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Radio Waves: Mazdas Stuck On KUOW, Golden Age of Radio, Russian SW Broadcasts to Arctic, FCC Cleans Up Rules, and Starlink Loses 40 Satellites to Geo Storm

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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!

Much thanks to the many contributors who shared the following items:

You’re listening to KUOW … like it or not: Mysterious glitch has Mazda drivers stuck on public radio (Geekwire)

Drivers of certain vehicles in Seattle and other parts of Western Washington are shouting at their car radios this week. Not because of any particular song or news item that’s being broadcast, but because an apparent technical glitch has caused the radios to be stuck on public radio station KUOW.

The impacted drivers appear to all be owners of Mazda vehicles from between 2014 and 2017. In some cases the in-car infotainment systems have stopped working altogether, derailing the ability to listen to the radio at all or use Bluetooth phone connections, GPS, the rear camera and more.

According to Mazda drivers who spoke with GeekWire, and others in a Reddit thread discussing the dilemma, everyone who has had an issue was listening to KUOW 94.9 in recent weeks when the car systems went haywire.

KUOW sounded unsure of a possible cause; at least one dealership service department blamed 5G; and Mazda told GeekWire in an official. [Continue reading…]

The real reason the 1930s were considered ‘the golden age of radio’ (The Grunge)

While it’s been widely contested who actually invented the first radio (both Italian physicist Gugliemo Marconi and Serbian-American inventor and engineer Nikola Tesla were fighting for the first patent, per PBS), it was Marconi who came out top in 1904, when the U.S. Patent Office officially dubbed him the inventor of the new breakthrough technology. According to APM Reports, in 1920, Americans had their first commercially licensed radio station in Pittsburgh, Pennsylvania: KDKA. That number quickly rose after KDKA broadcast the election that saw Warren G. Harding become the 29th president, and by 1924, 500 stations were available for listening.

By 1930, over “40% of American households owned a radio,” per APM Reports. This became known as “The Golden Age of Radio.” As revealed by PBS, in 1930, 12 million Americans owned radios — growing to a whopping 28 million by the end of the decade.

Access to the radio came at a turbulent time in history. As the Great Depression caused widespread suffering for millions of Americans (via History), the households that could afford a radio saw it as a welcome source of entertainment and news that made them feel connected to the rest of the country. These days, with over 15,445 radio stations available in the U.S., it’s clear the radio still remains relevant, but its impact on society truly began nine decades ago. Let’s take a look at the real reason the 1930s were considered “The Golden Age of Radio.” [Continue reading…]

Russia initiates cross-border radio broadcast in North’s languages (Russian News Agency – TASS)

ST. PETERSBURG, February 7. /TASS/. The International Consortium for the Preservation of Arctic Cultural Heritage, based at the Russian State Hydrometeorology University (RSHU), initiated a cross-border radio broadcast in languages of the North’s indigenous peoples, the university’s representative in Moscow Andrei Bryksenkov told TASS.

An application for the broadcast has been filed with the Arctic Council. “The application must be filed from two countries, and we plan to go along with Norway – with the Sami Radio, which is a part of Norway’s big television and radio concern. <…> The idea has been supported at all levels. As for the cross-border broadcast, we, probably, will begin from the shortwave broadcast, as it covers bigger territories and is less costly,” he said.

At the initial stage, the pilot broadcast will be organized on the territories of Finland, Norway and Russia. The project’s initiators are ready to cooperate with other countries. “One transmitter in Krasnoyarsk may cover 80% of the Russian North. Norway has such a transmitter, which covers the Scandinavian territory. Another two transmitters are on Alaska,” he continued. Later on, the broadcast will be also on middle and long waves, thus one frequency will carry 3-4 channels, he added. One of them will be in Russian and English, and the rest – in languages of the indigenous peoples.

The audience will learn about traditions, skills of the peoples living in the North. The content will fully focus on culture. The countries, participating in the project, will open newsrooms. “We hope the general center, which will coordinate the project, will be at the Arctic Council,” he said.

The International Consortium for the Preservation of Arctic Cultural Heritage includes St. Petersburg’s committee on the Arctic, the Arctic museum and exhibition center in St. Petersburg, the Association of indigenous low-numbered peoples of the North, Siberia and Far East, and others. [Read full article…]

FCC Is ‘Cleaning Up’ Of More Radio Rules. Here Is What Will (And Will Not) Change. (Inside Radio)

The modernization of radio’s regulatory rulebook that began under the prior administration continues at the Federal Communications Commission. It is slated to approve a half dozen changes at the Commission’s February meeting, in what Chair Jessica Rosenworcel says is a “cleaning up” of the broadcast radio rules.

“The Commission’s current rules for full-power and translator radio stations contain a number of provisions that are redundant, outdated, or in conflict with other rules,” said Rosenworcel. She said the proposal would “update and clean up” those provisions “in order to reduce any potential confusion, alleviate unnecessary burdens, and make sure our rules reflect the latest technical requirements.”

The proposed order (MB Docket No. 21-263) would update six rules, while scrap plans to change another. They include –

Eliminate Transmitter Power Limit Rule For AMs.

The draft order says the FCC has tentatively concluded the rule is “outdated and unnecessary” given its current reliance on actual operating antenna input power as the most accurate and effective means of ensuring that AM stations adhere to their authorized power limits. The FCC also agreed with comments filed by the National Association of Broadcasters that said the elimination of the technical restriction will allow AMs of any class to use transmitters of any rated power. That, it says, will benefit all AMs by broadening the market of transmitters, enhancing the secondary market for AM transmitters, and reducing the number of transmitters that need to be disposed of.

Clarify AM Fill-in Area Definition

The FCC is poised to amend the definition of an “AM fill-in area” used when an FM translator simulcasts an AM station. [Continue reading…]

Geomagnetic storm and recently deployed Starlink satellites (SpaceX Blog)

On Thursday, February 3 at 1:13 p.m. EST, Falcon 9 launched 49 Starlink satellites to low Earth orbit from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida. Falcon 9’s second stage deployed the satellites into their intended orbit, with a perigee of approximately 210 kilometers above Earth, and each satellite achieved controlled flight.

SpaceX deploys its satellites into these lower orbits so that in the very rare case any satellite does not pass initial system checkouts it will quickly be deorbited by atmospheric drag. While the low deployment altitude requires more capable satellites at a considerable cost to us, it’s the right thing to do to maintain a sustainable space environment.

Unfortunately, the satellites deployed on Thursday were significantly impacted by a geomagnetic storm on Friday. These storms cause the atmosphere to warm and atmospheric density at our low deployment altitudes to increase. In fact, onboard GPS suggests the escalation speed and severity of the storm caused atmospheric drag to increase up to 50 percent higher than during previous launches. The Starlink team commanded the satellites into a safe-mode where they would fly edge-on (like a sheet of paper) to minimize drag—to effectively “take cover from the storm”—and continued to work closely with the Space Force’s 18th Space Control Squadron and LeoLabs to provide updates on the satellites based on ground radars.

Preliminary analysis show the increased drag at the low altitudes prevented the satellites from leaving safe-mode to begin orbit raising maneuvers, and up to 40 of the satellites will reenter or already have reentered the Earth’s atmosphere. The deorbiting satellites pose zero collision risk with other satellites and by design demise upon atmospheric reentry—meaning no orbital debris is created and no satellite parts hit the ground. This unique situation demonstrates the great lengths the Starlink team has gone to ensure the system is on the leading edge of on-orbit debris mitigation. [Read at SpaceX…]

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Radio Waves: SpaceX Encrypts Falcon 9 After Ham Downloads Data, Postcard From Titanic Op at Auction, History of Sound Art, and WNYC’s Early Recording

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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 Ulis (K3LU), Chris Walter, and Ron James  for the following tips:

SpaceX Encrypts Falcon 9 Telemetry After Amateur Radio Operators Download Data (Extreme Tech)

SpaceX doesn’t operate like a traditional aerospace company. For one, the CEO is usually hamming it up on Twitter during launches and providing details that would usually go in a press release. SpaceX also live streams almost all of its launches, even the prototypes that have an unfortunate tendency to blow up lately. It wasn’t even encrypting the Falcon 9 telemetry feed… until now. Unfortunately, some digging by amateur radio tinkerers seems to have convinced SpaceX to step up its security.

It all started a few weeks ago when several Redditors managed to lock onto the 2232.5 MHz telemetry downlink from a Falcon 9 upper stage. Right away, they were able to pull out a few interesting plaintext snippets from the unencrypted feed. With a little more work, the radio enthusiasts were able to capture some amazing images from the spacecraft’s cameras.

After that discovery was public, other SpaceX fans tried to grab some data from the Starship during its prototype tests. However, SpaceX had chosen to encrypt that data. Even with the right wireless equipment, the decoded signal was just noise. Now, it appears the same thing is happening with the Falcon 9. When attempting to pull data from the most recent Falcon 9 launch, the original signal snoopers discovered it had also been encrypted. A series of tweets from SpaceX engineers suggest the decoding of the telemetry signal was the reason for the change.[…]

Postcard from Titanic’s radio operator is being sold at auction (Stars And Stripes)

BOSTON — A postcard written by the Titanic’s senior radio operator just weeks before the ocean liner sank in the North Atlantic in 1912 has been put up for auction.

The card, with a glossy image of the ill-fated ship on the front, was written by Jack Phillips to his sister, Elsie Phillips, in March 1912 while awaiting the ship’s first sea trials, according to RR Auction in Boston.

“Very busy working late. Hope to leave on Monday & arrive Soton Wednesday afternoon. Hope you quite OK. Heard from Ethel yesterday,” he wrote. It’s signed “Love Jack.”

It is postmarked Belfast, where the Titanic was built, and has a canceled halfpenny stamp.

“Soton” is a contraction of Southampton, the English port city from where the Titanic departed on its maiden voyage. It sank in the early morning hours of April 15.

Phillips, who turned 25 on board, stayed at his post after the Titanic struck an iceberg to send calls for assistance to other ships in the area until water was lapping around his feet, according to RR Auction.

He made it off the ship after being told by the captain that he had done his duty, according to his biography in the British National Archives, but died of exposure in the frigid North Atlantic, according to RR Auction.

The postcard is being sold by the estate of Vera and John Gillespie, longtime members of the Massachusetts-based Titanic Historical Society, said Bobby Livingston, executive vice president at RR Auction.[…]

Radio Survivor Podcast #292: The History of Sound Art (Radio Survivor)

What is sound art? And what do we know about its origin story? We explore this question and more with our guest this week, artist and educator Judy Dunaway. An adjunct professor in the History of Art Department at Massachusetts College of Art and Design, Dunaway’s recent article, “The Forgotten 1979 MoMA Sound Art Exhibition,” is a fascinating look at the history of sound art and highlights important contributions by female artists. In our wide-ranging discussion, we also hear about Dunaway’s own artistic practice, from her work with latex balloons to transmission art to a “phone improv” show over BlogTalkRadio a decade ago.

Click here to check out this piece at Radio Survivor.

 

Overcoming the Limitations of Time (From the January/February 1940 WNYC Masterwork Bulletin)

A MATTER OF RECORD: Mighty useful gadgets are WNYC’s four new recording machines. They were used in a variety of interesting ways during the past year, so we decided that the how and the why of recording would be an appropriate subject for this, the third of our Behind the Microphone series dealing with the technical side of things at the Municipal Station.

One of the most valuable uses of the recording units is that they have partially enabled us to overcome the limitations of time — have made it possible to make available to our listeners important evening programs which we could not broadcast directly because of our fluctuating time allotment.

For instance, we could not pick up the ASCAP Music Festival Concerts from Carnegie Hall last Fall because WNYC was not on the air after 8:30 P. M.[1] What to do? The recorders to the rescue! The concerts were “broadcast” over our regular Carnegie Hall lines to the Municipal Building where they were transcribed on our two standard studio-type recording machines. Each transcription[2] was put on the air on the afternoon following the original perfor

Similarly, our two mobile recording units made possible an afternoon broadcast of the official opening of La Guardia Field which took place at midnight. Recording equipment is also used frequently to transcribe major programs “off the air” so that they may reach a larger audience through rebroadcast. There was the time, for example, when the Mayor’s office was the scene of a final report on the new Police and Fireman’s pension plan. Official reports on the balloting were recorded and rebroadcast at a time when the majority of the policemen and firemen affected could listen in.

We used to think recording an easy job: Just put the recording needle on the disk, turn a few buttons, and let ‘er go. After watching one of our expert recording engineers at work, we realized that it’s a delicate task, requiring special training and long practice.

Click here to read the full piece at WNYC.

 

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Radio Waves: New SiriusXM Satellite, Tour of CHU, Icom ID-52 Delay, and Grant’s Prototype Broadcast Receiver

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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, Tracy Wood, John Palmer, and Greg Jasionek for the following tips:

SpaceX Launches Latest Satellite For SiriusXM Radio (Spaceflight Insider)

On Sunday December 13, a SpaceX Falcon 9 rocket successfully lifted off from SLC-40 at Cape Canaveral Space Force Station in Florida, carrying the SXM-7 satellite to a geostationary transfer orbit. The flight came two days after SpaceX’s first launch attempt on Friday, which was aborted at t-minus 30 seconds. The company tweeted the reason for the scrub, “Standing down from today’s launch attempt to perform additional ground system checkouts.” While SpaceX did not point to a specific reason for the hold call, it can be assumed that either the onboard computers or ground controllers found something off-nominal in the final seconds before liftoff.

[…]The payload, the SXM-7 satellite, is the latest addition to Sirius XM’s constellation of satellites aimed at delivering an extensive library of music and entertainment to most parts of the world. SXM-7, along with its sister satellite SXM-8 launching in 2021, are aiming to replace the company’s aging XM-3 and XM-4 satellites. Contracted and built by Maxar for Sirius XM, the 7,000 Kilogram satellite is based on the SSL-1300 Bus and utilizes a host of S band transponders to provide satellite radio to customers in North America.

“Maxar and SiriusXM have worked together for more than two decades to build world-class digital audio radio satellites that bring entertainment to almost every new car in America,” said Megan Fitzgerald, Maxar’s Senior Vice President of Space Programs Delivery. “We are proud to have built the latest addition to the SiriusXM constellation and look forward to the launch of their next Maxar-built satellite, SXM-8, next year.”[…]

CHU, Canada’s Time Station (Radio World)

Look inside the facility that broadcasts voice time signals in two languages

It is nestled in a farmer’s field in southwestern Ottawa, Canada, in a protected area known as the Greenbelt, surrounded by miles of sprawling suburbia.

It is CHU, Canada’s own automated time station.

Operating from a 1940s-era transmitter building and three vertical antenna towers, CHU broadcasts automated voice time signals in both English and French 24/7.

Its broadcasts are transmitted on 3.33, 7.85 and 14.67 MHz, and are heard through central/eastern Canada and the eastern United States, plus many other areas of the planet on a regular basis.

CHU’s time service is operated by Canada’s National Research Council, with the station being remotely controlled from the NRC’s Montreal Road headquarters central Ottawa some 12 miles away. The time signals are based on CHU’s trio of atomic clocks on-site, which are constantly checked against the atomic clocks at NRC headquarters.

“We are equipped with 1960s-era 10 kW transmitters that have been highly modified over the years,” said Bill Hoger. He is the Research Council officer who maintains the unmanned station as part of his overall duties along with two other off-site technicians.[…]

ID-52 Apology and Notice of Production Delay (Icom)

Thank you for your continued patronage of Icom products.

Regarding the 144 / 430MHz dual band 5W digital transceiver “ID-52” released in October 2020, there is a delay in the supply of parts from external partner companies, and additional production is significantly delayed. We sincerely apologize for the inconvenience caused to customers and retailers who are waiting for ID-52.

We will inform you about the timing of resuming production as soon as it is confirmed.

We are doing our utmost to resume production as soon as possible, and we appreciate your understanding.

New Type of Broadcast Receiver (LinkedIn Post)

There has been a lot of testing over last few month, with the new working prototype AM receiver. It has taking almost two years to get to this point with a lot of testing to find out what works and what does not.

The performance on Long wave and Medium wave is outstanding with the external loop configuration, this has many advantages over a ferrite rod antenna design. The Short wave performance is OK, where the front end RF transformers need to be improved with more testing. It out performs my Tecsun PL-398 that uses Digital Signal Processing (DSP), and comes close to what is possible within the high noise floor that you get in buildup areas.

The adaptive processing works very well, where you can set in software to work based on the signal level and if there is a pilot tone been detected (stereo indicator), this works for both the AM bands and for FM. As with the adaptive processing the noise reduction also works with both AM and FM bands, that has been use with Short wave and Long wave stations. The de-emphasis cave is design for 50 ?s, to pass a wider modulation bandwidth through up to 12.5 kHz.

The Denon TU-680NAB has been the reference receiver throughout all the testing to get to this test point. As this was designed for the high end audio market in the 1990’s, to provide the best possible performance for HiFi systems of the day.

[…]This will be marketed as a high end broadcast receiver, the aim is to stay well clear of low cost products from China, that are all too common these days. This is a Canadian product, showing that there are many new ideas and what possible in this area of development. With all these advancement it possible to provide a high quality music programming using AM radio that sounds as good as FM, with the advantages of larger coverage areas.[…]

Click here to read the full post with specifications.

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Radio Waves: ATC Communications, ABC is Highly Trusted, New SW Forum in Turkey, and Did a Ham Speak To Crew Dragon?

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Photo credits: NASA/Bill Ingalls

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 Michael Bird, Seyfi Genç, and London Shortwave for the following tips:

Can you hear me now: How pilots communicate with ATC while 35,000 feet in the air (The Points Guy UK)

When you’re in a sealed, pressurised tube five miles above the ground, being able to communicate effectively is essential. In the early days of aviation, flags and light signals were used before designers were able to fit basic radio equipment into aircraft.

Modern aircraft now have an array of communication devices from the rudimentary HF radios of old to sophisticated satellite-based systems that enable us to talk almost as if we were on a mobile phone.

[…]The most common form of communication in aviation, very high frequency (VHF) radio calls are what we use for around 95% of our communications with ATC. In simplified terms, the transmitting station sends a signal that travels in a straight line and is picked up by the receiving station.

VHF comms provide clear voice communications. However, as the radio signals travel in straight lines, they are limited by the curvature of the earth and objects that they may come into contact with, such as hills and mountains.

The distance which a VHF signal can travel depends on both the height from which the signal is sent and the height of the receiving station. If both the sender and the receiver are on the ground, the distance will be relatively small. If both stations are in the air, the distance the signals can travel is much further.[…]

Bushfire Research shows ABC Radio highly trusted and saves lives (Radio Info)

As the Bushfire Royal Commission continues, the ABC has released independent research that shows Australians turned to the national broadcaster in record numbers during the recent bushfire crisis.

The research shows that the ABC was the most trusted information source during the fires and that lives were saved as a result of people acting on information the ABC provided.

At the height of the bushfire crisis (31 December-14 January) ABC Sydney and ABC NSW local radio produced 296 hours of rolling/continuous fire coverage, ABC Gippsland 134 hours, and ABC Melbourne 83 hours.[…]

New Shortwave Forum in Turkey

73 and hello from Shortwave Forum!

A dedicated Facebook and parallel Whatsapp group, to exchange news and info by SWL’s and DX’ers from Turkey, NOW goes wider and more permanent:

http://www.shortwaveforum.com

The Shortwave Forum will be open to all who want to join and contribute. Membership is free.

With members from all corners of the globe, the content of our beautiful hobby will reach the richness it always deserves.

Register now! And keep those tips and news coming!

Did a Ham Radio Enthusiast Actually Speak to Crew Dragon? (Popular Mechanics)

In a strange turn of events, a ham radio enthusiast in Gujarat, India falsely claimed to have made contact with NASA astronauts Bob Behnken and Doug Hurley during their historic journey to the International Space Station last weekend.

Engineer Adhir Saiyadh told the Ahmedabad Mirror he decided to try to connect with the ISS as it sped over India and “coincidentally got connected to their frequency and received a response from one of the commandants of the capsule,” he said.

But NASA says it simply isn’t true.

Behnken and Hurley blasted off from NASA’s historic Launch Complex 39A on Saturday, May 30. After 19 hours in orbit, the astronauts docked with the ISS and reunited with fellow astronaut Chris Cassidy—whose ham call sign is KF5KDR, by the way—and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner.

“We did check with SpaceX to confirm that they were not aware of any communication with the astronauts via ham radio, and the crew did not report having received communication,” a NASA spokesperson told Popular Mechanics via email. “We are also under the impression that may be technically impossible for the Crew Dragon to communicate through ham radio.”[…]

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Quindar Tones: Those iconic NASA PTT confirmation beeps

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Photo credits: NASA/Bill Ingalls

Yesterday, my family watched the successful launch of the NASA Demo-2 SpaceX Dragon via YouTube.

As astronauts Robert Behnken and Douglas Hurley communicated with Mission Control, we heard PTT confirmation beeps after each transmission.

Those beeps, of course, reminded me of past NASA missions and those iconic confirmation tones we heard in audio from the Mercury, Gemini, and Apollo days all the way into Space Shuttle missions.

Quindar Tones

Source: honeysucklecreek.net

Last year, after spending a couple of days at the US Space and Rocket Center (and attending the Huntsville Hamfest), I heard numerous NASA audio clips and that lead me down the path of researching those PTT confirmation tones.

Turns out, they’re called “Quindar Tones.”

I couldn’t find any information about Quindar Tones at the US Space and Rocket Center–although, admittedly, the place is massive and I could have easily overlooked it–so I did a little research when I returned home.

I found this archived post on the NASA’s Apollo Lunar Surface Journal wesbite:

Re: Apollo beeps

Journal Contributor Mark Burckhard writes:

“I’ve always wondered what purpose the ‘beeps’ served that one heard intermittently during the voice communications with the Command and Lunar Modules during the Apollo missions, as well as other space missions.”

Journal Contributor Mike Dinn provides an MP3 clip ( 123k ) from a network audio check that includes numerous quindar tones.

Journal Contributor Markus Mehring replies:

“‘Other space missions’ is quite an accurate observation, since the ‘beeps’, in fact, are still in use today on Shuttle flights, at least on the UHF frequencies.”

“These beeps are called ‘Quindar-Tones’. Their purpose is to trigger the ground station transmitters when there is an outgoing transmission from Earth. The CapCom in the Mission Control Center, who is taking care of communications with the crew, uses his communication gear in a PTT mode exclusively. ‘PTT’ is short for Push-To-Talk, which means that the CapCom presses a button every time and as long as he wants to talk. (The crews back during Apollo – and also today – usually communicate via PTT as well, but they also have the so-called ‘VOX mode’ at their disposal, in which their microphones are voice-triggered by a certain adjustable threshold volume levels. VOX is used when they don’t necessarily have their hands free.)

When the CapCom presses his PTT button to start a transmission, an intro tone (2.525KHz sine wave with a length of 250ms) is generated and triggers the ground station transmitters to send. And when he is finished talking and releases the button again, a slightly lower outro tone (2.475KHz, sine, 250ms) is generated to trigger the ground station transmitters to turn off. So in short, these are remote control trigger tones.

CU! Markus”

I then discovered this article via the Internet Archive Wayback Machine, which gave more detail about the Quindar Tones’ name and some of the idiosyncrasies of the system:

The story behind the “Beep”

Steve Schindler, an engineer with voice systems engineering at NASA’s Kennedy Space Center, offers the following history of [Quindar Tones] origins.

“Quindar tones, named after the manufacturer of the tone generation and detection equipment, are actually used to turn on and off, or “key,” the remote transmitters at the various tracking stations (Merritt Island Launch Area–now Kennedy Space Center, Bermuda, Australia, etc.) that were used to communicate with the Mercury through Apollo spacecraft and, in some cases, are still used with the Space Shuttle.”

[…]”Although it usually worked well, there were a couple of peculiarities with this system. If the transmitter was keyed and the telephone line connection broken, the transmitter would never get the tone to turn off. To prevent this there was a “transmitter on” light at each remote site that would come on when the transmitter was keyed. Someone was supposed to monitor the circuit and if the audio dropped, but the “transmitter on” light was still on, they would have to manually unkey the transmitter. Also, just before communications was handed over to a new tracking station, the key-unkey tone pair was sent 10 times to ensure that everything was functioning correctly. This was done before the audio was patched to the tracking station’s line so it wasn’t heard in the control room or on NASA Select audio.

The Quindar system was actually built from a piece of equipment that was used to put multiple teletype circuits on a single phone line by means of frequency domain multiplexing. Because replacement parts are no longer available, an “out-of-band signaling” system was installed in 1998 for the transmitters located in the U.S. This system uses a continuous tone that is below the normal audio frequency range. When the tone is present, the transmitters are keyed. When the tone is not present, the transmitters are unkeyed. It worked fine, but the Astronaut Office complained about the lack of tones which everyone had become accustomed to as an alert that a transmission was about to start. So, the Quindar tone generator, which was still installed in case it was necessary to key the transmitters at an overseas site, was re-enabled.

Even though you won’t hear the same Quindar tones in present-day space missions, you can listen until your heart is content at the website Apollo In Real Time.

The Internet Archive also has a massive collection of Apollo audio free to stream and download.

Quindar Music

If you’re fascinated with the NASA audio soundscape in general, you might check out the electronic music duo Quindar featuring longtime Wilco member Mikael Jorgensen, and art historian-curator James Merle Thomas.

Quindar: Mikael Jorgensen & James Merle Thomas. Photo by Chad Ress, Spacesuits by Cassandra C. Jones

Science Friday featured an extended interview with the group in 2017. If you love electronic music–especially if you’re a fan of Wilco, it’s well worth a listen:

Check out their latest video, Choco Hilton:

Speaking of Mikael Jorgensen and Wilco, I should note here that their album yankee hotel foxtrot has a deep shortwave motif.

Anyone else fascinated with Quindar Tones and NASA audio? Feel free to comment and share any other resources or projects you’ve found.

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SpaceX’s Falcon 9 payload includes the HawkEye 360 radio-wave emission seeker

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Many thanks to SWLing Post contributor, Balázs Kovács, who shares the following:

Hi Thomas,

Just found: the launch of the SpaceX’s Falcon 9 rocket was delayed today, part of the load is a new radio-wave emission seeker satellite system the Pathfinder from HawkEye 360:
https://www.businessinsider.com/spacex-to-launch-70-satellites-radio-tracking-2018-11

Some parts from the article:

“An unprecedented rocket mission for SpaceX, called SSO-A, will launch 71 small satellites at once on Monday. Three of the satellites belong to HawkEye 360, a startup that aims to “see” radio-wave emissions all over Earth. HawkEye 360’s software will identify each unique radio signal and use it to track “dark ships” that may be trying to hide illegal activities.”

[..] The antennas of Pathfinder can detect a wide range of radio signals above about 1 watt in power. [..] This means the cluster can triangulate normally hard-to-pinpoint signals from satellite phones, push-to-talk radios, and marine radar. [..] In the future, they aim to launch five more three-satellite clusters, which will create a constellation that can map Earth’s radio signals once every 30 to 40 minutes. [..] Another planned use of Pathfinder is more down-to-earth: The technology could detect improper use of the radio-frequency spectrum, including interference between cell-phone towers.”

Thank you for the tip, Balázs!

I also discovered the following short video which introduces and describes the system:

Click here to view on YouTube.

Sounds like an amazing system although it certainly does feel a little “big brother”–!

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