Category Archives: Ham Radio

Radio Waves: Radio Prague Special Broadcast, WNP Marks 100 Years, Ham Interference, and RTE on Longwave

Radio Waves: Stories Making Waves in the World of Radio

Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers. To that end: Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors David Iurescia, Ronnie Smith, Troy Riedel, Jack Dully, and the Southgate ARC for the following tips:

Radio Prague asks, “Would you like to be featured on our broadcast?” (Radio Prague via Facebook)

Our 85th anniversary is coming up on August 31st! We’re celebrating the occasion with a special broadcast that day and would love to hear from you – our listeners. If you’d like to send us your greetings, please record a message and send an audio file via email (to [email protected]) or Facebook. Due to time constraints, your recording should be around 30 seconds long. Please include your first name, where you live, how long you’ve been listening, and what you like most about Radio Prague Int’l.

We look forward to hearing from you!

Sailing Vessel with Ham Radio History Marks 100 Years (ARRL News)

The schooner Bowdoin is a century old this year. Now owned by the Maine Maritime Academy (MMA) as a training vessel, the ham radio history of the 88-foot (LOA) Bowdoin is often neglected. Constructed in Maine specifically for Arctic exploration, the vessel relied on amateur radio for communication during explorer Donald B. MacMillan’s Arctic Expedition of 1923 and on the MacMillan-McDonald-Byrd Expedition of 1925 — thanks in part to ARRL co-founder Hiram Percy Maxim, W1AW. The venerable vessel, the official vessel of the State of Maine and the flagship of Maine Maritime Academy’s Vessel Operations and Technology Program, recently underwent a complete hull restoration and refitting and has done a little touring to mark its centenary. Its home port is Castine, Maine.

The longwave transmitters MacMillan used on his earlier missions had proved “unable to penetrate the screen of the aurora borealis,” then-ARRL historian Michael Marinaro, WN1M (SK), explained in his article, “Polar Exploration,” from the June 2014 issue of QST. In 1923, MacMillan turned to ARRL for help in outfitting his next expedition with better wireless gear. Marinaro recounted, “It was enthusiastically provided.” Maxim and the ARRL Board recruited Donald H. Mix, 1TS, of Bristol, Connecticut, to accompany the crew as its radio operator.

M.B. West, an ARRL Board member, designed the gear, which was then built by amateurs at his firm, Zenith Electronics. The transmitter operated on the medium-wave bands of 185, 220, and 300 meters, running 100 W to a pair of Western Electric “G” tubes. Earlier exploratory missions had used gear that operated on longwave frequencies. The shipboard station on board the Bowdoin was given the call sign WNP — Wireless North Pole. [Continue reading…]

The Machines That Built America (History Channel)

In 1893, sending information across America is a time-consuming process. Letters travel slowly by land, and those who can afford it, send telegrams along a limited network of fixed wires. But two rival inventors have the same idea for improving things: wireless communication. Nikola Tesla is one of the most famous and successful thinkers of his day, single-handedly changing the way electricity is supplied and generated. Guglielmo Marconi is a young, uneducated Italian inventor who ignores scientific consensus and goes with his gut. Both want to rid the world of wires and send messages through the air. With millions of dollars on the line, the two men battle to dominate the new market and bring radio to the masses. [Click here to view episode on the History Channel.]

Woman fights to have ham radio operations banned after potential interference with insulin pump (WFTV)

MARION COUNTY, Fla. — A Marion County woman is taking on her neighborhood association, in a matter she said puts her health at risk.

Michelle Smith, a Type 1 Diabetic, and a consultant determined that her neighbor’s ham radio hobby might have interfered with the doses of insulin being pushed out from her pump.

The 55+ community where she lives hired that consultant and told the neighbor to shut down his amateur radio station.

But a copy of the community’s rules shows a change was put in place that could pave the way for other similar antennas to be installed.

9 Investigates learned that Smith’s complaint went all the way to the state level.

She wants the Florida Commission on Human Relations to make a determination whether the community’s board and management is doing enough to protect her and others with medical devices.[…]

RTE on long wave 252 kHz back on air (Southgate ARC)

RTE carried out essential maintenance of the Long Wave transmitter in Clarkstown, Co. Meath for two months during which period RTE Radio 1 was not available on 252 kHz.

This essential maintenance of the transmitter was due to be carried out in 2020, but was postponed due to Covid-19 restrictions. For the health and safety of those carrying out the works, the transmitter had to be switched off for the works period. Any overhaul has to be completed during the summer months when there is good light and weather conditions.

Transmissions commenced once again last Monday with an output of 500 kiloWatt during daytime and 100 kiloWatt at nighttime.

During this shutdown, one could receive Radio Algeria transmitting on the same frequency with 1.5 megaWatt during the day and 750 kiloWatt at night, broadcasting a varied program.

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Radio Waves: Radio Hats, FCC Fees in 2022, Ham Saves Friend’s Life, and Monitoring the fall of the Afghan Government

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Radio Waves: Stories Making Waves in the World of Radio

The story of the Radio Hat, 1949 (Rare Historical Photos)

In 1949, Victor Hoeflich held a press conference to introduce the “Man from Mars, Radio Hat”. Hoeflich knew a picture would tell the story so he had several teenagers modeling the radio hats for the reporters and photographers. Soon pictures and news stories appeared in newspapers coast to coast. The articles typically included a photo of a young lady wearing the hat and a six-paragraph story.

Although the radio hat had a futuristic appearance at the time, this was in fact due to technical limitations. While the transistor had been invented in 1947, it was still experimental and not widely available. The hat’s radio relied on vacuum tube technology, and Hoeflich made the tubes a prominent feature, as well as the loop aerial. The tuning knob sat between the two valves. The battery was carried in the user’s pocket.

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Jock discovers the joys of ATS tuning with the C.Crane CC Skywave SSB

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Many thanks to SWLing Post contributor, Jock Elliott (KB2GOM), who shares the following guest post:

Really cool trick the CCrane Skywave SSB will do — the “radio butler”?

To paraphrase Ratty from Wind in the Willows: ” “Believe me, my young friend, there is nothing–absolutely nothing–half so much worth doing as simply messing about with radios.”

That is precisely what I was doing . . . messing, simply messing about with the CCrane Skywave SSB.

Then I observed something. Just above the LIGHT button is some lettering: “ATS.” Not having taken notice of it before, I looked it up in the manual. It stands of Automatic Tuning System, and the manual says this about it:

“This feature programs all receivable stations in the AM, FM, Air and Shortwave bands to memory buttons. To use ATS, select your desired band: AM, FM, Air or Shortwave, and press and hold the ATS button for two seconds. The CCrane Skywave SSB will scan the entire band and automatically set all available stations in sequence 1-20. If more than stations are available, then the remaining stations will be preset to the next memory page, and so on.”

So I tried it; I punched in a shortwave frequency — 9250 — and pressed and held the ATS button for two seconds. The Skywave then muted itself and went to the bottom of the shortwave bands — 2300 — and started silently scanning through all of the international shortwave bands, hopping from one shortwave band to the next. Occasionally it would stop and silently store a frequency. After a while it stopped, unmuted, and began playing the very first memory that it stored. I checked the other memories that were stored and — sonofagun! — there were stations stored in each memory. Some of them were really faint, and I had to mess with single sideband and bandwidths to make them fully copyable, but they were there, automatically scanned and stored by the CCrane Skywave SSB. Obviously, you might want to repeat the ATS scan as shortwave propagation changes, say, from day to night.

Well, I thought, would it do it also for Air frequencies? Short answer: it certainly will. And it will do the same for AM, FM, and — get this — if you put the Skywave SSB in single sideband mode, it will scan the ham bands, automatically changing sidebands appropriately as it hops from ham band to ham band. Note: when you check the memories stored during an ATS ham band search, you may not find anything there, simply because ham transmissions come and go much more often than international broadcasters.

There is one downside to the ATS function. When the Skywave scans and stores stations, it does so starting at Page 1, Memory 1 of the memory system . . . always. So, if you scan the Shortwave frequencies and store frequencies they will be stored starting at Page 1, Memory 1, wiping out anything that you have already stored there. If you then use ATS on the Air band, it will then write over whatever you stored from the Shortwave frequencies. I wish there were a way for the user to designate at which page in the memory system ATS will begin storing frequencies so that the information stored starting at Page 1, Memory 1 is not constantly overwritten.

However, there is another trick the Skywave will do: if you have used ATS to scan and store Air frequencies in Page 1 of the memory system (which it does automatically), you can then press and hold the UP and DOWN buttons at the same time, the Skywave will then scan through the Air frequencies that are stored there. Further, there is a squelch function on the Skywave that works only on the Air frequencies. So, with a little persuasion (very little), the CCrane Skywave turns itself into a civilian air scanner.

The ATS function on the CCrane Skywave SSB is a bit like having a radio butler: “I say, Jeeves, find me what’s on the air this evening.” A short while later, Jeeves reports back: “Here you are, sir, I found 10 shortwave stations you might like to listen to.”

Frankly, I don’t know if other modern shortwave portable radios offer a similar function, but if you have a CCrane Skywave SSB, give the ATS function a try; it’s pretty slick.

— Jock Elliott, KB2GOM

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Radio Waves: 8 Meter Experimental Station, Forgotten Music Festival Found, Press Freedom Fear in Poland, and JA1TOKYO

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Radio Waves: Stories Making Waves in the World of Radio

8-Meter Experimental Station on the Air from the US (ARRL News)

WL2XUP is an FCC Part 5 Experimental station operated by Lin Holcomb, NI4Y, in Georgia. It’s licensed to operate with up to 400 W effective radiated power (ERP) between 40.660 MHz to 40.700 MHz.

John Desmond, EI7GL, reports that as of mid-July, WL2XUP was intermittently transmitting on Weak-Signal Propagation Reporter (WSPR) on 40.662 MHz (1500 Hz) for 2 minutes out of every 10, with an output power of 20 W ERP into an omnidirectional antenna. For FT8 check-ins and tests, an ERP of 100 W may be used. The band is affected by several propagation modes, including tropospheric ducting, sporadic E, transequatorial propagation (TEP), and F2 propagation. As Desmond notes, the 40 MHz band will open a lot earlier than 50 MHz and could be a useful resource for stations monitoring the transatlantic path.

A 2019 Petition for Rulemaking (RM-11843) asked the FCC to create a new 8-meter amateur radio allocation on a secondary basis. The Petition suggests the new band could be centered on an industrial-scientific-medical (ISM) segment somewhere between 40.51 and 40.70 MHz. The spectrum between 40 and 41 MHz is currently allocated to the federal government and, as such, within the purview of the National Telecommunications and Information Administration (NTIA).

ARRL member Michelle Bradley, KU3N, of Maryland, filed the petition on behalf of REC Networks, which she founded and described in the Petition as “a leading advocate for a citizen’s access to spectrum,” including amateur radio spectrum.[…]

An Indiana radio host found the last recording of a forgotten Evansville music festival (Evansville Courier & Press)

Inside a little shed in southwest Indianapolis, Kyle Long found something almost “too amazing to be true.”

It was some time in the early 2000s. Like he often did during his teenage and 20-something years, Long was trolling a garage sale for old music. He mainly worked as a club DJ back then, and he loved to pepper his sets with songs miles away from the top 40. If they had a connection to Indiana musical history, even better.

What he held his hands that day definitely did. It was a reel-to-reel tape. “61 jazz fest” was scrawled in the cover’s top-left corner, and Long noticed names like “Duke Ellington” written on the packaging.

He kept the tape at home for years before finally getting it digitized. That’s when he discovered he owned what is perhaps the last known recording of a star-studded – and ultimately doomed – Evansville music festival.

Thanks to a brash promoter, unlikely sponsors, and fallout from the actions of drunk teenagers 1,000 miles away, Evansville hosted what became known as the Indiana Jazz Festival in 1960 and ’61. Stars such as Ellington, Benny Goodman, the Staples Singers, Dave Brubeck and the future Lando Calrissian himself, Billy Dee Williams, whipped Roberts Stadium into a froth on hot summer weekends that attracted local residents and college kids from around the country.

CBS recorded snippets of the 1960 show. And in ’61, promoter Hal Lobree claimed the U.S. State Department planned to film the festival and turn it into a documentary called “Americana Indiana” that would be broadcast on the government-owned Voice of America.

Lobree dreamed it would become our version of the Newport Jazz Festival: the legendary yearly concert that, like its folk-singing cousin, still generates mountains of tourist cash for the small Rhode Island city.

But by 1962, the Indiana Jazz Festival was gone.[Continue reading…]

Poland: Media freedom fears as TVN24’s licence extension is suspended (Euro News)

Poland’s National Broadcasting Council has suspended the extension of the licence of the independent TVN24 television channel, which is owned and financed by an American company.

Negotiations are also underway in parliament on a new bill that would limit the ability of media to operate in Poland if they have large foreign investment.

If the bill goes through, TVN would fall into that bracket since it’s part of the American Discovery franchise.

Press Club Polska, an independent association of journalists, said the decision is an attempt to strangle media.

“In our opinion, the move to not extend TVN’s licence seems to be an attempt to put pressure on independent media,” explained Wojciech Tumidalski. “When it comes to this “lex TVN” bill, as they call it, it is unacceptable to pass a law against a single economic entity that plays an important role in the media market and is simply an independent medium that challenges the government.”[…]

Olympic Games – JA1TOKYO is on the air (Southgate ARC)

On July 16 JARL opened the special commemorative station ‘JA1 TOKYO‘ in Nishitokyo City, Tokyo, to commemorate the Tokyo 2020 Olympic and Paralympic Games being held from July 23

After the opening ceremony of “JA1TOKYO”, an operator in charge was assigned to each band for active operation.

In the evening, a member of Japan’s House of Representatives Hirohiko Izumida 7K1KJK, who is an amateur radio operator and a member of JARL, attended the venue and operated the station in the 7 MHz band.

The station will be active until September 5.

Source JARL https://tinyurl.com/IARU-Japan

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Radio Waves: 20K Hz & The Buzzer, Cuba Jamming, Rugby Radio Station soon a school, HRO Opens a store in FL, Police Use Morse, Tool Box Spy Radio, and “Einstein Listened”

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Radio Waves: Stories Making Waves in the World of Radio

Many thanks to SWLing Post contributors Paul, David Goren, Pete Polanyk, Ulis Fleming, Troy Riedel, Tracy Wood, Dan Robinson, and Kris Partridge for the following tips:

The Buzzer (Twenty Thousand Hertz podcast)

This episode was written and produced by Olivia Rosenman.

Since World War I, countries around the world have been broadcasting mysterious numerical messages via shortwave radio. Though concrete evidence is hard to come by, the general consensus is that these coded messages are meant for undercover agents operating abroad. And one particular Russian station may have an even more sinister purpose. Featuring computer engineer Andrus Aaslaid, historian Maris Goldmanis, and documentary photographer Lewis Bush.

Cuba Jamming Ham Radio? Listen For Yourself (IEEE Spectrum)

A public SDR network triangulates the island as the source of mystery signals

By Stephen Cass

As anti-government protests spilled onto the streets in Cuba on July 11, something strange was happening on the airwaves. Amateur radio operators in the United States found that suddenly parts of the popular 40-meter band were being swamped with grating signals. Florida operators reported the signals were loudest there, enough to make communication with hams in Cuba impossible. Other operators in South America, Africa, and Europe also reported hearing the signal, and triangulation software that anyone with a web browser can try placed the source of the signals as emanating from Cuba.

Cuba has a long history of interfering with broadcast signals, with several commercial radio stations in Florida allowed to operate at higher than normal power levels to combat jamming. But these new mystery signals appeared to be intentionally targeting amateur radio transmissions. A few hours after the protest broke out on the 11th, ham Alex Valladares (W7HU) says he was speaking with a Cuban operator on 7.130 megahertz in the 40-meter band, when their conversation was suddenly overwhelmed with interference. “We moved to 7170, and they jam the frequency there,” he says. Valladares gave up for the night, but the following morning, he says, “I realize that they didn’t turn off those jammers. [Then] we went to [7]140 the next day and they put jamming in there.”[…]

New school at home of former radio station on track for autumn launch (Coventry Telegraph)

Houlton School, where Rugby Radio Station once stood, is set take its first influx of pupils in September

Plans for a new school at the historic former home of Rugby Radio Station are being fine-tuned and remain on track for a September start.

Houlton School, which will be named after the town in America that received the first transatlantic voice broadcast from Rugby Radio Station in 1927, will take its first influx of 180 Year 7 pupils this autumn.

The school, which forms part of the 6,200-home urban extension in Houlton, east of Rugby town centre, will take a new year group of 180 pupils every 12 months.

Michael McCulley, the school’s Principal Designate, said: “Whilst building a fantastic £39m new school during three lockdowns has had its challenges, we are also acutely aware that we have had a completely blank page from which to develop our exciting curriculum and pastoral programme.

“This freedom has been important as we have needed to evolve to the changing needs of our first group of students.[…]

Ham Radio Outlet to open store in Florida (Amateur Radio Newsline)

Ham Radio Outlet, the nationwide amateur radio retailer in the US, has announced that its ongoing expansion plans will include a store in the state of Florida. The new store will join 12 already open in such states as California in the West, where the company is based, to Delaware in the East, Arizona and Texas in the South, New Hampshire in the North. The company’s announcement on social media set off a wave of speculation about the new location, especially on Instagram where the company wrote, “We’re not telling yet! We’re open to suggestions.” The closest Ham Radio Outlet to Florida is in Atlanta, Georgia. The company, which calls itself the world’s largest supplier of amateur radio equipment, is also known for shipping internationally.

Old is gold: In times of satellite & internet, Pune cops keep Morse Code in use as a robust stand-by communication mode (The Indian Express)

Every Sunday, an operator with Pune Police’s wireless wing sends a Morse Code message to the office of the Director General of Police, Maharashtra.

IN THE era of satellite communication, which involves transmitting signals into space and back, and internet based systems transferring gigabytes of data in a flash, police have kept alive the age-old system of Morse Code – a primitive method of sending messages in the form of dots and dashes.

Every Sunday, an operator with Pune Police’s wireless wing sends a Morse Code message to the office of the Director General of Police, Maharashtra. While this is their way of paying tributes to one of the earliest modes of telecommunication, it is primarily a way of maintaining a robust stand-by mode of message delivery in case all other means of communication fail.

Pune City police have recently started a series of tweets featuring the communication systems used by the police and their evolution till date. On Sunday, Pune Police Commissioner Amitabh Gupta tweeted, “As an ode to the beginning of wireless communications, the Commissioner’s Office still uses Morse Code to transmit Messages every Sunday.”[…]

Antiques Roadshow: Spy radio disguised as toolbox found in garden shed worth huge sum (The Express)

ANTIQUES ROADSHOW saw a World War II spy radio which was disguised as a toolbox fetch a huge valuation when it travelled to Kenilworth Castle.

Antiques Roadshow’s expert Mark Smith marvelled at the ingenuity of a spy radio which was used in World War Two in a recent episode. The item, from the outside, was made to look like a toolbox but when opened, displayed a detailed radio which could be “powered by any source”. So how much was it worth? Mark put a £10,000 to £15,000 price tag on it.[…]

Einstein Listened (WNYC)

Former WNYC director Seymour N. Siegel suggested that WNYC once received fan mail from Einstein. As I continue to look far and wide for evidence of this alleged bit of praise, I can’t help but wonder, what broadcast prompted the great man to write? Alas, so far, the document has eluded me. But, we do know that the father of the theory of relativity was a subscriber to both the WNYC and WQXR program guides. And we have no less than Erwin Panofsky, the noted German-American art historian and friend of Einstein’s, to thank for that.

It all began when the distinguished gang at the Institute for Advanced Study in Princeton, New Jersey decided to chip in and build the Nobel laureate a “high-fidelity” radio for his 70th birthday. The 1949 gift included subscriptions to the WNYC, WQXR, and WABF program guides.[…]

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Radio Waves: Keeping CA Wildfires at Bay, 50 Years of KNOM, 24-Hour Saudi Radio Urdu Service, New Comms for Navy Subs, and North Korea Cracks Down on TV

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Radio Waves: Stories Making Waves in the World of Radio

Many thanks to SWLing Post contributors Peter Abzug, David Iurescia, and Dan Robinson for the following tips:

How A Group Of Dedicated Volunteers Are Keeping California’s Wildfires At Bay (NPR)

The Los Angeles Fire Department depends on help from amateur radio volunteers when fire threatens communications infrastructure. NPR looks at how ham radio operators are keeping residents safe.

50 years of KNOM Radio Mission (KNOM)

Whether you’ve been with us since the beginning, or you’re just getting to know us: it’s you, and your faithful support, that has made KNOM America’s oldest Catholic radio station. Thank you!

KNOM has been broadcasting in Western Alaska since July 14th, 1971, when the station could first be heard in Western Alaska.

The continuing mission has been possible only by the hard work, sacrifice, dedication, and love of thousands of people: our staff and volunteers, listeners and community members, and thousands of loyal benefactors across the nation who keep the lights on and the transmitters running. KNOM stands on their shoulders.

[…]Fifty years into KNOM’s history, the radio station is deeply embedded in Western Alaska. As we look to the future, KNOM’s vision is to one day be ‘taken over’ by the region – existing entirely for, and by, Western Alaskans. As the very first song ever played on KNOM – “We’ve Only Just Begun”, by The Carpenters – proclaims, the mission is just getting started.

KNOM continues to live out its values each day – as it has for five decades – as a friend and companion offering respectful service based on Catholic ideals. It is centered on the four cornerstones of the mission: Encountering Christ, Embracing Culture, Empowering Growth, and Engaging the Listener.

KNOM continues in sharing God’s love for Western Alaska through embracing its strength and beauty and being invested, long-term, in the growth of the region.

By engaging each listener with respect and companionship, KNOM hopes to amplify stories of hope, courage, and resiliency in Western Alaska.

Click here for stories and features on the KNOM 50th Anniversary Page.

Saudi Radio To Launch 24-Hour Urdu Transmission (Bol News)

JEDDAH: The Saudi Radio plans to launch test transmission of a 24-hour Urdu service from the middle of September 2021, while the services will be formally launched on September 23, a Saudi official said.

The transmission will include programmes on Islam, the holy Quran, Ahadis and historical and world affairs.

Saudi Broadcasting Authority deputy chairman Faisal Ilyafi said this, while talking to a delegation of the Pakistan Journalists Forum (PJF).

The world transmission was started from the holy city of Makkah in September 1950 with a 15-minute slot for the Urdu programme, he said, and stressed that it is the need of the hour to face challenges and keep ourselves abreast of the changes in media.

The Saudi Urdu transmission has decided to continue its transmission on social media, such as Instagram, Facebook, YouTube, FM, Shortwave, Satellite, and Twitter, he added.

Saudi Crown Prince Mohammed bin Salman has given approval to the project under the supervision of Media Minister Dr Majid bin Abdullah Al Qasabi, he said, adding that the Saudi Information Ministry has also made several other languages part of the project.

The deputy chairman said any language has a supreme significance to disseminate news-cum-events, that’s why many foreign languages such as Russian, Spanish, Japanese, Hebrew and Chinese would be part of the transmission.[…]

Communication Breakdown: Navy Submarines Need a New Way to Talk to Each Other (The National Interest)

As Navy innovators work intensely to pioneer new methods of undersea communication, many might wish to reflect upon the decades of technical challenges associated with bringing any kind of undersea real-time connectivity to submarine operations. Historically, certain kinds of low-frequency radio have enabled limited degrees of slow, more general kinds of communication, yet by and large submarines have had to surface to at least periscope depth to achieve any kind of substantial connectivity.

The advent of new kinds of transport layer communications, coupled with emerging technologies woven into unmanned systems, are beginning to introduce potential new avenues of data processing and transmission intended to bring greater degrees of real-time undersea data transmission to fruition.

Sea water diminishes the power of electrical transmission, challenges identified many years ago by the Navy and some of its partners who have been working on under communication for decades such as Northrop Grumman. Northrop’s efforts date back to the World War II era and, along with the Navy and other industry contributors, helped pioneer the innovations that helped adapt RF communications architecture to sonar today. Considering this history, there are some interesting synergies woven through various elements of undersea warfare radio communications.

A 2014 essay by Carlos Altgelt, titled “The World’s Largest “Radio” Station,” details some of the historic elements of how the U.S. Navy pursued Extremely Low Frequency (ELF) undersea connectivity. Through its discussion of low-frequency ELF connectivity, the essay explains the technical challenges associated with undersea communication, which seem to align with how Northrop Grumman innovators describe how undersea communications will need to largely evolve in the areas of acoustics and optics.

As Altgelt notes: “As a result of the high electrical conductivity of sea water, signals are attenuated rapidly as they propagate downward through it. In effect, sea water ‘hides’ the submarine from detection while simultaneously preventing it from communicating with the outside world through conventional high-frequency radio transmissions. In order to receive these, a submarine must travel at slow speed and be near the surface, unfortunately, both of these situations make a submarine more susceptible to enemy detection.”[…]

North Korean capital cracks down on illegal TVs to prevent access to South Korean broadcasts (RFA via the Southgate ARC)

Each Pyongyang household must report the number of TVs they own, and they face stiff punishments for hiding them

North Korea has ordered residents of the capital Pyongang to report the number of televisions in each household to stop them from watching banned shows from prosperous, democratic South Korea, sources in the country told RFA.

In North Korea, access to media from the outside world is strictly controlled, and TVs and radios are manufactured to only pick up domestic channels and must be registered with the authorities. But residents do find ways to access South Korean signals, either by using foreign televisions or modifying domestic ones.

Getting caught during routine inspections with a TV that can pick up illegal signals is a punishable offense. Residents with more than one television hide their illegal TVs during inspections, only to bring them out again to watch Seoul’s latest hot drama or variety show, former residents told RFA.

Authorities are aware of the deception and have issued a directive that every household in the city declare to their local neighborhood watch unit how many televisions they have.

“Residents are trying to hide them, but the judicial authorities are trying to find them. They are looking for TVs that can get South Korean TV channels in addition to the ‘official’ channels,” said a resident of Pyongyang, who requested anonymity for security reasons.

“Everyone knows that in Pyongyang, South Korean TV signals can be picked up in various areas,” the source said. He mentioned the Mangyongdae and Rangrang districts in the center of the city of 2.8 million.

In these areas the residents have been known to have two or three televisions in their homes, so they can watch the legal channels during inspections and watch South Korean broadcasts in secret,” the source said.

The source said that residents have developed clever ways to hide their illegal TVs.

Read more from this very interesting Radio Free Asia article:
https://www.rfa.org/english/news/korea/tv-05252021155129.html

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A simple guide to portable radio power

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Over on QRPer.com, I just published a post on portable power that was The Spectrum Monitor magazine’s April 2021 cover article.

This article is essentially an overview of a few different types of rechargeable batteries including pros and cons of each chemistry.

While this article focuses on use in ham radio field applications, it also applies to anyone powering receivers–especially those without an internal power supply–in the field.

Click here to read at QRPer.com.

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