (01:37:16). Charles Hargrove cited research from N7UV, who achieved data throughput of approximately 5 kilobits per second using a 125 kHz bandwidth (01:42:43). John Langner clarified that the confusion often stems from the difference between baud (symbol rate) and bits per second (data throughput) (01:44:03).
Instructional Strategies: Brian Webster emphasized the importance of incremental learning and using relatable analogies to explain new technical concepts to audiences without a networking background, rather than relying on theory from a “white sheet of paper” (01:47:55).
Future Planning for Connected LoRa Networks: Brian Webster requested further information on how to implement LoRa devices within connected data networks, as opposed to solely for APRS usage (01:49:00) (01:52:01). They noted that they have access to state-managed tower sites in New York and are seeking to modernize these networks with high-gain, point-to-point links (01:50:47).
K2PUT Connectivity Troubleshooting: Ted reported an inability to connect to the K2PUT node on 440 MHz despite testing their station with a 50-watt output. Brian Webster agreed to investigate the node status to determine if the issue originates at the K2PUT station or with the connection path (01:55:08).
LoRa Integration and AX25 Protocol: John Langner described an unsuccessful attempt to use a LoRa hat on a Raspberry Pi with Direwolf, despite having code to treat it as a built-in modem. Brian Webster questioned whether implementing the AX25 version 2.2 protocol would offer any advantages in this setup or if LoRa functions independently. John Langner clarified that LoRa is a distinct radio technology that serves primarily as a frame transport mechanism, indicating that the AX25 stack is not relevant to the underlying LoRa transmission (01:57:11).
LoRa Technology Characteristics: John Langner explained that LoRa was originally developed for the Internet of Things (IoT) to facilitate low-power, long-distance communication for small, occasional data messages. Brian Webster suggested that this technology could be leveraged within amateur radio, similar to how it is used commercially for devices operating on batteries or solar power (01:58:34).
Proposed Amateur Radio Packet Network: Brian Webster proposed a conceptual design for a packet network on UHF or 220MHz that adapts commercial LoRa gateway concepts for two-way amateur radio data. The proposal involves using LoRa gateways to allow data transmission to an internet-connected stream, similar to how the APRS system operates, but adapted for broader data use (01:59:40). Brian Webster expressed uncertainty regarding the throughput potential of such a system, questioning whether a model similar to 1200 baud packet radio could be achieved or improved upon (02:01:04).
Feedback on LoRa Gateway Concept: Brian Webster solicited input on the viability of using LoRa devices as gateways for an amateur radio data network (02:01:04). John Langner stated they lacked experience with LoRa gateways or the IoT-style implementation Brian Webster described (02:02:10). Ray Adkins N3HYM also indicated they had no experience with the technology (02:03:25).
Clarification of LoRa Gateway Functionality: Brian Webster outlined the commercial LoRa gateway model, where gateways on hilltops decode RF data and inject it into an internet stream for server-side retrieval. This was compared to existing APRS operations, where iGates serve a similar role by stripping and injecting packets into the internet (02:04:16). Brian Webster cautioned that LoRa gateways should not be confused with Meshtastic repeaters, as the former are specifically designed for internet-connected routing of commercial IoT data (02:05:34).
Meeting Conclusion and Next Steps: Brian Webster thanked the attendees for their input, specifically noting the value of John Langner’s contributions (02:06:44). It was confirmed that the meeting transcript and summary would be emailed and posted to the EastNet mailing list for review. The meeting concluded with an announcement that the next quarterly meeting will be held on a Thursday evening, with details to be shared via the mailing list (02:08:04).
EastNet Packet is one of the longest-lived and most active Packet Radio networks that I’m aware of in the US. Frankly, I’m envious of living in an area with so much Amateur Radio networking activity (though in fairness, I live in an area with a user-accessible microwave network - Puget Sound Data Ring (HamWAN). It was interesting to note EastNet Packet’s research into integrating LoRa links into the EastNet Packet network.
Kudos to President Brian Webster N2KGC and Webmaster Chris Lance WW2BSA for providing good documentation and publicity of the activities of both the group and the network.
Field Day PBX
Eric Grumling K0JEG on his Grand Valley Aviation (and sometimes, Amateur Radio) newsletter:
SIP phones, conference bridges, AllStar integration, and the Asterisk config files that made it work.
This is a followup (more of a sidebar, actually) from May’s article about the Field Day network. We’ll be going into the phone side of the network and how to set one up for your Field Day site, EMCOM communications trailer, or just a way to add some interesting features to your Allstar based repeater.
Allstar on a Raspberry Pi
I started off with the standard ASL3 Appliance image available at AllstarLink.org. I’m using a Pi CM4 with onboard eMMC storage. The board I’m using, the Tofu, is from a Swiss company called Oratek. This board is really nice because it can accept a very wide range of DC input from a coax power connector or two pin screw-down connector. It also includes an M.2 slot on the bottom, on which I installed an LTE modem. For an extra $8 they sell the .stl files for a case, which is functional but the top and bottom plates are pretty thin, so if you go this route make sure to bump up the infill to 75% or higher. I used standard PLA, so it will probably melt a little in a hot vehicle too (Update: It did melt pretty badly, along with the hot glue I used to hold things together).
The setup is powered by a DC-DC power supply that can provide 24VDC to run the MikroTik hAP3 router and mANT access point (on POE passthrough), and +12 to run the server. It also has a set of 18650 LiPo cells to keep the system powered up for some time if the primary power from my Ecoflow solar battery runs out. The Starlink Mini will be powered by its supplied 120V power brick because I’ve had issues with running it on the DC power supplied by the Ecoflow. I was using a USB-C PD adapter that should be supplying enough power to the Starlink terminal, but I’ve had some problems that look a lot like brownout issues that disappeared after I went back to the wall wart supplied.
There’s lots more Zero Retries Interesting detail in this story. I loved reading about all of it, and I love the synergy of setting up a multi-operator field day station with Voice Over Internet Protocol phones running on a “throw it online quickly” wireless local area network. Recommended!
FCC IDs Three Bands for Unlicensed D2D [Satellite Use]
D2D is satellite industry shorthand for Direct (satellite) to Device (mobile phone).
Jeff Baumgartner in Light Reading:
The FCC’s proposal to bring D2D connectivity to unlicensed wireless devices initially keys on three spectrum bands that are already being used for Wi-Fi, Bluetooth and other unlicensed use cases.
The FCC shed more light on a proposal to bring direct-to-device (D2D) connectivity to unlicensed wireless devices, and to possibly include laptops, smartphones and IoT devices that are already accustomed to connecting via unlicensed technologies such as Wi-Fi and Bluetooth.
The FCC announced the general concept last week, including an aim to seek out more than 225MHz of unlicensed spectrum for unlicensed D2D. Days later, it followed with a more in-depth, 38-page draft order that identifies a set of spectrum bands that will be explored, with the option to look into using other bands. The FCC is set to vote on the proceeding at its August 6 meeting.
The draft calls possible Earth-to-space operations in the following bands:
902MHz-928MHz
2400MHz-2483.5MHz
5725MHz-5850MHz
Those bands, the draft notes, are “currently available for use by unlicensed devices under Part 15 of the rules.” The Part 15 rules govern the operation of unlicensed devices, such as those supporting Wi-Fi and Bluetooth connections.
It’s going to be interesting for Amateur Radio’s (and unlicensed users / systems) use of these bands to “get used to the new (satellite based) spectrum users”.
Please direct comments / feedback about ZR > BEACON to the Zero Retries email list with the hashtag #ZR0258. Paid subscribers can comment directly on the web version of this issue.
Request To Send
By Steve Stroh N8GNJ
Editorial, Commentary, and Occasional Digressions
ZRDC 2026 Ho!
Zero Retries Digital Conference (ZRDC) 2026 will be here before we (I) know it.
12 weeks until Zero Retries Digital Conference 2026
on Friday, October 16, 2026,
in San Ramon, California, USA.
Our first three presenters for ZRDC 2026 are already confirmed, and we’re actively reaching out to a number of potential presenters that are working on Zero Retries Interesting projects or products or technologies. Tina and I cannot wait to tell you more in the next issue of Zero Retries.
2026 is Definitely the Year of OFDM in Amateur Radio
And with these new Amateur Radio data communications technologies, it seems likely that 2027 will be the year that a buildout of Amateur Radio networks that are relevant in the 21st century could begin.
Orthogonal Frequency Division Multiplexing - OFDM is fast becoming has become the buzzword / coolest technology in Amateur Radio data communications in 2026. It’s starting to eclipse Software Defined Radio, and at the moment, AI / ML in Amateur Radio is still a bit nascent.
I first became aware of how much difference using OFDM made in VARA FM (and VARA HF) a few years ago. Since then, I’m seeing OFDM spring up everywhere.
MT63
Ribbit / Rattlegram
FreeDV RADE (became prominent in 2026)
Mercury modem (released in 2026)
Hush modem
IP400 “Mode B” by IP400 on IP400 hardware and IP400 “Mode B” by Nino Carrillo KK4HEJ for implementation on the NinoTNC, targeted for release in 2026
Mesh Operations Protocol (MOP) (in development in 2026)
Others that have been mentioned to me under non-disclosure
And as of this week…
New Packet Radio - Next Generation (NPR-NG)
MODEM73
I… can’t… wait for some of these new capabilities to be completed and released for use. VARA FM works well. Ribbit / Rattlegram is pretty cool especially with its acoustic coupling and ability to use on any two way radio. FreeDV RADE is just an amazing leap forward for voice operations on HF. Hush and MOP look really interesting and seem to have energetic and motivated developers behind them. I keep hearing encouraging things about IP400.
It seems like beginning in 2027, we’ll have some significant technical capabilities to begin building substantive, fast, reliable, modern, and integrated networks on Amateur Radio spectrum:
Mercury modem for networking on HF,
IP400 for “lower speed” (on 12.5 kHz channels) VHF / UHF,
NPR-NG for “higher speed” on 420 - 450 MHz / 70 cm,
“AREDN-902” on 902 - 928 MHz / 33 cm,
AREDN on microwave.
All could be linked together with TCP/IP and perhaps even a unified (we can dream…) addressing scheme using either 44Net IP addresses or IPv6.
Weekends Are For Amateur Radio!
No Amateur Radio fun for me this weekend due to family activities. But August holds some promise for more time for Amateur Radio fun. My condolences to most of the rest of the continental US on their weather. Tina was shocked about the recent tornados in her hometown of Parsippany, New Jersey. In my hometown of Port Clinton, Ohio, tornados touching down was a summer Tuesday.
Have a great weekend, all of you co-conspirators in Zero Retries Interesting Amateur Radio activities!
Please direct comments / feedback about Request To Send to the Zero Retries email list with the hashtag #ZR0258. Paid subscribers can comment directly on the web version of this issue.
73,
Steve N8GNJ
Closing Thanks
My ongoing Thanks to:
Tina Stroh KD7WSF for, well, everything!
Jack Stroh, Late Night Assistant Editor Emeritus
Fiona and Shreky Stroh, Late Night Assistant Editors In Training
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Zero Retries 0258 was published on 2026-07-24. This issue was 10034 words.
Footnotes For This Issue
To see the relevant sentence for the footnote, just click the footnote number.
Preceded by LinHT 2.0, the release of Mercury modem, QuadRF.
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