Category Archives: Radio History

AM Radio History: 80th Anniversary of the “Havana Treaty,”

Many thanks to SWLing Post contributor, Bob Colegrove, who writes:

Hi Thomas,

I came across this article on Wikipedia. It is a few days late, but thought it might be of interest to others. The link is

https://en.wikipedia.org/wiki/North_American_Regional_Broadcasting_Agreement.

Briefly, this past Monday, was the 80th anniversary of the implementation of the “Havana Treaty,” which was actually signed on December 13, 1937, and finally implemented 80 years ago on March 29, 1941. It provided for reorganization of the “AM” medium wave band into frequency allocations for clear channel, regional and local stations.

AM radio was the Internet of its day. The invention of the telegraph notwithstanding, radio provided widespread, instant communication, albeit one way, to a vast population reaching hundreds of miles from the transmission source. It extended to the most rural parts of the country adding “A battery” and “B battery” to the lexicon.

The initial licensing process had been done with very little planning and forethought using 96 channels between 550 and 1500 kHz. The reorganization was the culmination of the need for some order to reduce mutual station interference and provide more reliable service to listeners. It involved frequency changes for about 1000 stations in several countries. March 29, 1941 was informally known as “moving day.”

The Wikipedia article details the changes made at that time and goes on to describe subsequent expansions of the AM broadcast band.

Fascinating! Thank you for sharing this bit of radio history with us, Bob!

Spread the radio love

1933 Aluminum disc recordings from a DXer in England

Many thanks to SWLing Post contributor, Mark (AE2EA) with the AWA, who writes:

Your loyal followers might be interested in this video of airchecks
recorded on aluminum discs in England of US broadcast stations in late
1933, from the Antique Wireless Museum.

From the AWA description:

These audio clips were recorded on aluminum discs using more of an embossing than cutting action. Reading an AWA Facebook post that the AWA doesn’t have the equipment or experience to digitize the very fragile audio information on these discs, radiodave78@aol.com volunteered to do so. He did a great job is highly recommended for your consideration as a service for archival digitization and restoration.

The discs were in Peter R. Testan’s collection because they included recordings of station WBBC in Brooklyn, NY that his dad, Peter J, started. As well as being a broadcast owner and engineer, Peter J. Testan was also a ham operator. Pictures of his ham shack were featured in a recent issue of the AWA Journal.

While the calls are identifiable, the other programming in these recordings is difficult to listen to. The Creative Director of a New York City radio station remarked after listening: “”It’s so funny because I have DXers sending me EXACTLY the same quality audio as on these discs. Nothing has changed in nearly 100 years!!!”

The audio quality in this video has been enhanced from the original aluminum disc recordings through the use of bandpass filtering, noise reduction and compression, with the goal of removing some of the artifacts of the recording process.

The Wikipedia entry for aluminum discs is pretty succinct: https://en.wikipedia.org/wiki/Aluminum_disc

If you enjoyed this video, consider becoming a member of the Antique Wireless Association at https://antiquewireless.org/homepage/membership/

Absolutely mazing! Thank you so much for sharing this, Mark!

Spread the radio love

1940: When Sears Roebuck sold a wide array of radio gear

Many thanks to SWLing Post contributor, Charlie (W4MEC), who shares a PDF of the 1940 Sears Roebuck Co. catalog section featuring a wide array of radio gear and test equipment.

This file is hosted on the Pro Audio Design forum and can be downloaded as a PDF (15.8 MB) by clicking here.

It’s a real nostalgia trip reading through the fine Hallicrafters, Hammarlund and National HRO descriptions. Thanks so much for sharing this, Charlie!

Spread the radio love

“How To Make a Cheap Receiving Outfit”

Our friends over at the SolderSmoke Daily News recently posted this fun piece from a January 1921 issue of Radio News:

This is great! I’ve often thought a proper ground needed daily watering. And we know it must work: Mars is some serious DX!  Professor Nutty T. Wyrlus was way ahead of his time.

Click here to check out the original post at the SolderSmoke Daily News.

Spread the radio love

Radio Waves: WLW at 100, WWVB Upgrades, Ofcom Radio Amateur Data, and Unlocking the Airwaves

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 Mike Terry, Dave Zantow, and John Figliozzi  for the following tips:


WLW-AM Begins 100th Year On Air (WVXU)

It wasn’t Cincinnati’s first radio station, but WLW-AM is still the biggest.

Cincinnati industrialist Powel Crosley, Jr. began broadcasting WLW-AM over a 20-watt station from his College Hill home on March 2, 1922 – which means that the station is entering its 100th year today.

WLW-AM wasn’t Cincinnati’s first commercial radio station, but it is the oldest surviving station from the 1920s. WMH was operated by the Precision Instrument Co. from Dec. 30, 1921, to January 1923.  WMH was sold to Crosley and merged into WLW, says Randy Michaels, the former WLW-AM programmer and Jacor/Clear Channel executive who is the best radio historian I know.

In 1934, WLW-AM became “the Nation’s station” when President Franklin D. Roosevelt flipped a switch in the White House to activate the station’s unprecedented 500,000-watt experimental transmitter under its Tylersville Road tower. WLW-AM broadcast at “super power” around the clock for five years, through 1939, and continued the mega-wattage output midnight-2 a.m. until 1943. For years WLW-AM has boasted that the 50,000-watt signal reaches 38 states. (I’ve heard the station in New Jersey, Maryland, North Carolina, Florida, Georgia, Illinois and Missouri.)

For 99 years, WLW-AM has broadcast some of the most popular personalities in town: Jim Scott, Gary Burbank, Bob Trumpy, Marty Brennaman and Joe Nuxhall, Cris Collinsworth, Jim LaBarbara, Bill Cunningham, Mike McConnell and Dale Sommers. Before them came Ruth Lyons, Bob Braun, Doris Day, Rosemary Clooney, newsman Peter Grant, sportscaster Red Barber and comedian Red Skelton.

Although WLW-AM likes to promote itself as “news radio,” it’s perhaps best known for carrying Reds and most Bengals games, plus University of Cincinnati football and basketball and Xavier basketball.[]

WWVB broadcast system upgrades may include temporary outages (WWV)

The WWVB broadcast system is being upgraded with new equipment to improve the reliability of the signal. In order to install this equipment, beginning on March 9, 2021 the WWVB signal may be operated on a single antenna at approximately 30 kW radiated power for periods up to several days in duration, and may have occasional outages. Periods of reduced power operation lasting longer than 30 minutes will be logged on the WWVB Antenna Configuration and Power web page, and any outage longer than five minutes’ duration will be recorded on the WWVB Outage web page. Upgrades are expected to be complete by March 31, 2021.

Ofcom released age of radio amateurs data (Southgate ARC)

Following a Freedom of Information request about the age of radio amateurs Ofcom said they do not hold Date-of-Birth information for many radio amateurs but released what information they do have

Ofcom say “We do not hold a full breakdown of the age of issued amateur radio licensees as date of birth is not a mandatory field for licence applications.”

In September 2000 the then communications regulator (RA) abolished the ban on people under 14-years-old holding a Full amateur licence, since that time a person’s date of birth has served little regulatory purpose.

The data Ofcom released showed they only had Date-of-Birth information for:
7,312 out of 28,845 Foundation licences
4,104 out of 12,127 Intermediate licences
44,944 out of 54,072 Full licences

As of March 1, 2021 there was a total of 95,044 valid UK amateur radio licences.

Download the FoI reply and the available age data at
https://ofcom.org.uk/__data/assets/pdf_file/0022/214915/age-of-amateur-radio-licensees.pdf

You can submit a Freedom of Information request to Ofcom online at
https://www.whatdotheyknow.com/new/ofcom

Unlocking the Airwaves (UMD)

Unlocking the Airwaves: Revitalizing an Early Public and Educational Radio Collection is a comprehensive online collection of early educational public radio content from the National Association of Educational Broadcasters (NAEB). The forerunner of CPB and its arms, NPR and PBS, the NAEB developed and distributed educational radio programs and accompanying print materials to schools and communities across the United States. What’s more, the NAEB lobbied extensively to unlock the airwaves—to access precious frequency space—in order to bring the voices of poet Robert Frost, architect Frank Lloyd Wright, anthropologist Margaret Mead, and conservationist “Ranger Mac,” among many other individuals, into American homes and classrooms.

The NAEB’s history is the dramatic story of idealists who believed in the utopian possibilities of technology for education and social uplift and who faced considerable challenges in pursuit of those goals, including economic depression, world war, and the scarcity of the electromagnetic spectrum. It’s a story that has much to tell us about 20th century American culture, as well as the 21st century’s environment of online educational technology and podcasting that we live in today.

Despite its historic importance and contemporary relevance, most of the NAEB members’ programs were never heard again after their initial brief moments on the air. The archives for the radio programs and their related paper documentation have been split for over 25 years between two institutions: the University of Maryland and the Wisconsin Historical Society. Unlocking the Airwaves reunites the split collections, finally realizing the potential of the collections of the NAEB for exploration and and the broader public.

Click here to explore Unlocking the Airwaves.


Do you enjoy the SWLing Post?

Please consider supporting us via Patreon or our Coffee Fund!

Your support makes articles like this one possible. Thank you!

Spread the radio love

Radio Waves: Digital Audio via Vintage Radio, “10-Minute-ish” Transmitter, Why No Channel 37, and Inventor of the Audio Cassette Dies at Age 94

Image by Jon Tyson

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 Ron, Valdo Karamitrov, Ronald Kenyon, and the Southgate ARC for the following tips:


‘I play digital music through my 1949 radio’ (BBC News)

When we think of technology our imagination usually takes us to images of the future. But for some, technology links us to the past – whether for nostalgia or for personal reasons

Following our recent feature on vintage technology, we asked you to share some of your collections with us – and people from around the world responded..

Rob Seaward, North Yorkshire, UK: 1949 Murphy A146 radio

I have a collection of older technology which I have collected throughout my life – including old cameras, calculators, hi-fis and radios. I had been interested in music from an early age, but it was really when my father purchased a Bang and Olufsen music centre that my interest in not only music, but style and function really took off.

To me, a lower middle-class grammar school kid living in Bradford, I suddenly had access to a world of real style and glamour.

My favourite piece must be the Murphy A146 console radio designed by Gordon Russell in 1949.

Its nickname is the “Batwing” because of the shape of the back panel. The sound is rich, slightly warm and typical of valve equipment. In its day, the radio cost the equivalent of an average monthly wage, it was built to last and the original valves are still working today.

However, as it pre-dates FM it is a little limited. I’ve had it restored and as part of the process we had a Bluetooth adapter installed which means I can now play my favourite digital music through this wonder from the 1940s – which really amazes people.[]

Getting on the Air With a 10-minute-ish Ham Transmitter (Hackaday)

Artificially constrained designs can be among the most challenging projects to build, and the most interesting to consider. The amateur radio world is no stranger to this, with homebrew radio designs that set some sort of line in the sand. Such designs usually end up being delightfully minimalist and deeply instructive of first principles, which is one reason we like them so much.

For a perfect example of this design philosophy, take a look at [VK3YE]’s twist on the classic “10-Minute Transmitter”. (Video, embedded below.)

The design dates back to at least the 1980s, when [G4RAW] laid down the challenge to whip up a working transmitter from junk bin parts and make a contact within 15 minutes — ten for the build and five for working the bands. [VK3YE] used the “oner” — one-transistor — design for his 10-minute transmitter, but invested some additional time into adding a low-pass filter to keep his signal clean, and a power amplifier to boost the output a bit.[]

Why Channel 37 Doesn’t Exist (And What It Has to Do With Aliens) (Vice)

Since the advent of analog TVs, channel 37 has always been static. Here’s why.

A version of this post originally appeared on Tedium, a twice-weekly newsletter that hunts for the end of the long tail.

I’m endlessly fascinated by stories of the quirks that were built into the TV system where the well-laid plans of the system simply fell apart because it was asked to do too many things.

Nearly five years ago, I wrote about one of them, the tale of how radio broadcasters were able to shoehorn an additional FM station into the radio because of the proximity of TV’s channel 6 to the rest of the radio feed.

So when I was informed that there was another oddity kinda like this involving the TV lineups, I decided I had to take a dive in.

It’s a tale that centers around channel 37, which was a giant block of static in most parts of the world during the 20th century.

The reason for that was simple: it couldn’t fend off its scientific competition.

1952

The year that the U.S. Federal Communications Commission opened up the television system to use UHF, or ultra high frequency signals. The practical effect of this addition of bandwidth was that the total number of potential TV stations increased dramatically, from 108 to 2,051, overnight. The first UHF applications were granted on July 11, 1952, according to The History of UHF Television, a site dedicated to the higher-frequency television offerings.

The radio telescope that became a headache for the television industry

Within a 600-mile radius of the city of Danville, Illinois, population 31,246, are numerous major cities—among them Chicago, Detroit, Milwaukee, Atlanta, Minneapolis, Pittsburgh, St. Louis, Toronto, and Washington, DC.

Nearly the entire length of the Mississippi River fits into that radius. If Danville was located just a little farther to the east, the radius would also include Philadelphia and New York City. For all intents and purposes, a 600-mile radius from Eastern Illinois covers basically the entire East Coast except the state of Florida and the Northeast.[]

Dutch inventor of the audio cassette tape dies aged 94 (Southgate ARC)

Lou Ottens, inventor of the cassette tape and a CD pioneer died aged 94 at his home in Duizel in Brabant on Saturday, Dutch media report.

Ottens, who studied to be an engineer, started working for Philips in 1952. Eight years later he became head of the firm’s recently introduced product development department. Within a year he and his team had developed the first portable tape recorder of which over a million were sold. Two years later he revolutionised the old reel-to-reel tape system by inventing the cassette tape.

‘I got annoyed with the clunky, user-unfriendly reel to reel system, it’s that simple’, Ottens said later. The new carrier had to be small enough to fit into his jacket pocket, Ottens decided, and he had a wooden model made to determine the ideal size. In 1963 the first plastic encased cassette tape was presented at an electronics fair carrying the slogan ‘smaller than a pack of cigarettes!’ The tapes were quickly copied by the Japanese but in different formats!

Ottens managed to make a deal with Sony to use the mechanism patented by Philips to introduce a standard cassette which was then rolled out globally. Over 100 billion were sold worldwide. Ottens went on to develop the CD, which again became a Sony-Philips standard and which sold over 200 billion.

In 1986 Ottens retired but he was often asked if he was proud of his inventions, which allowed millions to have access to music. ‘I have no ‘pride dial’’ Ottens said in an interview, stressing that both inventions were team efforts. His biggest regret was that that Sony, not Philips, invented what he considered to be the ideal application for the cassette tape, the Walkman. ‘That still hurts,’ he said. Dubious about the recent revival of the cassette tape Ottens said ‘nothing could beat the sound of a CD.’

Read more at DutchNews.nl
https://www.dutchnews.nl/news/2021/03/dutch-inventor-of-the-audio-cassette-tape-dies-aged-94/?


Do you enjoy the SWLing Post?

Please consider supporting us via Patreon or our Coffee Fund!

Your support makes articles like this one possible. Thank you!

Spread the radio love

Photos from an Antique Wireless Association meeting in 2000

Many thanks to SWLing Post contributor, David, who shares the following random photos he recently inherited and scanned. These were taken at an Antique Wireless Association meeting (AWA) from 2000. Click on images to enlarge:

Thank you for sharing these David!

Spread the radio love