Category Archives: Ham Radio

Radio Waves: New Quantum Receiver, Virus and Distance Learning by Radio, BBC Woofferton Early Days, and Hello Morse

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 Andrea, Kim Andrew Elliott, Dave Porter, and Phillip Novak for the following tips:

New quantum receiver the first to detect entire radio frequency spectrum (Phys.org)

A new quantum sensor can analyze the full spectrum of radio frequency and real-world signals, unleashing new potentials for soldier communications, spectrum awareness and electronic warfare.

Army researchers built the quantum sensor, which can sample the radio-frequency spectrum—from zero frequency up to 20 GHz—and detect AM and FM radio, Bluetooth, Wi-Fi and other communication signals.

The Rydberg sensor uses laser beams to create highly-excited Rydberg atoms directly above a microwave circuit, to boost and hone in on the portion of the spectrum being measured. The Rydberg atoms are sensitive to the circuit’s voltage, enabling the device to be used as a sensitive probe for the wide range of signals in the RF spectrum.

“All previous demonstrations of Rydberg atomic sensors have only been able to sense small and specific regions of the RF spectrum, but our sensor now operates continuously over a wide frequency range for the first time,” said Dr. Kevin Cox, a researcher at the U.S. Army Combat Capabilities Development Command, now known as DEVCOM, Army Research Laboratory. “This is a really important step toward proving that quantum sensors can provide a new, and dominant, set of capabilities for our Soldiers, who are operating in an increasingly complex electro-magnetic battlespace.”

The Rydberg spectrum analyzer has the potential to surpass fundamental limitations of traditional electronics in sensitivity, bandwidth and frequency range. Because of this, the lab’s Rydberg spectrum analyzer and other quantum sensors have the potential to unlock a new frontier of Army sensors for spectrum awareness, electronic warfare, sensing and communications—part of the Army’s modernization strategy.

“Devices that are based on quantum constituents are one of the Army’s top priorities to enable technical surprise in the competitive future battlespace,” said Army researcher Dr. David Meyer. “Quantum sensors in general, including the one demonstrated here, offer unparalleled sensitivity and accuracy to detect a wide range of mission-critical signals.”

The peer-reviewed journal Physical Review Applied published the researchers’ findings, Waveguide-coupled Rydberg spectrum analyzer from 0 to 20 GigaHerz, co-authored by Army researchers Drs. David Meyer, Paul Kunz, and Kevin Cox[…]

Virus and distance learning by radio (1937, 1946) (AE5X Blog)

Six to eight decades ago polio was one of the most feared diseases in the US. In 1952 alone, 60,000 children were infected, 3000 died and many more were paralyzed.
The most severe outbreaks were in 1937 and 1946. My father was a victim of the 1946 epidemic, suffering minor paralysis in one leg as a child.

In 1937, many schools around the country closed, as did public pools, movie theaters and parks. But the Chicago public school system took an innovative approach.

During that period, 80% of US households contained a radio. This allowed 325,000 children in grades 3-8 to continue their education at home via radio lessons aired by six Chicago radio stations (WENR, WLS, WIND, WJJD, WCFL, WGN) that donated time for the purpose.

Program schedules for each day were printed in the morning paper. Home with more than one radio & more than one child often set up radios in different rooms so that each child could hear the appropriate grade’s lesson.

This continued for one month…until schools reopened in late September of that year.

Curriculum was developed by teachers and monitored over the air by school officials. After each episode, a limited number of teachers were available for phone calls. A large number of the calls were from parents distressed that they could not clearly receive the broadcasts.[Continue reading…]

BBC Woofferton Early Days (Ludlow Heritage News) [PDF]

Very few structures are left in the Ludlow area which can be traced back to the Second World War. However, look five miles south of the town towards the rise of the hills and a tracery of masts can be seen. Go closer, and a large building can be found by the road to Orleton, surrounded now by a flock of satellite dishes, pointing upwards. The dishes are a sign of the recent past, but the large low building was made for the war-time radio station aimed at Germany.

This little history attempts to tell the story of the British Broadcasting Corporation’s transmitting station at Woofferton near Ludlow in Shropshire during the first years of its existence. When and why did the BBC appear in the Welsh border landscape with a vast array of masts and wires strung up in the air? The story begins in 1932, when the BBC Empire Service opened from the first station at Daventry in Northamptonshire. Originally, the service, to link the Empire by wireless, was intended to be transmitted on long-wave or low frequency. But, following the discovery by radio amateurs that long distance communication was possible by using high frequency or short waves, the plan was changed. Later in the decade, the BBC expanded the service by also broadcasting in foreign languages. Although Daventry had a distinguished name in the broadcasting world, it was never technically the best place for a short-wave site, being on a hill and close to a growing town.

This article can be found in the Ludlow Heritage News: click here to download the full PDF.

Hello Morse: A collection of AI and Chrome experiments inspired by Morse code on Android Gboard (Google)

Developer Tania Finlayson found her voice through Morse code. Now she’s partnering with Google to bring Morse code to Gboard, so others can try it for accessible communication.

Morse code for Gboard includes settings that allow users to customize the keyboard to their unique usage needs. It works in tandem with Android Accessibility features like Switch Access and Point Scan.

This provides access to Gboard’s AI driven predictions and suggestions, as well as an entry point to AI-powered products, like the Google Assistant.[…]

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Listen to a live ARISS contact on Friday, February 2021

Radio Waves: NRAO Turns Scope System Into Planetary Radar, WBCQ Seeks Engineers, Deep Space Network Upgrades, and 2021 Propagation Summit

Radio Waves: Stories Making Waves in the World of Radio

Successful Test Paves Way for New Planetary Radar (NRAO)

The National Science Foundation’s Green Bank Observatory (GBO) and National Radio Astronomy Observatory (NRAO), and Raytheon Intelligence & Space conducted a test in November to prove that a new radio telescope system can capture high-resolution images in near-Earth space.

GBO’s Green Bank Telescope (GBT) in West Virginia — the world’s largest fully steerable radio telescope — was outfitted with a new transmitter developed by Raytheon Intelligence & Space, allowing it to transmit a radar signal into space. The NRAO’s continent-wide Very Long Baseline Array (VLBA) received the reflected signal and produced images of the Apollo 15 moon landing site.

The proof-of-concept test, culminating a two-year effort, paves the way for designing a more powerful transmitter for the telescope. More power will allow enhanced detection and imaging of small objects passing by the Earth, moons orbiting around other planets and other debris in the Solar System.

The technology was developed as part of a cooperative research and development agreement between NRAO, GBO, and Raytheon.

“This project opens a whole new range of capabilities for both NRAO and GBO,” said Tony Beasley, director of the National Radio Astronomy Observatory and vice president for Radio Astronomy at Associated Universities, Inc. (AUI). “We’ve participated before in important radar studies of the Solar System, but turning the GBT into a steerable planetary radar transmitter will greatly expand our ability to pursue intriguing new lines of research.”

Using the information collected with this latest test, the participants will finalize a plan to develop a 500-kilowatt, high-power radar system that can image objects in the Solar System with unprecedented detail and sensitivity. The increased performance also will allow astronomers to use radar signals as far away as the orbits of Uranus and Neptune, increasing our understanding of the Solar System.

“The planned system will be a leap forward in radar science, allowing access to never before seen features of the Solar System from right here on Earth,” said Karen O’Neil, the Green Bank Observatory site director.

“Raytheon’s radar techniques could ultimately improve our ability to explore the Solar System,” said Steven Wilkinson, Principal Engineering Fellow at Raytheon Intelligence & Space. “Working with the astronomy community allows us to apply decades of radar know-how to a project that provides high-resolution images of near-Earth objects.”

“We are excited to be partnering with Raytheon and applying their radar expertise to transform our observatories’ telescopes in new science areas,” said AUI President Adam Cohen.

The National Radio Astronomy Observatory and the Green Bank Observatory are facilities of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.[…]

WBCQ: Radio transmitter engineers wanted

WBCQ Radio is seeking radio transmitter engineers to work at our 500KW shortwave station. Come to northern Maine and get away from it all. Nice working environment, good pay, great people, fun work with BIG transmitting and antenna equipment. Contact Allan and Angela Weiner at 207-538-9180. Please send resumes to [email protected].

Deep Space Network upgrades and new antennas increase vital communication capabilities (NASA)

NASA’s Deep Space Network, commonly referred to as the DSN, has welcomed a new dish, Deep Space Station 56, to its family of powerful ground listening stations around the world.

The now-operational 34-meter antenna joins the network’s Madrid Deep Space Communications Complex located 60 kilometers west of Madrid, Spain while other dishes within the network undergo critical upgrades.

The new dish is part of an ongoing series of enhancements to the DSN, which traces its roots back to January 1958 when the U.S. Army’s Jet Propulsion Lab was tasked with standing up a series of communications stations in Nigeria, Singapore, and the U.S. state of California to support orbital telemetry operations for the Explorer 1 mission.

This precursor to the Deep Space Network was transferred to NASA along with the Jet Propulsion Lab on 3 December 1958. The DSN was then formally commissioned by the U.S. space agency as a way to consolidate the pending deep space communication needs through centralized locations to avoid each mission having to create its own ground listening station(s).

The three Deep Space Network ground locations are spaced roughly 120 degrees from each other in Canberra, Australia; Goldstone, California; and Madrid, Spain. The location of the three facilities ensures deep space missions with a line of sight to Earth can communicate with at least one of the locations at any time.

Updates throughout the decades have increased the network’s capabilities, most notably for the two Voyager probes that continue to operate and send back science data having both long-passed out of the heliosphere and into the interstellar medium.

The network, nonetheless, is showing its age, with upgrades and refurbishments needed to ensure continuous operations. Part of this initiative is the recent addition of the new dish, Deep Space Station 56 (DSS-56), at the Madrid complex.

“After the lengthy process of commissioning, the DSN’s most-capable 34-meter antenna is now talking with our spacecraft,” said Bradford Arnold, DSN project manager at the Jet Propulsion Laboratory.[…]

2021 Propagation Summit Session Recordings Available (ARRL News)

YouTube recordings and PDF files from the 2021 Propagation Summit hosted on January 23 by Contest University are available. More than 1,000 logged in for the sessions. Each presentation begins approximately on the hour. You can advance the video to the presentation you wish to view.

11 AM – “Update on the Personal Space Weather Station Project and HamSCI Activities for 2021” by Dr. Nathaniel Frissell, W2NAF

12 Noon – “Solar Cycle 25 Predictions and Progress” by Carl Luetzelschwab, K9LA

1 PM – “Maximizing Performance of HF Antennas with Irregular Terrain” by Jim Breakall, WA3FET

2 PM – “HF Propagation: What to Expect During the Rising Years of Solar Cycle 25,” by Frank Donovan, W3LPL.

Slides decks are available for each presentation in PDF format: Frissell; Luetzelschwab; Breakall, and Donovan. […]

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How to build a PC keyer and AM modulator for the EMTX emergency transmitter

PC keyer and AM modulator: A 15-components versatile keyer and powerful PSU modulator for the EMTX (Emergency Transmitter)

by Kostas (SV3ORA)

Schematic of the keyer and modulator (on the left) for the EMTX. The EMTX schematic is shown as well on the right, to determine the connections to the keyer/modulator.

Introduction

My very successful emergency transmitter (EMTX) was only capable of CW or other slow speed ON/OFF keying modes. Then I thought, why not “give voice” to the design? CW is good, but it is half of the fun. If you could use your simple CW transmitter to send out your voice as well, this would be great. You could now chat comfortably on the nets or use any digital radio amateur mode and have much more fun. The simplest modulation you can apply to an existing CW transmitter, is the AM modulation. And whereas this is an old modulation, mostly abandoned by HAMs due to beeing inefficient, there are still AM nets on HF. But do not forget, AM can also be heard by SSB receivers by zero-beating the receiver to the AM carrier. So you could still use your simple AM transmitter to QSO with the SSB guys!

Along with the modulator, there is also a versatile keyer embedded to the circuit, so that the EMTX can be manually keyed with different ways or automatically keyed by audio tones from the PC. For more information on the keyer, keep reading.

The AM modulator

In the old days, the most common way to apply AM modulation was to modulate the high voltage to the plate of the tubes, using a transformer and a powerful audio amplifier. In low voltage solid state circuits, you can still do it using transformers, but you can also use series transistors instead of the transformer. All these things require many components and/or powerful AF amplifiers if one is to modulate higher power transmitters. This does not match the keep-it-simple design I am trying to achieve here.

So I thought of a simple trick with the use of the extremely common LM317 regulator, used as a modulated power supply. This modulator uses just a few common cheap components and it is able to achieve remarkably good modulation levels for it’s parts-count, just from line audio input. It juices every bit of the internal circuicity of the LM317, just look at where the base current of the 2N2222 comes from.

The AM modulator is a kind of novelty. Whereas there is nothing special in a modulated power supply, this circuit has some interesting properties. It is amazingly sensitive and it is able to provide lots of modulated current to any low power transmitter that it can feed. It can be easily driven by the line output of any laptop (around 20% volume) and provide a very good depth modulation to the transmitter. Charles Wenzel was kind enough to do a simulation on the circuit I developed, which is shown below.

His simulated circuit is a slight variation (for measurement purposes). The resistor to ground on the base stabilizes the bias and the ratio of R1 and R2 set the output voltage (0.6 volts across R2 gives about 8 volts across R1). He put in an emitter resistor just for good measure. Same for the series resistor from the source. Charles words, “I don’t know how believable these results are but it looks pretty darned good!”.

The circuit is being used as a current booster, the current being the supply to the transmitter and dependent on the voltage it produces. The LM317 always tries to keep 1.25V between it’s output pin and “adj” pin but where we benefit here is the current at the “adj” pin is very low, so it is easier to apply audio to it. Effectively, the error amplifier inside the voltage regulator is used as an additional amplifier stage. The output pin voltage varies according to the voltage on the “adj” pin so if we use it to bias the transistor we get negative feedback which improves the quality of the modulation. More output voltage = more bias current = lower output voltage. The result, is a very cheap, low components-count, very sensitive AM modulator that can supply lots of power to easily drive the transmitter and produce a clean and deep AM modulation!

The AM modulator bias is set with the 1M potentiometer. Depended on the bias level, the idle carrier on the EMTX can be set from about 0.5W all the way up to 8W. Needless to say that this modulator can modulate any similar power transmitter, not just the EMTX.

The keyer

If it is to modulate the EMTX from the PC, so as to use the different digital modes, there must be a way to key it also from the PC. This is why I decided to embed into the same circuit, a PC keyer which is triggered by the line audio of the PC, but also triggered manually (internal or external key). Keying by audio tones was decided, because modern PCs do not have LPT ports to trigger directly by DC. This keyer uses a reed relay to reliably, fastly and scilently key the EMTX, which is activated by a transistor. The base current for the transistor is derived from the audio signal after rectification. The incoming audio from the PC line passes through the mini audio transformer to increase its voltage, it is rectified and then charges the shunt capacitor to drive the base of the transistor. The keyer “speed” (decay) is determined by the shunt capacitor size. The circuit starts to trigger from about 50-60% of my sound card output signal level.

The relay used to key the EMTX, must be able to tolerate at least 1A of switching and carrying current. Note that the relay contacts switching current is not the same as the contacts carrying current. Reed relays are the best especially if you want long relay life, noiseless operation and very fast switching speeds, like the ones used in Hellshreiber. If you can’t find such a relay, you can use a reed switch capable of 1A of switching and carrying current and then place a suitable electromagnet close to it, so you can build the relay yourself. If you do so, find the best point where the reed switch responds to the electromagnet.

The keyer relay must be as close as possible to the emitter of the transistor used in the EMTX. The connectors at the back of the EMTX and the keyer/modulator have been physically placed so that when the two units are side by side, a very short link cable is required for this purpose. With the two devices placed close together, you can now use any length of cable for your manual external key, which is now connected to the “EXT” connector of the keyer/modulator.

The keyer does also have an internal mini straight key. I find this idea very nice, to avoid extra cables. It is not the most convenient key in the world, but it is there along with the transmitter every time you need it. By using a special panel switch from apem, I was able to triple this switch usage for the different modes of the keyer. The vinyl lever cap you see in the next picture, is the original part of the switch, to make it easier to key with your finger. But you may build such a part on your own, to fit on other switches types.

The switch is an ON-OFF-(ON momentary) switch type. In the default (middle) position, only the PC keying action is activated. In the top position (ON), the keyer is always active, which is useful for broadcasting audio (into a dummy load). The bottom (ON momentary) position, is the manual PTT action. This is used as a straight key on OOK operation, or as a PTT on AM voice operation. Simple and effective!

Initially, I used one channel of the PC sound card for triggering the keyer and also as an AF signal for the AM modulator, but this caused several problems of unreliable keying or distortion. So I decided to use a second separate AF input (KAF) to key the keyer. This second input, uses the other channel of the stereo sound card. With the addition of this input, there is no interaction between the keyer and the modulator. The AF levels that the keyer and the modulator require, can be set independently. Instead of adding more hardware for the purpose, I have chosen to set these levels by adjusting the volume and the balance of the sound card, which works great. Also, programs like Fldigi, have options for using one of the two channels of the stereo sound card as a keying interface (PTT channel), which makes the keying efen more reliable. When the program is in transmit mode, a continuous tone is heard on the PTT channel. This steady tone, is used by the keyer as a reliable keying signal, independent of the audio signal of the digital mode that modulates the modulator. This solution works very reliably for any mode. But if the program you are using does not have an option for a PTT channel, that is ok, as the keyer works reliably even without this feature. For voice communication or broadcasting music (into a dummy load) you just use the internal key switch as a PTT to handle these modes.

Results

Prior to building the keyer and the modulator in the same device, I had tested the circuits independently quite a few times, to ensure the results can be reproduced. The modulation quality and depth out of the AM modulator have to be listenned to be believed. I have not made any linearity measurements, I just trust my ears on this one. It works great on music as well as on voice. Apart from that, this is the most sensitive AM modulator I have ever built, requiring only a small fraction of the line level output of the PC sound card.

When modulated by this modulator, the EMTX shows no audible signs of FM modulation. I switched my receiver to SSB and I could perfectly zero beat the AM modulated music signal which stayed on frequency and it’s tone did not change during loud audio signal music. Switching back and forth from SSB to AM modulation on the receiver, I did not notice any difference in the audio quality, apart of course from the narrower bandwidth on SSB modulation, due to the narrower IF filter inside the receiver on SSB.

The AM/OOK switch is used to select the modulation applied to the EMTX. When the keyer is set to be triggered by audio from the PC, at the OOK position, the EMTX is just switched on and off by the audio tones applied to the keyer, or by the manual key, internal or external (connected to the “EXT” connector). At AM position, the EMTX is switched on by the audio signal applied to the KAF connector and at the same time AM modulated by whatever audio signal is applied to the AF connector. On voice communications, the momentary position of the internal key is used as a PTT. On music broadcasting (into a dummy load) the non-momentary position of the internal key is used to keep the keyer always active.

Photos

Back connections to the EMTX.

Pictures of the finished keyer/modulator. You don’t have to build it that nice-looking if you don’t care.

Modulator prototype and EMTX built on a breadboard. Yes it worked just fine onto a piece of wood.

Thank you so much for sharing this brilliant and simple project with us, Kostas. Your handiwork is absolutely brilliant too!

Click here to check out Kostas’ website.

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Radio Waves: Jessica Rosenworcel Acting FCC Chair, Nature Broadcaster Ludwig Koch, India DRM Update, and the QSO Today Ham Expo

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Radio Waves: Stories Making Waves in the World of Radio

Many thanks to SWLing Post contributors Trevor S, Ron, Phillip Smith, for the following tips:

President Biden Taps Commissioner Jessica Rosenworcel as Acting FCC Chair (ARRL News)

President Joseph Biden this week designated FCC Commissioner Jessica Rosenworcel as acting chair of the FCC. She succeeds, at least temporarily, former FCC chair Ajit Pai, who resigned effective on January 20.

“I am honored to be designated as the Acting Chairwoman of the Federal Communications Commission by President Biden,” Rosenworcel said in a statement. “I thank the President for the opportunity to lead an agency with such a vital mission and talented staff. It is a privilege to serve the American people and work on their behalf to expand the reach of communications opportunity in the digital age.”

Prior to joining the FCC, she served as Senior Communications Counsel for the United States Senate Committee on Commerce, Science, and Transportation. Before entering public service, she practiced communications law in Washington, DC.

The newest FCC commissioner, Nathan Simington, a Republican appointee, said Rosenworcel “brings deep knowledge and experience and highly informed judgment to her new position,” and he expressed appreciation that the Biden Administration acted promptly to establish FCC leadership by “selecting such a distinguished public servant for this vital role.

Fellow Democrat Geoffrey Starks said Rosenworcel “has been a passionate advocate for bringing the benefits of broadband to all Americans — particularly our children.” He said her designation as acting chair “comes at a critical juncture for the Commission, as COVID-19 has made bold action to end internet inequality more vital than ever.”

The Commission’s other Democratic appointee, Brendan Carr, called Rosenworcel “a talented and dedicated public servant, as evidenced by her 8 years of distinguished service on the FCC.”

On Twitter, Rosenworcel said, “The future belongs to the connected,” and she described herself as an “impatient optimist, mom, wife, [and] inveterate coffee drinker.”[…]

Ludwig Koch and the Music of Nature (BBC Radio 4)

Ludwig Koch was once as famous as David Attenborough, as pioneering as ‘Blue Planet’ and as important as the BBC Natural History Unit. They all owe their existence to this German refugee who first recorded the music of nature. Through his archive and new field recordings the poet Sean Street tells the story of Ludwig Koch.

When Sean Street was recording in a store-room at the Science Museum for a Radio 4 archive programme he came across a grey crate, stencilled, as if it belonged to a band on tour, with KOCH on it. This was the disc-cutting machine which Ludwig Koch used for a decade to make the recordings of birds, mammals and insects that led to a new field of study, of broadcasting and the creation of the BBC’s Natural History Unit.

Sean and his producer then began investigating and discovered that Koch made the first ever wildlife recording, of a bird, when he was eight, in 1889 – and that it still exists in the BBC’s archives.

Koch was an effusive man and this led to several confrontations with Nazi officials, whom he despised. There is an extraordinary recording of him telling the story of a Berliner whose bullfinch sang ‘The Internationale’. He was carted off to prison and the bird ‘executed’. “Under dictatorship,” Koch observed, “even songbirds suffer”. He came to England, worked with Julian Huxley on theories of animal language, and recorded birds from the Scillies to Shetland.

In 1940 he joined the BBC and soon became a household name, beloved of comedians (there’s a great sketch by Peter Sellers parodying him at work) because of his resolute pronunciation of English as if it were German.

As well as being wonderful radio in itself his work was of great significance. It inspired producer Desmond Hawkins to start ‘The Naturalist’, (using Koch’s enchanting recording of a curlew as its signature tune). Sean Street uses his recordings and contributions of those who worked with him in what becomes a natural history programme in itself, with Koch the subject and Sean exploring his habits and habitat.

There is also an attempt to record curlews as he did so successfully, to shed light on the achievements of this courageous, influential and loveable genius. Today sound-recordists use tiny digital machines and sophisticated microphones. But there are other problems – traffic, planes, people – and fewer, shyer curlews.

Producer: Julian May

Click here to listen to this radio documentary on BBC Radio 4.

Digital Radio Mondiale in Focus in India (Radio World)

The author of this commentary is chair of the Digital Radio Mondiale consortium.

Right from the beginning of 2021, Prasar Bharati, the public radio and TV broadcaster of India, has put its cards on the table. First it clarified that no AIR station was being closed anywhere in any state, a rumor that had made the media rounds in India.

Prasar Bharati has further announced that it is moving ahead with its plans to strengthen All India Radio, expanding its network with more than 100 new FM radio transmitters across India.

The AIR Network already comprises a few hundred stations and several hundred radio transmitters in one of the world’s largest public service broadcasting networks that operates on multiple terrestrial, satellite and internet platforms.

Prasar Bharati is also moving ahead with its plans to introduce digital terrestrial radio in India. According to the Indian broadcaster, select AIR channels are already available through digital DRM technology to listeners in many cities/regions. They can experience the power of DRM through a choice of multiple radio channels available on a single radio frequency in digital mode. These include AIR News 24×7 dedicated to news and current affairs, AIR Raagam 24×7 dedicated to classical music, apart from local/regional radio services and Live Sports.

According to Prasar Bharati AIR is in an advanced stage of testing digital technology options for FM radio, and a standard will be announced soon to herald the rollout of digital FM radio in India.

Already in 2020 AIR had introduced nonstop pure DRM transmissions with three services or programs on one frequency in four key metros: Mumbai 100 kW (1044 kHz), Kolkata 100 kW (1008 kHz), Chennai 20 kW (783 kHz) and New Delhi 20 kW (1368 kHz).[…]

QSO Today Virtual Ham Expo (QSO Today Expo)

Coming to your desktop, laptop, and tablet: March 13 and 14, 2021 and “on-demand” until April 12, 2021

?Early Bird Ticket Sales begin January 4, 2021

?Our first QSO Today Expo was a great success with over 16,000 attendees! We’re working hard to make our upcoming Expo even better with new speakers, panel discussions, kit building workshops, easy-to-use video technology to meet with exhibitors, and much more. There’s no need to travel – anybody can participate in this groundbreaking, amateur radio Expo built on a virtual reality platform.

After our last Expo, we asked for feedback from the amateur radio community on how we could make our next Expo even better. We received great suggestions, many of which we’ve incorporated into our upcoming event. Whether you’re a ham that doesn’t want to travel because of Covid or just live too far from a hamvention, the QSO Today Expo offers the opportunity to learn from many great speakers, meet with exhibitors to see the latest technology, and engage with fellow hams without leaving your home ham shack. And save thousands of dollars since you don’t have to worry about travel, food, and lodging! Early Bird Tickets are just $10 (to help cover the cost of this event, $12.50 at the “door”) and include entry for the Live 2 day period as well as the 30 day on-demand period).

Attendees have the opportunity to:

?Listen to and engage with 60+ internationally recognized ham radio luminaries that have committed to lead Expo sessions. For the list of speakers and speaker topic, click here

Take part in Live virtual kit building workshops. Kits will be available for purchase and delivered to you in time for the Expo so you can participate and build from the convenience of your home.

Walk through our virtual exhibit hall filled with popular amateur radio suppliers. Watch new product demos and interact directly with booth staff. At this Expo we’ll introduce new video technology to enable a better experience when engaging with exhibitors.

Prior to the Expo, take advantage of our new speaker calendar technology to download speaker times in your local time zones to Google and Outlook calendars. This way you’ll have a complete schedule of what sessions you want to participate in.

Return over the next 30 days to listen to speakers you missed during the Live period, explore, and re-engage exhibitor offerings.

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The Icom IC-705 is about to achieve ‘Holy Grail’ status

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In 2019, shortly after Icom announced the Icom IC-705, I speculated that this rig might be a contender for “Holy Grail” status.

I must admit…the more I use this radio, the more I love it. It is a proper Swiss Army Knife of a radio. Even though I’ve owned and operated it for a few months, I still haven’t explored all that it can do, and I keep finding features I love.

Case in point

Yesterday, I upgraded my IC-705’s firmware. Unlike other devices I’ve been evaluating recently, IC-705 firmware updates aren’t fixing numerous bugs and issues, rather they’re adding more functionality.

After completing the upgrade, I hooked the ‘705 up to my main antenna and worked a few Parks On The Air (POTA) stations off of the supplied battery pack (instead of a power supply). While I worked on other projects in the shack, I checked the POTA spots and work a few stations with a whopping 5 watts of output power.

After a couple hours on the air (mostly listening), the internal battery pack still had a good 60-70% capacity.

At one point, I tried a little daytime mediumwave DXing and cruised past 630 kHz which some of you might already know is the home of one of my favorite hometown radio stations, WAIZ.

From my home, WAIZ is a tough catch, so it was weak, but I could hear it.

This reminded me that I had made a recording of WAIZ with the IC-705 when in my hometown earlier this month.

Normally, I pull the MicroSD card out of the IC-705–which almost requires needle nose pliers and is one of my few complaints about this rig–and view the files on my PC or MacBook, but I was curious if perhaps the IC-705 software had a built-in file display.

Of course it does!

Simply press the MENU button, then the RECORD button on the touch screen, and you’ll see the following selections:

Press “Play Files” and you then see a list of folders organized by date:

Click on a folder and you’ll see a list of recordings made that day:

Here’s the genius bit for those of us who like to archive broadcast recordings…the IC-705 embeds the following meta data:

Date of recording
Start time of recording
Recording length
Frequency
Mode

These are some of the most important pieces of information I use to index my audio recordings and the IC-705 does this automatically. In fact, if you allow the IC-705 to gather its time information from the internal GPS, the time stamp will be incredibly accurate.

The only thing I add to the file name after export is the broadcaster name/station callsign.

If that wasn’t enough, if you touch one of the recording files, the IC-705 will open it in an audio player:

The built-in player displays the meta data, and even includes a number of controls like fast-forward, rewind, skip to next or previous file. and pause.

I’m sure this is the same audio player found in the IC-7300, IC-R8600 and other late-model Icom SDR rigs. But in a portable battery powered transceiver? This is a genius feature.

As I type this post I’m listening to the audio from the WAIZ file shown above. I can imagine when I’m able to travel again (post-pandemic), how useful this will for one-bag air travel.

(If you’d like to listen to WAIZ, check out these ‘705 recordings.)

Not only is the IC-705 a QRP transceiver and wideband multi-mode general coverage receiver, but it’s a recorder and audio player with a built-in front-facing speaker. I can set this transceiver at my hotel bedside and listen to recordings I made in the field earlier that day or week.

Keep in mind that the IC-705 is an expensive radio–certainly one of the most pricey QRP radios ever produced at $1,300 US (at time of posting although I’m sure we’ll start seeing lower pricing this year). But if you’re an SWL and ham, you’ll find the IC-705 is the most versatile portable transceiver on the market. If you’re an SWL only, you can disable the transmit on the IC-705 and essentially have a portable battery-powered SDR receiver with built-in audio recording and playback with color touch screen spectrum and waterfall display.

Despite the price, this is Holy Grail territory in my book.

Icom IC-705 Review

If you subscribe to The Spectrum Monitor magazine, you’ll be able to read my (4,000 word!) review of the IC-705 in the upcoming February 2021 issue.

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Icom IC-705 firmware v1.20, programming software v1.10, and a new 3rd party remote app for Android

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Many thanks to SWLing Post contributor, Markku Koskinen, who notes the following new and updated programs for the Icom IC-705 general coverage transceiver:

First, Icom has published firmware version 1.20 which includes a number of new features. We’ll post the full announcement below. Click here to view the release notes and download.

Secondly, Icom has published a new version (1.10) of their IC-705 programming software. The new release also includes a number of additions. Click here to view the release notes and download.

Finally, Markku notes that there is now an IC-705 Remote application on the Google Play app store.

The app appears to control basic functionality like tuning, band, mode, filter, and CI-V address switching. The app is free and should work on most Android devices.

Thanks for the tips, Markku!

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The Icom IC-705 is about to achieve ‘Holy Grail’ status

Case in point

Icom IC-705 Review

Icom IC-705 firmware v1.20, programming software v1.10, and a new 3rd party remote app for Android