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MONDAY EDITION: I took the weekend off the radio to catch up on working on the new chairlift for my wife. Of course I would not pay to have it installed, I mean how hard can it be?

Hard and heavy, it weights over 200 pounds and is 26 feet long. It is now put together, works fine, and the angles set for the  stairs but now I need a couple of young studs to help me get it in place to bolt it down...I might use it for a dumb waiter to bring down dishes and laundry....she does not need it all the time, it is just a safety precaution when she feels weak and I am not around....It might be good for carrying ham gear up and down the stairs...and now I need to install a vhf radio on it.

A Zinc Air Battery You Can Make Yourself

Zinc air batteries have been a familiar sight for decades in the world of photography, where they provided an environmentally less dangerous alternative to mercury cells. They operate by the oxidation of metallic zinc using air, and the zinc comes in the form of a paste spread between two electrodes. Can their astounding energy density be harnessed for something useful? [ZollerLab] has designed a zinc air battery to find out, and is using it to power a rudimentary model car.

The video below is in German so you’ll have to enable translated subtitles if you’re an Anglophone, and it’s very long. But it goes into extreme detail on the chemistry, construction, and constraints of a zinc-air battery, and describes the system in this design. It’s a stack arrangement, in which the cells are held together on threaded rods, and pushed into each other with springs.

We think the car model is intended to demonstrate that this battery chemistry might one day be used in automotive applications. It’s not such a far-fetched idea given the low cost, relatively low environmental footprint, and high energy density, indeed we’ve heard of similar experiments with aluminium primary cells. But in this case we can see it provides the hacker with another route for their experiments, and that’s no bad thing.

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SafecomLink Live AI Weather Over HF Radio

The following is a message from SafecomLink:

SafecomLink has published a new case study documenting live AI-based weather routing over HF radio north of the Arctic Circle. Sailor Harley Soltes (LA/KN7H) used SafecomLink with a Pactor 4 link to access the Safie AI assistant from his vessel off the Norwegian coast — establishing a connection to a land station in Austria (OE3FQU) on 14.120 MHz, then reaching the open internet, with no cellular coverage, no satellite service, and no shore-side infrastructure.

The real-time two-way AI conversation provided wind forecasts and a day-by-day crossing comparison for the passage to Lofoten, Norway. After completing the passage, Soltes reported the AI forecast was more accurate than his usual weather apps and far faster than the WinLink email method he previously used.

This is pretty game-changing — to have fast Pactor 4 communication from sea to a real-time internet AI connection. — Harley Soltes, LA/KN7H

Full case study: https://www.safecomlink.com/post/safecomlink-case-study-maritime

WEEKEND EDITION: Another rainy and stormy weekend, it could be one of those summers....

Autopsy of a Failed Vintage Carbon Resistor

Although resistors are hardly among the most exciting components, they are arguably one of the most important ones, as anyone who has done any amount of circuit design and debugging can attest to. So too with a single carbon resistor in a vintage Metrix oscilloscope that [CuriousMarc] recently repaired. After recapping the board there was still a major issue that got traced down to said resistor. After replacing it with a fresh resistor obviously this meant doing an autopsy to see why the old resistor had failed.

The 20 kOhm-rated resistor looked fine on the outside, with no obvious damage or discoloration, but it measured around 0.843 MOhm. To get to the insides [CuriousMarc] asked his friend [TubeTime] on how to proceed. The answer here was sandpaper and a lot of patience, and thus the experiment to see how much sanding it takes to get to the core of a fairly big resistor commenced.

Ultimately the insides were revealed, and they turned out to be rather interesting, with what looked like a glass tube filled with what would be the carbon-laden material between the two lead terminals. From poking around a bit at these insides it would appear that the failure mode was a degraded contact between these terminals and the carbon material. Considering that this resistor is many decades old and has gone through many thermal cycles and potentially various kinetic events some fractures are probably to be expected.

Perhaps most fascinating is the construction of this carbon resistor that looks to be a step above that of the average carbon resistor that [TubeTime] has taken apart over the years.

So Long, CHU, and Thanks for All the Time Signals

In the long ago, pre-internet days when your clock project wasn’t an ESP32 getting its timing via NTP over WiFi, it was still possible to build a wirelessly-updating clock. All you needed was a shortwave receiver tuned to a time signal — perhaps like the National Research Council of Canada’s CHU, found on the dial at 3330, 7850, and 14 670 kHz. At least, it can be found at those frequencies until June 22nd, 2026, when the station will finally go dark.

Depending where you were on Earth, it might have been easier to tune into CHU than the United States based WWVB, or one of the various European signals like DF44 or the UK’s MSF. If you’re not into radio, all these time signals have essentially the same job, if you hadn’t guessed: tell the time. This can be done in a variety of ways, and CHU has made use of more than one of them since its establishment in 1923.

Initially, the time was sent in Morse code, but later they added a speaking clock for easier human listening in both Canadian French and English. For synchronizing radio clocks, a series of pulses is given in DUT1 format using 0.3s pulses — which is what older clocks would have been listening to — and nowadays a digital FSK time code for more modern equipment. You can have a listen through the video by [Shortwave Listener] embedded below.

It’s not our place to judge the Government of Canada for trying to save money where they can. It wasn’t so long ago that WWVB was in danger of shutting down for similar reasons. But we’re still going to miss those beeps. If you do tune in before the station goes dark, CHU should still be giving out QSL cards. Get yours before it’s gone forever.

If you do have a clock that relies on this time signal, don’t worry. You can make your own, perhaps with a GPS time source.

Find the Right Rig: New Comparison Tool for ARRL Members

Amateur Radio Newsline Report

HAMSCI ASKS CANADA TO RECONSIDER SHORTWAVE SHUTDOWN

JIM/ANCHOR: Our top story takes us to Canada, where the popular shortwave time service, CHU, has been marked to go off the air later this month. A major citizen-science organization has asked officials to change their minds, as we hear from Travis Lisk N3ILS.

TRAVIS: The citizen science investigation organization HamSCI has asked Canadian officials to halt their planned shutdown later this month of its shortwave time-signal station CHU, saying it has unique and irreplaceable value to researchers and the international scientific community.

A statement on HamSCI's website praises CHU for its longstanding role as a resource in auroral research. Its unprecedented citizen-science study of the 2024 solar eclipse over North America also relied heavily on CHU's capabilities.

The statement says, in part: [quote] "The use of time standard beacons as ionospheric signals of opportunity dates back more than a century to the earliest days of radio science. Today, this time-tested approach is supercharged by inexpensive single-board computers, software defined radios, and the participation of the global amateur radio and shortwave listener community, who have built a growing meta-instrument that spans the continent of North America and points beyond." [endquote]

HamSCI’s flagship project, the Personal Space Weather Station Network, is also closely intertwined with CHU and its remote-sensing capabilities.

There was no statement released in response by the recipient, Dr. Marina Gertsvoff of the NRC.
**
NEW CREW BOARDS CHINA'S SPACE STATION

JIM/ANCHOR: Astronauts from one mission have returned to Earth and a new crew has arrived on board China's space station. We hear more from Jason Daniels VK2LAW.

JASON: Astronauts from China's Shenzhou-21 mission have returned to earth just days after the three-member Shenzhou 23 crew's arrival at the Tiangong Space Station. The Shenzhou-23 mission feature a first for any Chinese astronaut: one of the crew members is scheduled for an extended stay on board - remaining there for a year. In six months, the Tiangong station crew will also welcome an astronaut from Pakistan with the launch of the Shenzhou-24 mission. The Beijing-trained crew member will be the first international astronaut to visit the Chinese space station.

Tiangong is considered an important steppingstone in China's goal to land astronauts on the moon by 2030. The US space program is in a race with China's in the hopes of returning astronauts to the lunar surface in 2028.

Meanwhile, amateur radio is already there: In 2024, Japan's ham radio station, JS1YMG, became the world's first licensed ham radio station on the lunar surface.

**
UNLICENSED RADIO OPERATOR GETS NEWEST WARNING FROM FCC

JIM/ANCHOR: An unlicensed radio operator who has been convicted of jamming a local repeater several times has just been issued yet another FCC warning, as we hear from Kent Peterson KCØDGY.

KENT: Acting on several interference complaints from amateur radio operators in California, the US Federal Communications Commission has issued a warning to a radio operator who has a long history of unlicensed, disruptive and illegal transmissions on a local repeater.

The FCC sent a notice of unlicensed operation in late May to Jack Gerritsen of Bell, California, saying that in March, agents with direction-finding equipment had verified reports of his 2-meter transmissions on a local repeater. The FCC said that agents heard him make statements over the air, using the phrase "Jack is back," identifying himself.

Over the past two decades, Gerritsen's encounters with the the legal system and FCC have landed in him court -- and prison. He received a one-year sentence in 2000 following his conviction in state court of interfering with the highway patrol's radio system. Upon his release, he took and passed his Technician level exam, receiving the amateur radio callsign, KG6IRO. The FCC revoked the license grant days later, in November 2001, after realizing Gerritsen had been convicted of public safety interference and that the license was granted mistakenly. According to various reports, he remained an on-air presence despite that. FCC records show he was later sent a forfeiture order of $21,000 for interfering with Coast Guard Auxiliary Communications with a sailing vessel in distress.

He was convicted in September of 2006, at the age of 70, for malicious interference with radio and unlicensed transmissions. He was fined and sentenced to seven years in prison.

The latest notice from the FCC, dated the 28th of May, gives him 10 days to respond and orders him to immediately halt all transmissions.

**
NEW QUESTION POOL FOR TECHNICIAN CLASS EXAM

JIM/ANCHOR: This is a reminder to any candidates studying for the Technician Class Exam: A new pool of questions takes effect on the 1st of July. The question pool is to be used for any Technician exams being given after that date. The ARRL and the National Conference of Volunteer Examiner Coordinators reports that all major study materials have been updated to reflect the content of the new questions, which were released earlier this year.

(ARRL, NATIONAL CONFERENCE OF VECS)

**
DOUBLE CENTENNIAL FOR HAM RADIO IN JAPAN

JIM/ANCHOR: There's a lot to be said about being 100 years old and in Japan, amateur radio operators plan to say plenty on behalf of amateur radio, which is about to reach its centennial. Jim Meachen ZL2BHF tells us about plans for the celebration.

JIM: This year and next year are milestone years for ham radio operators in Japan. The Japan Amateur Radio League marks its 100th anniversary this month. The issuing of the callsign JXAX to Japan's first licensed amateur radio station marks its own centennial next year. In September of 1927, JXAX went on the air as an experimental shortwave radio telegraph and telephone station.

Now hams are setting aside the next 16 months to mark both moments in history. A full range of commemorative activities are planned from this month through to the 30th of September 2027. Operating events, awards and both the 2026 and 2027 Tokyo Ham Fairs, the world's largest ham radio event, are part of the plans, along with a commemorative publication and an opening ceremony.

So turn your attention, and maybe your antennas, toward Japan. Things are about to start happening.

**
REGISTRATION OPENS FOR MICROWAVE UPDATE CONFERENCE

JIM/ANCHOR: Many consider DXpeditioners to be the ultimate in radio adventurers and while that may be true in terms of geography, there is another landscape where radio adventurers are active and thriving - and welcoming newcomers. Andy Morrison K9AWM introduces them.

ANDY: The radio adventure that awaits beyond the realm of VHF and UHF can be found at 900 MHz and above -- on the microwave bands. Later this year, it will find a home off the air, for a few days, in Rochester, New York, where the Rochester VHF group is hosting Microwave Update, an international conference that draws 100 or more attendees. Registration began recently for the conference, which will be held on the weekend of October 23rd in a spacious state-of-the-art facility being made available at the L3Harris Conference Center in Rochester, New York.

Dave Hallidy, K2DH, one of the organizers, said that if you've had your eye on that higher part of the spectrum, now's the time to plan to attend the conference, which is hosted every year in a different city. He told Newsline [quote] "It's a friendly atmosphere. Everyone there are buddies." [endquote] Bill Rogers, K2TER, head of the committee, said there is also a lot of expertise and support among microwave veterans. In fact, in Rochester, many of them are current or former employees of L3Harris.

In addition to talks, there will be a tune-up clinic, and representatives from Keysight Technologies will be on site with their test equipment.

This is the Rochester VHF Group's third year hosting the conference, said another organizer, Ron Panetta, WB2WGH, and guests can take advantage of what the region has to offer. Less technical activities will take place at the nearby Doubletree by Hlton Hotel for a banquet and a flea market - and there will be a sidetrip on Thursday, October 22nd, to the Antique Wireless Museum.

To register, visit microwaveupdate dot org. That's microwaveupdate - one word - dot org. (microwaveupdate.org)

**
YOUNGSTERS PREPARE FOR IARU REGION 1 CAMP

JIM/ANCHOR: Young operators are getting ready for Youngsters on the Air summer camp in Region 1 of the IARU. Jeremy Boot G4NJH has an update.

JEREMY: Applications in the UK increased by 200 percent this year for a place in the Youngsters on the Air Summer Camp to be held in the Austrian Alps, according to the Radio Society of Great Britain. This year's session, organised by IARU Region 1's Youth Committee and the Austrian Amateur Radio Society ÖVSV [pron: "uhe fow ess fow"], will be held from the 25th of July through to the 1st of August. It is the 14th annual such camp, designed to build radio skills, foster international friendships and ensure a robust future for the next generation of hams. The RSGB has announced that it will be sending three campers: Tom, M1TJM, the 25-year-old team leader, with team members Filip, M7SZW and Milo, M9ILO, who are 16 and 17 respectively.
.
Last year, the camp was held in August just outside Paris.

**
WORLD OF DX

In the World of DX, the Radio Club Dominicano is marking its 100th anniversary with the callsign HI100RDC until the 15th of June. A team of operators will be on the air on 80-10 metres using CW, SSB and the digital modes. The club was founded on June 12th, 1926.

Olafur, TF1OL [Tee Eff Won Oh Ell] will be QRV from the island of Boa Vista as D4OL [Dee Four Oh Ell] from the 12th through to the 22nd of June. Listen for Olafur on the HF bands where he will be using FT8 and FT4.

Listen for Bo, OX3LX / OZ1DJJ, operating from south Greenland from the 12th through to the 24th of June. Bo will be focusing on 4m and 6m but may be found occasionally on HF.

Kasimir, DL2SBY is using the callsign 5H1KB until June 12th from Zanzibar Island, IOTA Number AF-032. He is using CW, SSB and FT8 on the HF bands and on 6 metres.

Listen for John, K9EL using the callsign FS/K9EL from St. Martin, IOTA Number NA-105, from the 10th through to the 24th of June. He will be using CW and FT8 on 80-10 metres. When 6 metres is open, you may find him there as well.

For QSL information and other operating details, please see each station's page on QRZ.com

(425 DX BULLETIN, DX WORLD)

**
KICKER: GOING EYEBALL-TO-EYEBALL, OFF THE AIR

JIM/ANCHOR: One of the best things to emerge out of the pandemic was proof that the ham radio community had resiliency as a social network. The pandemic has ended but one social network born during those years of isolation has remained strong. It’s called the Eyeball QSO Party, as Kevin Trotman N5PRE tells us in this week's final story.

KEVIN: It’s not a net. It’s not a ragchew. It’s not even on the air. The Eyeball QSO Party is a welcoming room on Zoom where hams from different countries simply show up. Once a week, they share their opinions, their experiences and even images on their computer screens. It could be a view of their treasured vintage rigs, their radio-controlled planes, astronomy gear or websites about the events in the news.

The QSO Party's host, Hugh Owen, KA3TTW, said he created the room during the pandemic to help ease isolation brought on by cancellation of club meetings, hamfests and even social morning coffees. The concept is simple, he said: People show up. Some are as local as the Washington, D.C. area where Hugh lives. Sometimes they're dropping by from Canada, Luxembourg, Great Britain or even Argentina.

Although getting on the air is why so many hams got their licenses to begin with, this off-air QSO Party still fills a need. Hugh told Newsline [quote] “This does have the big advantage of people being face-to-face and people can share things on their screens.” [Endquote] So every Monday, it happens starting at 1700 UTC between March 9th and November 2nd; and at 1600 UTC the rest of the year. :

Best of all, propagation is never an issue. Everyone gets a Five-Nine.

To join the party, send an email to eyeballqsoparty - that’s one word - at gmail.com. (eyeballqsoparty@gmail.com) There is also a groups.io reflector where you can visit and subscribe. Find the link in the text version of this week's newscast at arnewsline.org

FRIDAY EDITON: Another beautiful day on Cape Ann. Both of my sons have boats and mooring in Rockport and Gloucester, I am guessing the boats will be in after this weekend, the wx looks lousy on Saturday and the boat launch ramp will be busy with weekend warriors. It is worth bringing a lawn chair and a drink and watching folks make an attempt to back their boat down the ramp, some nearly launching their vehicles as well. Then the ramp rage starts with arguments between those launching and those waiting to launch and husband and wives blaming each other for poor directions. The only thing better is watching them try to get their boat back on the trailer later in the day where incompetence and alcohol play a huge role in the folly. I love Cape Ann.

THURSDAY EDITION: Fluctuating band conditions are the norm as summer propagation sets in....Field Day at the club has changed over the years, and it is disheartening that we have changed to a social food event.

I thought it was because we are all getting older but I don't believe that is the reason. 20-30 years ago we had club events on a local hill with several working stations, connected by a mesh network, rotatable beams on guyed ladders, catered food, and a first aid tent....and the majority of the members were over 65! The issue is the group today is over 65 too, they just don't want to get off their asses to do the work. We are a club of 120+ members with a clubhouse, a nice one!

This current bunch does not get on the air! We have 6 working stations at the club with multiple beams, etc for every band and mode....no one ever uses them! We have plenty of members join for meetings and coffee get togethers but the binding force is the food! These like to eat and bullshit the time away. I would guess maybe 12 of this entire group has HF stations that are active.

I am not complaining in anyway because this group is very generous, happy go lucky, and support the club financially over the top, we just aren't active on the ham bands it seems.....so we will have field day at the club facility again with a catered BBQ spread for mid afternoon and two stations running. One station on 10-20 and one on 40-75, with the 6 meter station available if the band opens up.

Number of Amateur Radio Operators in Japan Continues Decline

The number of amateur radio stations in Japan continues to decline. The Ministry of Internal Affairs and Communications announced the latest numbers for the first quarter of 2026 showing a steady reduction of 1,000+ stations each month. Over the last 10 years Japan's station count has reduced by more than 100,000 from 435,969 in January 2016 to 332,120 in January 2026.

While an explanation for the decline was not given, Japan has seen significant population loss over the last several years including a reduction of 3 million citizens over the past 5 years.

Start Planning for ARRL Field Day 2026

 

WEDNESDAY EDITION: Running late, I will update this afternoon

University of Utah’s TRIGA Research Reactor Set to Produce Electricity

Research reactors come in many forms and sizes, with the TRIGA class being commonly found at universities. The TRIGA reactor at the University of Utah was installed in 1975, and for the past half century the thermal energy it produced was bled off into cooling systems. Now for a world’s first, the reactor will be used to generate electricity instead.

What makes the TRIGA design so practical for small research reactors is its inherent safety due to the use of uranium zirconium hydride (UZrH) fuel, which imposes a strong negative thermal coefficient on the reactivity. Along with no need for any kind of containment, these pool-type, water-cooled reactors thus allow for a pretty good at the literal internals of the reactor core.

Their thermal power outputs range from 0.1 – 16 MWth, with the University of Utah reactor generating on the low end of the scale here, at 50 kWth. This energy will be partially used by a generator that has been developed by Elemental Nuclear, a startup company who looks to be trying to commercialize TRIGA fuel for microreactors with sodium coolant.

The installation at this TRIGA reactor should thus be seen as a proof-of-concept for Elemental Nuclear’s generator design, which uses a closed Brayton cycle with helium gas to generate an output of about 2-3 kWe from the ~13 kW generated by the turbine. This generated power will – of course – be used to power some racks with GPUs for ‘AI’ tasks. If successful, it could show the way for TRIGA-based microreactors to power datacenters.

– Hackaday Read More

TUESDAY EDITION: This is on my bucket list.....A brand-new edition of SWR Magazine is now available, built for radio amateurs who don’t just operate... but experiment, build, and explore the limits of communication. Website : http://www.swrmagazine.org

The closure of BBC long-wave

The BBC has announced that its long-wave service on 198kHz—currently transmitting BBC Radio 4—will close on 27 June 2026 at 1am BST.

The long-wave transmitters at Droitwich in Worcestershire, Westerglen near Stirling, and Burghead—overlooking the Moray Firth—will be closed that day.

The RSGB and the BBC Amateur Radio Group will be marking this occasion on the air and are looking for volunteers to activate a special call sign in the week leading up to and including the day of the closure.

In addition, three radio clubs have volunteered to activate special call signs to celebrate the almost-92-years of these historic transmitters on the day that they are finally turned off.

You can find more information on our website at rsgb.org/longwave-transmitters.

MONDAY EDITION: I had to shut off the radio yesterday during the 4pm session on 3928 because a quick storm blew thru here with torrential rain, lightning, and wind gusts over 40mph...quite a spell of shit wx here on Cape Ann...

He ended his statements, thanking ham radio for its courage and commitment, noting that Amateur Radio’s work strengthens our communities.

Senator Cruz is Chairman of the Senate Committee on Commerce, Science, and Transportation. His comments align with the American Radio Relay League’s (ARRL) ongoing efforts to strengthen and protect Amateur Radio’s role in emergency preparedness and public service communications.

Senator Cruz’s comments “reflect growing Congressional recognition of the value Amateur Radio Operators bring to communities across the country,” an ARRL spokesperson said.

The ARRL continues to advocate for legislation that protects and strengthens Amateur Radio’s role in emergency preparedness and public service communications.

WEEKEND EDITION:Cleanup Sunday, the yard is covered in branches and leaves from the 50+ mph winds yesterday that blew for 10 hours straight....the antennas are still up!

The Truth about the Hindenberg

The Hindenburg disaster recently marked its 89th anniversary, and [The History Guy] marked the event with a video that dispels many of the myths surrounding the airship. Example: the disaster did not actually occur on the airship’s maiden voyage. That isn’t true. The ship was on its 63rd voyage. However, it was the first flight of the 1937 season.

The giant ship burned because of the hydrogen gas inside, but the cause of the fire remains debatable and was likely not solely due to hydrogen. In fact, from a technical standpoint, the ship didn’t explode. It only burned.

Some of the myths are just from sloppy reporting or the tendency of people to misunderstand things. Others are a blurring in the common consciousness of the Hindenburg and the Titanic.

It is easy to think of the necessity for safe engineering when you are building, say, a bomb or a spacecraft. But anything capable of wreaking havoc requires careful design and testing. However, ships like the Hindenburg had made many trips without incident. Sure, the Hindenburg was a spectacle, but even the fatality rate was fairly low. Many of those who died jumped to the ground — they might have survived if they had waited a minute.

There are many myths around [Herb Morrison]’s famous “Oh the humanity!” report. We’ve noted before that it was played back at the wrong speed for decades. Airships have a stranger history than you might imagine.

From Spot to Map: A New Way to Follow DXpeditions

A new feature has been added to DXLook that allows amateur radio operators to visualize DXpedition activity on a world map using live reception reports from multiple amateur radio networks.

The new DXpeditions View combines data from PSK Reporter, Reverse Beacon Network (RBN), WSPRnet, and DX Clusters to display where DXpedition signals are being received in near real time. Rather than presenting reports as individual spots or entries in a cluster feed, the system plots activity geographically, providing operators with a broader view of how a DXpedition signal is propagating around the world.

DXpeditions often generate thousands of reception reports across multiple bands and continents. While traditional spotting networks remain invaluable, they can make it difficult to quickly understand the overall propagation picture. The new view aims to address this by transforming individual reports into a visual representation of global activity.

Operators can use the feature to identify which regions are hearing a DXpedition, observe changes in propagation throughout the day, and compare activity across different bands. Filters are available for both band selection and time range, allowing users to focus on current conditions or review activity over longer periods.

The feature is designed to complement existing spotting tools rather than replace them. By visualizing reception reports geographically, it becomes easier to identify developing openings, regional coverage patterns, and changes in propagation that may not be immediately apparent from spot data alone.

The DXpeditions View is available immediately and can be accessed from the Maps section of DXLook. For operators interested in learning more about how the feature works, a detailed guide is available on the DXLook blog.

DXLook is a free amateur radio platform that aggregates live data from multiple sources including PSK Reporter, WSPRnet, Reverse Beacon Network, DX Clusters, APRS, POTA, and SOTA. The platform was recently featured in the May 2026 issue of QST magazine.

DXLook -> https://dxlook.com

FRIDAY EDITION:  Another beautiful day in the neighborhood, 65 and sunny to start the honey list of errands....

Matching Transistors

Transistors in some circuit configurations work together and, frequently, need to be matched. This is so common that you can sometimes find ICs that are just a pair of transistors made with the same piece of silicon, so they should be matched very closely by default. But with discrete transistors, two devices of the same type are not always identical. [Learn Electronics Repair] covers the topic and explains how to match devices in the video below.

Depending on the circuit, the matching parameters may be different, but generally, the idea is that you want similar gains or matching saturation characteristics. The reason is that when you have multiple transistors working together, you don’t want one to do more work than the other device. This is inefficient and could drive the “better” component to fail.

The same idea applies in bridge circuits, where you might match resistors or capacitors to make sure that, for example, two 10% resistors are very close to the same value. A 10K resistor could be between 9K and 11K, and you might not care as long as they are both, say, 9.2K or both 10.8K.

This is different, by the way, from impedance matching, where you achieve maximum power transfer by matching a source to a load.

The world’s largest RC Boeing 777-9X takes flight

Popular YouTuber and aircraft enthusiast Ramy RC built and flew what he’s calling the world’s largest remote-controlled (RC) version of a Boeing 777-9X jet. It’s not just big for an RC toy, it’s big, period. 

With a wingspan of 33 feet and weighing 630 pounds, it’s roughly the same size as a human-piloted Cessna 150. The RC Boeing 777-9X may look  identical to the real aircraft on the outside, but the plane is made mostly out of CNC-milled foam and carbon fiber. It has five actuators controlling the flaps, working landing gear, and is fully electric. In testing, the behemoth was able to taxi around a tarmac, lift off, and land several times.

Ramy has made a bit of a name for himself in the over-the-top RC plane-building world. He started off building models on his kitchen floor with limited time and resources, and videos of those early builds took off online. His audience has helped him scale up and pursue increasingly ambitious RC plane designs full-time. To date, he has over 200 videos showcasing massive RC versions of a ViperJet, a Boeing 787-9, and a C-17 Globemaster. Ramy’s most recent build prior to the new Boeing was the world’s largest RC Airbus A380, which came in at a staggering 800 pounds with a 32-foot wingspan.

The Boeing 777-9X build started, like others, with a digital 3D model scaled down to 1/7 the size of the actual jet. With the proportions locked in, Ramy and his team then used a CNC mill to cut out separate foam parts for the plane’s fuselage, nose, and wings. Each section was reinforced with carbon fiber sheeting and sprayed with a thin layer of plastic for protection. Long runs of wiring were threaded through the plane to power systems like the wing flaps and landing gear doors. The whole aircraft is propelled by a pair of large electric ducted fans mounted where the real jet’s engines would sit.

Once assembled, Ramy used a remote control to taxi the plane around his outdoor tarmac. To drive home just how absurdly large the thing is, Ramy himself climbed on top and straddled his creation as it rolled around the facility. Once the team felt confident it was airworthy, they painted it white and blue with bold Boeing lettering along its side.

THURSDAY EDITION: 65 and sunny, good day to enjoy, look at the boat and decide it is two weeks away from dunking it....

 LiIon Battery Charger Failure

The popular LiIon battery chargers are frequently sealed in little black plastic cases and are not designed for field repair. When mine failed after 10 years of service I had to open it up for analysis.

The charger would blink red once and then remain off, unresponsive to mechanical shock. I knew the AC Mains were present but there was no DC output.

I opened the case with a hammer and chisel, it was easy, like cracking an egg.

 

 

Then I attached a LiIon cell and powered it up. Then I started to wiggle the input components, Inductors and capacitors. I heard a little ‘Crackling’ noise! Perhaps a capacitor charging or discharging. I moved it around until it started to work!  Success, the little Red Charging LED was on.  It was a mechanical fracture! A capacitor Just had a cracked solder joint.

Usually, the circuit board has mounting screws and is easy to get to the bottom side. You must remove the labels to look for any mounting screws. This one was glued down to the bottom of the case. I had to make an opening the lower half of the case to access the bottom of the circuit board. That requires a hole saw.  The cracked solder joint could easily be seen and was repaired.

 

 

There are many more cells to be charged from this little charger.

“The Symptoms will lead you to the truth, shot gunning will lead you astray.”

 

WEDNESDAY EDITION: The plan is to go to the club this morning, Elks for lunch, and then more yardwork. ...another 10-8 inch pots of flowers to seed and more mowing and raking. 1/2 acre of misery and I planted it all and fertilized it to boot....

USB-C Charger Juices Up 100 Devices At Once

Back when phones used to ship with chargers in the box, you’d get a plugpack that could charge one device. Aftermarket manufacturers eventually started making chargers with four or five ports which were great for travelling. But what if you wanted to charge even more devices? You might build something like this rig from [DENKI OTAKU].

The goal was to build a charger that could handle 100 devices at once. The charger is designed to charge devices at up to 1.5 amps. That’s no mean feat, as the device would have to be able to deliver 150 amps total when fully loaded. As for the actual design, though, it’s relatively simple. [DENKI OTAKU] simply built a simple USB-C charger PCB based around an off-the-shelf chip which has ten individual chargers on it, and stacked it up ten of those in a housing made out of aluminium extrusion. To deliver the current to run all these chargers, the rig got two massive switching power supplies to feed the charger array a massive amount of current. The open enclosure design here makes sense, in that it probably helps keep everything cool.

The only thing missing from the build video? A heavy-duty test. We’d love to see if it actually holds up under full load with 100 phones connected. We have some suspicions as to whether the traces on the PCBs would hold up under a continuous 15 amp load, for example. Still, if you wanted to provide phone charging en-masse at an event or similar, this kind of simple stacked design could be an easy way to go.

Phone chargers are still moving forward; the last big leap was the adoption of GaN technology. Video after the break.

The Vacuum Tube’s Last Stand(s)

When most people think about vacuum tubes, they picture big glass bottles glowing inside antique radios or early computers. History often treats tubes as a dead-end technology that was suddenly swept away by the transistor in the 1950s. But the reality is much more interesting. Vacuum tube technology did not simply stop evolving when the transistor appeared. In fact, some of the most sophisticated and technically impressive tube designs emerged after the transistor had already been invented.

During the final decades of mainstream tube development, manufacturers pushed the technology in remarkable directions. Tubes became smaller, faster, quieter, more rugged, and more specialized. Designers experimented with exotic geometries, ceramic construction, metal envelopes, ultra-high-frequency operation, and even hybrid tube-semiconductor systems. Devices such as acorn tubes, lighthouse tubes, compactrons, and nuvistors represented a last gasp of thermionic electronics.

Ironically, many of these innovations arrived just as solid-state electronics were becoming commercially practical. Vacuum tubes were improving rapidly right up until the market abandoned them.

The Pressure to Improve

By the 1930s and 1940s, vacuum tubes dominated electronics. Radios, radar systems, military communications, industrial controls, and the first digital computers all depended on them. But everyone was painfully aware of their problems.

Traditional tubes were fragile, generated heat, consumed significant power, and suffered from limitations at high frequencies. Internal lead lengths created parasitic inductance and capacitance. At radio frequencies and especially microwave frequencies, those unwanted effects made design difficult.

Military requirements during World War II accelerated development dramatically. Radar systems needed tubes capable of operating at VHF, UHF, and microwave frequencies. Vehicle equipment required devices that could withstand punishment. Computers with tubes suffered from frequent failures, took up entire rooms, and needed special cooling equipment, often bigger than the computer. These pressures drove tube designers into an intense period of innovation.

Acorn Tubes: Tiny Tubes for High Frequencies

One of the earliest major departures from conventional tube geometry was the acorn tube. Developed in the 1930s by RCA, the acorn tube got its name from its distinctive shape, which resembled an acorn with wire leads protruding from the base and sides. Unlike ordinary tubes, where the internal elements had relatively long leads, the acorn design minimized lead length to reduce parasitic capacitance and inductance. At high frequencies, this reduction was crucial.

One famous example was the 955 acorn triode. These tubes found use in experimental television receivers, military radios, and laboratory equipment.  Acorn tubes also reflected an important trend in late tube development: engineers were increasingly treating tubes not merely as amplifying devices, but as microwave structures requiring careful electromagnetic design.

The Lighthouse Tube

If acorn tubes were specialized, lighthouse tubes were positively futuristic. Lighthouse tubes abandoned the classic cylindrical glass form almost entirely. Instead, they used stacked disk-like electrodes arranged in a compact coaxial structure. The resulting geometry minimized transit times and parasitic reactances, allowing operation into microwave frequencies.

The tubes vaguely resembled a lighthouse tower. These tubes became essential in radar systems during World War II and the early Cold War period. Some lighthouse designs could operate in the gigahertz range, something impossible for conventional receiving tubes.

Their construction also introduced new manufacturing techniques. Many used ceramic and metal rather than large glass envelopes. This improved heat resistance and mechanical stability while reducing losses at high frequencies.
In many ways, lighthouse tubes represented the transition from classic vacuum tubes and true microwave devices like klystrons and traveling-wave tubes.

Metal Tubes and Ruggedization

Another path of tube evolution focused on durability and compactness. Early tubes used fragile glass envelopes that were easily broken and susceptible to microphonics and vibration. During the 1930s, manufacturers introduced all-metal tube designs. These tubes replaced the glass envelope with a metal shell, improving shielding and mechanical ruggedness.

Metal tubes were particularly attractive for military and automotive applications. Shielding reduced interference, while the smaller physical size allowed more compact equipment layouts.

Hybrid glass-metal constructions also became common. Engineers experimented constantly with new materials and packaging approaches to reduce noise, improve reliability, and extend tube lifespan.

Subminiature Tubes

One of the most impressive developments was the subminiature tube. These tiny devices often looked more like oversized resistors than conventional tubes. Some were less than an inch long and designed to be soldered directly into circuits rather than plugged into sockets.

Subminiature tubes emerged largely from military demands during and after World War II. Proximity fuzes for artillery shells required electronics small enough to survive being fired from a cannon. Traditional tubes would simply shatter under the acceleration.

The resulting ruggedized miniature tubes were shock-resistant and compact enough for portable military electronics. After the war, subminiature tubes appeared in hearing aids, portable radios, test instruments, and early miniaturized computers.

The Nuvistor: The Ultimate Receiving Tube

One of the most interesting late-stage vacuum tube was the RCA Nuvistor. Introduced by RCA in 1959, the nuvistor represented an attempt to create a truly modern vacuum tube for the transistor age.

Unlike classic glass tubes, nuvistors used a compact metal-and-ceramic construction. They were extremely small, highly reliable, vibration-resistant, and capable of excellent high-frequency performance. They also exhibited very low noise characteristics. At first glance, a nuvistor hardly resembles a traditional tube at all. You could easily mistake these for some other component in a metal can.

Technically, nuvistors were excellent devices. They offered superior performance in many RF applications compared to early transistors, particularly in television tuners, instrumentation, and aerospace electronics.

High-end studio microphones also adopted nuvistors because of their low noise and desirable electrical behavior. Some audiophiles still use nuvistor-based equipment today.

But despite their capabilities, nuvistors arrived too late. Semiconductor technology was improving rapidly. Silicon transistors were becoming cheaper, more reliable, and easier to manufacture in large quantities. Integrated circuits loomed on the horizon. The nuvistor may have been the best small receiving tube ever made, but it was competing against a technology whose economics would soon become overwhelming.

Compactrons

As semiconductor electronics advanced, tube manufacturers attempted another strategy: integration. The Compactron, introduced by General Electric in the early 1960s, combined multiple tube functions into a single envelope. A compactron might contain several triodes, pentodes, or diode sections in one package. This reduced component count, simplified wiring, and lowered manufacturing costs for television sets and other consumer electronics. Of course, tubes with multiple electrodes weren’t new. They dated back to at least 1926. However, GE’s aggressive marketing of the brand was an attempt to prevent designers from defecting to the solid-state camp.

In some sense, compactrons were the vacuum tube answer to integrated circuits. Engineers were trying to achieve greater functional density while keeping tube-based designs economically competitive. GE’s Porta-Color, the first portable color television, used 13 tubes, including 10 Compactrons. They usually have 12-pin bases and an evacuation tip at the bottom of the tube rather than at the top.

Compactrons saw widespread use in televisions, stereos, and industrial electronics during the 1960s and early 1970s. But again, semiconductor integration advanced even faster. The battle was becoming impossible to win.

Specialized Tubes Survived

Even after transistors took over consumer electronics, vacuum tubes remained important in specialized fields. Microwave tubes such as klystrons, magnetrons, and traveling-wave tubes continued to dominate high-power RF applications. Radar systems, satellite communications, particle accelerators, and broadcast transmitters all relied on advanced vacuum devices. In some areas, they still do.

A modern microwave transmitter aboard a communications satellite may still use a traveling-wave tube amplifier because tubes can handle very high frequencies and power levels efficiently.

No Instant Win

One misconception about electronics history is that the transistor immediately rendered tubes obsolete after its invention at Bell Labs in 1947. That is not what happened.

Early transistors had many limitations. They were noisy, temperature-sensitive, low-power, and expensive. Tubes often outperformed them in RF circuits, audio applications, and high-power systems well into the 1960s.

For a significant period, designers genuinely did not know which technology would dominate certain markets. Tube designers were still making substantial advances. Nuvistors and Compactrons were not desperate relics; they were serious engineering efforts intended to compete in a changing world.

Ultimately, however, semiconductors possessed overwhelming long-term advantages. Transistors required less power, generated less heat, occupied less space, and could be manufactured using scalable photolithographic processes. Once integrated circuits became practical, the economics shifted decisively. Vacuum tubes could evolve, but they could not shrink into millions of devices on a silicon chip.

The final years of vacuum tube development are often overlooked because history tends to focus on winners. Yet this period produced some of the most elegant and specialized electronic devices ever created. By the late tube era, vacuum tube manufacturing had become quite refined. Engineers could produce tubes with tightly controlled characteristics and surprisingly long operating lives.

Some early transistorized devices still retained subminiature tubes in certain high-frequency or low-noise stages because transistors had not yet surpassed tube performance in every application. This overlap period is often forgotten today. Electronics did not instantly switch from tubes to semiconductors. For years, many systems used both. For many years, a typical ham radio transmitter, for example, would be all solid-state except for the power amplifier finals, which were often a pair of 6146 tubes.

You can, of course, make your own tubes. If you’ve had enough of making your own tubes, maybe try reproducing some of these advanced models.

TUESDAY EDITION: Looks like a beautiful day, finally.The parade was rough yesterday for all involved with torrential rain during the miltary ceremony at the graveyard...What happened to all the radio operators?

BBC Long Wave Shutdown Special Event

The RSGB and the BBC Amateur Radio Group will be activating four special calls to mark the closure of BBC Long Wave transmissions on 198kHz (1500m) after more than 90 years. The Long Wave transmitters at Droitwich in Worcestershire, Westerglen near Stirling and Burghead overlooking the Moray Firth, will be closed down on 27 June 2026.

GB1500M will be active for one week from 21-27 June 2026 and may be activated from G, GM, GW, GI, GJ, GD and GU, by RSGB and BBCARG members over the period.
GB198LW will be activated by Cray Valley RS (England), GB198END by Moray Firth ARS (Scotland) and GB198KHZ by Stirling and District ARS (Scotland) during the week 21-27 June 2026.

Full details are on the RSGB website https://rsgb.org – search for “BBC Long Wave Shutdown.” A commemorative QSL card will be available for any QSOs or SWL reports via M0OXO OQRS.

Interview with the ARRL CEO: Remote Operating

 

WEEKEND EDITION: I just lit a fire in the stove, same as yesterday- 59 degrees on Memorial Day Weekend, and don't wish any veterans "Happy" Memorial Day...

EMAIL: Hi Jon,

Signals Without Borders

By Michael Kalter (W8CI) Xenia, Ohio

Hamvention 2026 drew a world of kindred spirits to the Greene County Fairgrounds — and reminded us that radio waves have always been humanity's most quietly miraculous language.

At a Glance

• Attendees: 30,000+ (official count pending)
• Countries represented: 43+
• Volunteers: 600+

---

It is finished — and already missed. The 74th annual Dayton Hamvention, held at the Greene County Fair and Expo Center in Xenia, Ohio, came to a close this past weekend, leaving behind a fairground full of memories, friendships renewed and forged, and a quiet sense of awe at just how far a radio signal can travel.

From the moment the gates opened on Friday morning, it was clear this year's gathering was something special. Crowds poured in from across the United States and more than 43 countries around the world — engineers and experimenters, retired servicemen and curious teenagers, seasoned DX chasers and brand-new licensees. Every walk of life. Every mode of communication. All converging on a single fairground in Greene County, Ohio, united by one invisible thread: the radio wave.

It doesn’t matter where you’re from — we can still have fun, talk on the radio, talk around the world, and just be friends. — Hazel Everetts, Assistant General Chairperson, Hamvention 2026

A gathering unlike any other

Hamvention is often called the world’s largest amateur radio convention, and the numbers bear that out. Thousands of attendees filled the exhibit halls, forums, and the sprawling flea market tucked inside the fairground’s horse track infield — with official final attendance figures still being tallied at the time of this writing. Over 350 vendor booths offered everything from brand-new transceivers to decades-old components, with 162 vendors representing the full spectrum of the hobby.

But statistics tell only part of the story. Walk through any aisle of the flea market, sit in on any forum, and you quickly understand that Hamvention is less about equipment and more about people. Friendships maintained year after year over the same crowded tables. Mentors passing knowledge to newcomers who didn’t know, six months ago, what a feedline was. Young operators discovering that this hobby has no ceiling.

Hamvention is the annual pinnacle event of our hobby. It is an honor to work with a great team to make this a successful event. Each year we work on improving the event. It takes a team of dedicated volunteers who share the passion and love of Amateur Radio. I encourage everyone that loves this hobby to get involved! — Jack Gerbs, WB8SCT · Hamvention 2026 Executive Committee

The next generation takes the stage

Among the most inspiring moments of the entire weekend was the Radio Club of America Youth Forum — a Saturday morning tradition that has run for more than three decades, and one that never fails to silence a room full of seasoned operators with nothing more than the enthusiasm of a ten-year-old at a microphone.

Founded and guided for many years by legendary amateur radio educator Carole Perry, WB2MGP — a Fellow and Director of the Radio Club of America, past Hamvention Ham of the Year, and ARRL Instructor of the Year — the RCA Youth Forum brought together carefully selected young ham radio operators, some barely out of elementary school, to deliver polished and passionate presentations on their work within the hobby. Topics ranged across the full breadth of amateur radio: satellite communications, high-altitude ballooning, antenna construction, digital modes, emergency preparedness, and the inspiring mission of bringing ham radio into schools and communities across the globe.

SPOTLIGHT — RCA Youth Forum

Each year, seven to eleven young operators — some as young as nine or ten — take the Hamvention stage to share their experiments, achievements, and passion for the hobby. The forum is consistently one of the most well-attended and warmly received events of the entire weekend.

The audience was captivated. Here were young people who had built their own antennas, chased DX across continents, bounced signals off the moon, and worked satellites passing hundreds of miles overhead — presenting their accomplishments not as hobbies, but as serious scientific and technical endeavors. The room was packed, and the applause was genuine.

The forum reached a remarkable crescendo when an astronaut took the stage to address the young presenters directly — urging them to dream bigger, reach farther, and recognize that the skills they were developing in amateur radio were the same skills that take human beings beyond the atmosphere. It was a moment that drew the connection between radio waves and space exploration into vivid, personal focus: a person who had orbited the Earth, looking out at a room of young operators who might one day follow a similar path.

The next generation of operators is already here — already curious, already building, already calling CQ.

For many in the audience, it was the single most memorable moment of Hamvention 2026. For the young presenters themselves, it may well have been the moment that set the trajectory of a lifetime.

The invisible world we inhabit

There is a particular joy in belonging to a community that understands what most people walk past without a second thought: that the air around us is alive with signals. Radio waves propagate through walls, across oceans, off the ionosphere, and out beyond the atmosphere entirely. Amateur radio operators don’t just use this invisible world — they know it, in a way that is almost devotional.

Every mode of amateur communication was on display at this year’s event. CW operators tapped out Morse code. Digital enthusiasts demonstrated FT8 contacts spanning continents on a fraction of a watt. Satellite operators tracked overhead passes. EME enthusiasts — moonbouncers — described reflecting signals off the lunar surface and catching the echo nearly three seconds later. The hobby, in its full breadth, is staggering.

From Xenia to interstellar space

No reflection on amateur radio and the wonder of electromagnetic communication would be complete without a thought toward the Voyager spacecraft. Launched in 1977 — the same era that shaped a generation of today’s operators — Voyager 1 is now more than 15.8 billion miles from Earth, deep in interstellar space, beyond the heliosphere, beyond the solar system itself. And yet we are still talking to it.

A radio signal sent from Earth today takes nearly 23.5 hours to reach Voyager 1. By November 15th of this year, the probe will cross a historic threshold: it will be a full light-day away — the first human-made object ever to reach that distance. A signal sent in the morning will arrive the following morning. A reply will not return until the day after that.

This is radio at its most humbling. The same fundamental principle — an oscillating electromagnetic field propagating through space — that lets a ham in Xenia, Ohio contact a counterpart in Tokyo is the very thing keeping humanity tethered to its most distant ambassador. The physics does not change. Only the distance grows.

• Distance to Voyager 1: 15.8 billion miles
• Signal travel time: 23.5 hours one-way
• In continuous operation: 49 years

600 volunteers, one community

None of this happens without the people who make it happen. More than 600 volunteers gave their time, their expertise, and their energy to produce Hamvention 2026 — directing traffic, staffing forums, manning information booths, setting up equipment, and doing the thousand invisible tasks that keep an event of this scale moving smoothly. They did it harmoniously, enthusiastically, and without any apparent desire for credit. That, too, is very much in the spirit of amateur radio.

The event also made a meaningful impact on the surrounding community. Hamvention generates an estimated $35 million in regional economic activity each year, filling hotels and restaurants and creating a visible surge of energy throughout Greene County. For the Miami Valley, this is not just a radio convention. It is an annual affirmation that Xenia, Ohio is, for one weekend in May, the center of a global conversation.

Until next year

The fairgrounds are quiet now. The vendors have packed their tables, the forums have ended, and operators from dozens of countries are making their way home — by plane, by car, by train — many of them already looking forward to May 2027, when Hamvention will return for its 75th year.

In the meantime, the radios will keep humming. Signals will keep traveling. Somewhere in the darkness between the stars, Voyager 1 will keep moving outward at 38,000 miles per hour, faithfully answering every call we send its way.

And somewhere in that audience at the RCA Youth Forum, a ten-year-old who just heard an astronaut tell them to reach for the stars is already thinking about what comes next.

We are a remarkable species. We built something that crossed into interstellar space, and we still talk to it every day. We gather by the tens of thousands to celebrate the art of sending a signal into the unknown. We do it peacefully. We do it joyfully. We do it together.

73, and we’ll see you in Xenia next May.

Encrypting Encrypted Traffic To Get Around VPN Bans

VPNs, Virtual Private Networks, aren’t just a good idea to keep your data secure: for millions of people living under restrictive regimes they’re the only way to ensure full access to the internet. What do you do when your government orders ISPs to ban VPNs, like Russia has done recently?  [LaserHelix] shows us one way Gopniks cope, which is to use a ShadowSocks proxy.

If you’re not deep into network traffic, you might be wondering: how can an ISP block VPN traffic? Isn’t that stuff encrypted? Yes, but while the traffic going over the VPN is encrypted, you still need to connect to your VPN’s servers– and those handshake packets are easy enough to detect. You can do it at home with Wireshark, a tool that shows up fairly often on these pages. Of course if they can ID those packets, they can block them.

So, you just need a way to obfuscate what exactly the encrypted traffic you’re sending is. Luckily that’s a solved problem: Chinese hackers came up with something called Shadowsocks back in 2012 to help get around the Great Firewall, and have been in an arms-race with their authorities ever since.

Shadowsocks is not, in fact, a sibling of Gandalf’s horse as the name might suggest, but a tool to obfuscate the traffic going to your VPN. To invert a meme, you’re telling the authorities: we heard you don’t like encrypted traffic, so we put encryption in your encrypted traffic so you have to decrypt the packets before you recognize the encrypted packets.

What about the VPN? Well, some run their own shadowsocks service, while others will need to be accessed via a shadowsocks bridge: in effect, a proxy that then connects to the VPN for you. That means of course you’re bouncing through two servers you need to trust not to glow in the dark, but if you have to trust someone– otherwise it’s off to a shack in the woods, which never ends well.

Don’t forget that while VPNs can get you around government censorship, they do not provide anonymity on their own. If, like tipster [Keith Olson] –thanks for the tip, [Keith]!– you’re looking side-eyed at your government’s “think of the children!” rhetoric but don’t know where to start, we had a discussion about which VPNs to use last year.

Icom Teases X-026 Radio to be Revealed at Hamvention 2026

In a reel posted to Facebook, Icom has teased a new radio, the X-026 to be revealed at Hamvention 2026. Dubbed as a "concept mock-up," the radio appears to be a mobile rig based on the focus of a vehicle through most of the video. The radio also appears to have a detachable faceplate and support multiple antenna inputs.

From hamlife.jp:

It is a separate machine that separates the main body from the main body and the operation part (display) from the image, and the operation part has four dials around the display (upper, lower and right), and the lower left part is a large size. From its shape, it seems to be a different model from the 144 / 430MHz band D-STAR / FM mobile machine "ID-5200" exhibited at last year's "Ham Fair 2025".

THURSDAY EDITION: Welcome to New England, 90 yesterday and 62 this morning at 8am......

BBC Long Wave Shutdown Special Event

The following is a message from Nick (G4FAL):

The RSGB and the BBC Amateur Radio Group will be activating four special calls to mark the closure of BBC Long Wave transmissions on 198kHz (1500m) after more than 90 years. The Long Wave transmitters at Droitwich in Worcestershire, Westerglen near Stirling and Burghead overlooking the Moray Firth, will be closed down on 27 June 2026.

GB1500M will be active for one week from 21-27 June 2026 and may be activated from G, GM, GW, GI, GJ, GD and GU, by RSGB and BBCARG members over the period. GB198LW will be activated by Cray Valley RS (England), GB198END by Moray Firth ARS (Scotland) and GB198KHZ by Stirling and District ARS (Scotland) during the week 21-27 June 2026.

Full details are on the RSGB website https://rsgb.org – search for “BBC Long Wave Shutdown.” A commemorative QSL card will be available for any QSOs or SWL reports via M0OXO OQRS.

Source: RSGB open_in_new BBC RSGB Special Event

How do erasers actually work? It’s surprisingly complicated.

Long before humans smacked “delete” to obliterate typos, we fixed mistakes and revised written language the old-fashioned way: by rubbing errors clean off the page.

The quintessential pink eraser is now a mainstay in household junk drawers, classrooms, and office supply cabinets, but how exactly do these ingenious little pieces of technology work? How do erasers erase?

The history of erasers

Humans have marked stuff with graphite for thousands of years. However, modern pencils—which encase graphite, or a mixture of graphite and clay, in wood—date back to the 17th century. 

Contemporary erasers, meanwhile, came fashionably late. Their precursors include balled-up stale bread and wax. Then, in the 18th century, natural rubber was used as an eraser. Later, in the 19th century, raw rubber erasers were toughened up with heat and sulphur. And, finally plastic erasers debuted in the 20th century. Whether erasers were snackable, heat-treated, or even electrified, the fundamentals of erasing remain. Pencils and erasers work together through the forces of attraction—and friction.

“When you run a pencil over paper, tiny little pieces of carbon flake off and stay on the paper, and that’s what leaves the pencil mark,” Dr. Joseph A. Schwarcz, a chemistry professor who directs the Office for Science and Society at McGill University, tells Popular Science. The pencil’s “lead”—a misnomer, as it’s not actually lead—isn’t just lodged between the fibers in paper; as graphite particles shear off, they also sit atop the page and remain there due to “a very small attraction between molecules,” Schwarcz explains. 

That’s where the eraser comes in, Schwarcz says. “There’s a greater adhesion of those little [graphite] particles to rubber than to the paper, so when you rub the rubber over the paper, it removes them.”

Several thousand years before colonizers commercialized rubber, Mesoamericans developed tools and recreational items with natural latex by tapping and processing the fluid in native rubber trees. While synthetic erasers, composed of substances such as polyvinyl chloride, are now more popular than natural rubber in some parts of the world, all erasers generally work the same way: “The graphite particles are attracted more to the eraser than they are to the paper,” says Schwarcz. 

“There’s also a slight abrasion effect, where you’re dislodging the graphite particles by friction,” Schwarcz adds. This process erodes some of the paper, which helps explain why so many different varieties of erasers exist; softer erasers tend to be gentler on the page, while firmer erasers are generally more durable and precise. 

The science behind the attraction

The chemical attractions Schwarcz describes are called van der Waals forces. “Molecules have tiny little charges distributed over the atoms, and the positive charges will attract the negative charges. So paper will have some molecules with negative charges that are attracted to the positive surfaces of the graphite,” Schwarcz says. Basically, when you write with a pencil, the graphite stays on the page thanks to forces of attraction.

But the attraction between graphite and paper is pretty weak. So when you rub an eraser on a piece of paper, friction basically disrupts the attraction between the graphite and the page, and the graphite that was once on the paper ends up sticking to the eraser.

On a molecular level, graphite is made up of many two-dimensional sheets of carbon, known as graphene, stacked one upon another and held together by van der Waals forces. 

“There’s this cloud of electrons on one layer of graphene, and another cloud of electrons on another layer of graphene,” Dr. Justin Caram, an associate professor of chemistry at the University of California, Los Angeles, tells Popular Science. The electrons on these sheets can “randomly fluctuate” to make one side a little positively charged, and the other a little negatively charged. 

“Because positive and negative charges interact with each other, that binds things together,” Caram says. In other words, we have van der Waals forces to thank for why graphite sticks together on a page.

Although individual sheets of graphene are “completely neutral and have no intrinsic dipole”—or inherently positive and negative side—“they still interact with each other because of these random fluctuations.” Caram adds, “That’s what a van der Waals force is. It’s basically a force between any two things where the electrons can move around and compensate for one another,” keeping things together—if somewhat weakly.

WEDNESDAY EDITION: Another beautiful day to get outside and do some yard and antenna work, get together at the club, and Elks for lunch...

DIY Nuclear Battery with PV Cells and Tritium

Nuclear batteries are pretty simple devices that are conceptually rather similar to photovoltaic (PV) solar, just using the radiation from a radioisotope rather than solar radiation. It’s also possible to make your own nuclear battery, with [Double M Innovations] putting together a version that uses standard PV cells combined with small tritium vials as radiation source.

The PV cells are the amorphous type, rated for 2.4 V, which means that they’re not too fussy about the exact wavelength at the cost of some general efficiency. You generally find these on solar-powered calculators for this reason. Meanwhile the tritium vials have an inner coating of phosphor so they glow. With a couple of these vials sandwiched in between two amorphous cells you thus have technically something that you could call a ‘nuclear battery’.

With an approximately 12 year half-life, tritium isn’t amazingly radioactive and thus the glow from the phosphor is also not really visible in daylight. With this DIY battery wrapped up in aluminium foil to cover it up fully, it does appear to generate some current in the nanoamp range, with a single-cell and series voltage of about 0.5 V.

A 170 VAC-rated capacitor is connected to collect some current over time, with just under 3 V measured after a night of charging. In how far the power comes from the phosphor and how much from sources like thermal radiation is hard to say in this setup. However, if you can match up the PV cell’s bandgap a bit more with the radiation source, you should be able to pull at least a few mW from a DIY nuclear battery, as seen with commercial examples.

This isn’t the first time we’ve seen this particular trick. A few years ago, a similar setup was used to power a handheld game, as long as you don’t mind waiting a few months for it to charge.

Blog – Hackaday Read More

DIY Weather Stations Report In From Chernobyl

You’re probably not going to hang out around Chernobyl any time soon. Still, knowing the conditions there can both satisfy your curiosity and provide scientific value. To that end, [Yury Ilyin] has spent the last couple decades installing homebrew weather stations across the Exclusion Zone for his own interest. 

The remote weather stations that [Yury] builds all follow a similar design. Each runs on three 18650 lithium cells, charged via a small solar panel. Most of these cells were salvaged from old laptop battery packs. These cells are used to power a GPRS or WiFi communications module, along with a temperature, humidity, and pressure sensor, and a Geiger counter, because, well… it’s Chernobyl.

He has been lucky enough to keep costs down by finding an old generation GPRS SIM card that could be cloned and used across multiple devices, and thus far has had no trouble receiving signals from his many distributed stations. He’s been able to use his sensor network to track the gradual decline of radioactive emissions in the area from Cs-137, as well as keep an eye on the local weather conditions in an area few ever tread.

[Yury] has built over two dozen of these devices, and several have passed the test of time—with the lithium cells and cellular hardware surviving both high and freezing temperatures as well as the ravages of rain and time. He’s continued to refine the design over the years, starting out with an ATmega644 running the show, and later upgrading to STM32 microcontrollers.

We’ve explored distributed radiation sensor networks before, too, as well as many a remote weather station.

TUESDAY EDITION: 80 at 8am, it is a good day to play in the yard and soak up some vitamin D..

2026 Hamvention Wrap-Up -- Weather or Not…

The ARRL Solar Update

New Display for Old Multimeter

As a company, Fluke has been making electronic test equipment longer than the bipolar junction transistor has been around for. In that time they’ve developed a fairly stellar reputation for quality and consistency, but like any company they don’t support their products indefinitely. [ogdento] owns a Fluke meter that isn’t nearly as old as the BJT but still has an age well outside of the support window, and since the main problem was the broken LCD display they set about building a replacement for this retro multimeter.

Initially, [ogdento] had plans to retrofit this classic multimeter with a modern OLED, but could not find enough space for the display or a way to drive it easily. The next attempt to get something working was to build a custom one-off LCD using a drill press as an end mill, which didn’t work either. But after seeing a Charlieplexed display from [bobricius] as well as this video from EEVblog about designing custom LCDs, [ogdento] was able to not only design a custom PCB and LCD display to match the original meter, but was able to get a manufacturer in China to build them.

The new displays have a few improvements over the old; mostly they are more stylistically inspired by later Fluke models and have a few modern improvements to the LCD itself. There were are few issues during prototyping but nothing that was too hard to sort out, such as ordering the wrong size elastomeric strips initially. For anyone who needs to replace a custom LCD and can’t find replacement parts anymore, this project would be a great starting point for figuring out the process from the ground up.