Tag Archives: RTL-SDR

Ivan compares the new RTL-SDR V4 and the Airspy Discovery HF+

Many thanks to SWLing Post contributor, Ivan (NO2CW), who writes:

I ran a test of weak signals RTL-SDR v4 against Airspy HF+ Discovery. Using sdr # and a few gain adjustments particular to each of the receivers. I ran the test at approximately 9 pm local time using the same W6LVP loop antenna from my location near Miami Florida and I was intentionally looking for barely readable weak signals. The RTL-SDR v4 is a great budget SDR receiver!

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Radio Waves: Insomnia-Fueled Pirate, Cold War & High-Tech Tactics for Russia, PL-660 Panadapter, Women-Run Radio in Somalia, and Building an SDR Transceiver

Radio Waves:  Stories Making Waves in the World of Radio

Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!


Meet the 68-year-old ‘bad-boy nerd’ behind this North Side pirate radio station (WBEZ)

If you’re driving through the greater Ravenswood area and tune your radio dial to 87.9 FM, you might just enter a sort of radio twilight zone. On tap? Old timey, crime-thriller radio dramas, complete with sleuthy melodramatic music, damsels in distress and classic radio sound effects – footsteps, doors slamming, the gun going off.

There are no call letters or DJs, just “audio noir” floating out over a two-square-mile sweet spot on Chicago’s North Side.

It’s all broadcast illegally out of a nondescript two-flat on a residential block. There’s a spindly antenna on the roof, visible mainly from the alley, and a 50-watt transmitter in the upstairs apartment. And there’s Bill, a retired computer and audio engineer who’s been operating this illegal station for some 15 years. He asked us not to use his last name for fear of “FCC prison.”

“People on the lakefront up in the high rises can hear it,” said Bill. “And they used to listen at Lane Tech somewhere on an upper floor. So it gets out a little ways, but not that far.”

Bill got into noir not because it’s gripping radio, but rather because it’s not. He has insomnia, and the plot lines from Dragnet and Yours Truly, Johnny Dollar help him fall asleep. [Continue reading and listen to this piece at WBEZ.]

U.S. and Ukrainian Groups Pierce Putin’s Propaganda Bubble (NY Times)

U.S.-backed news outlets and Ukrainian activists use Cold War techniques and high-tech tactics to get news about the war to Russians.

WASHINGTON — Using a mix of high-tech and Cold War tactics, Ukrainian activists and Western institutions have begun to pierce the propaganda bubble in Russia, circulating information about the Ukraine war among Russian citizens to sow doubt about the Kremlin’s accounts.

The efforts come at a particularly urgent moment: Moscow appears to be preparing for a new assault in eastern Ukraine that could prove devastatingly bloody to both sides, while mounting reports of atrocities make plain the brutality of the Kremlin’s tactics.

As Russia presents a sanitized version of the war, Ukrainian activists have been sending messages highlighting government corruption and incompetence in an effort to undermine faith in the Kremlin.

Radio Free Europe/Radio Liberty, a U.S.-funded but independent news organization founded decades ago, is trying to push its broadcasts deeper into Russia. Its Russian-language articles are published on copies of its websites called “mirrors,” which Russian censors seek out in a high-stakes game of whack-a-mole. Audience numbers have surged during the war despite the censorship. Continue reading

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Radio Waves: BBC License Fee Frozen, Battling RFI, Warning to RTL-SDR Users in Ukraine, and WRD Special Broadcast

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!


BBC’s funding system under fire (Marketplace)

In the United Kingdom, you need a license to drive a car, fly a plane, practice medicine and watch TV.

The “TV license” is what Brits call their system for funding their world-famous broadcaster, the BBC. Currently, it costs the equivalent of $216 a year and is compulsory. Anyone in the U.K. caught watching or recording programs broadcast on any television channel or livestreamed on an online platform without a license is likely to be prosecuted.

The BBC — the Beeb, as it’s known — derives around $5 billion a year from this source. That’s 75% of the total revenue it needs to run a vast media empire, comprising 10 national TV channels and 10 national and 40 local radio stations as well as its World Service broadcasts and a global news website.

Full disclosure: The Beeb is a content partner for Marketplace.

But the license fee is under attack. The government just announced that it’s freezing the fee at the current level for two years and not increasing it in line with inflation — a decision that could cost the corporation nearly $400 million. The government has also hinted that it would like to eventually scrap the license fee altogether. [Continue reading at Marketplace…]

RF Interference (Nuts and Volts)

It’s everywhere! It’s everywhere! Fortunately, you can take a bite out of RFI.

RF interference — is it interference to you? Is it interference by you? Possibly both! What does this interference consist of? And how can you tell what type is present? A topic that starts off with so many questions is bound to cover a lot of ground, so let’s get started. Continue reading

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Radio Waves: Is the Titus II Still Alive, Navajo Broadcasters Make History, Portalo Stranah, and R.I.P. Sir Clive Sinclair

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 Dennis Dura, Zarpo, Maxime, and the Southgate ARC for the following tips:


Is the Titus II portable Android tablet shortwave SDR close to release? (RTL-SDR)

The PatronX Titus II SDR is something we’ve been posting about several times since 2016, but in the end it was never released and assumed to be vaporware. However, we found that the website for the Titus II SDR was updated only a few weeks ago, and pricing details have been added advertising $120 and $150 for two versions of the product. But on the new website there is no store, just an email link to contact sales for ordering information. We contacted that email two weeks ago for more information but have not received a reply back yet.

The PantronX Titus II was advertised to be a portable Android tablet based SDR that would feature a 100 kHz – 2 GHz tuning range, and software that focuses on HF digital DRM decoding, as well as DAB on VHF. Computer rendered images show the tablet housed in a portable carry enclosure with two speakers. [Continue reading…]

Two Navajo broadcasters make history announcing D1 college football game in Navajo language (KRQE)

ALBUQUERQUE, N.M. (KRQE) – Two men from the Navajo Nation made history at Saturday’s Rio Grande Rivalry game, with a first-of-its-kind radio broadcast in Albuquerque. For the first time ever, two men from the Navajo Nation announced a D-1 college football game in the Navajo Language.

Continue reading

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Videos: RTL-SDR/YouLoop combo and exploring SDRs

Many thanks to SWLing Post contributor, Rob, who writes:

I recently made another video on the AirSpy YouLoop – this time paired in a configuration that shouldn’t really work. I used it with an RTL-SDR v3 dongle in direct sampling mode, and signals still came in. This was somewhat of a surprise given the RTL-SDR v3 isn’t primarily designed for HF.

It may be interesting to readers of the SWLing blog.

I have also started a 2020 SDR Guide that may also have some relevance. Episode 1 looked at some of the things that are possible using Software Defined Radios, and Episode 2 which was released yesterday was an introduction to accessing over 500 online SDRs through 4 different platforms. I focused mainly on HF, and although I didn’t specifically mention the broadcast bands, gace a demo of each platform (KiwiSDR, WebSDR, SpyServer & SDR Console).

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Radio Waves: WBCN, Reactions to AM Digital, More KPH, and Cereal Box Telescopes

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, Troy Riedel, andGrant Porter for the following tips:


WBCN history reveals revolutionary power in local radio (Boston University News Service)

SOMERVILLE – What started as a midnight to 6 a.m. slot on a failing classical music station, became the voice of a generation in 1970s Boston. Now, more than 50 years after WBCN sparked a “revolutionary new experiment in radio,” the bygone rock station is still making waves.

The 2018 documentary, “WBCN and The American Revolution,” tells the origin story of Boston’s first rock and roll station through a combination of rock hits. Never-before-seen photos, videos and interviews with some of Boston’s most beloved radio hosts, were greeted with cheers at the Somerville Theatre screening Thursday night.

Bill Lichtenstein, who began volunteering with WBCN at 14, directed and produced the film. After crowdfunding and a decade in the making, it has been touring independent theaters and festivals across the U.S. for the last year and a half.

WBCN was grounded in good music. Founded by Ray Riepen, owner of South End music venue The Boston Tea Party, WBCN introduced voices like The Velvet Underground, The Who, Bruce Springsteen and Led Zeppelin to the city, and quickly found a home in Boston’s huge student population. Within three months, the station, run by amateur hosts and young volunteers during classroom breaks, was playing 24 hours per day.[…]


“It Will Make Millions of Receivers Obsolete … This Is Needless” (Radio World)

What people are saying to the FCC about all-digital on the AM band

Radio World is providing an ongoing sampler of comments of what people are telling the FCC about its proposal to allow U.S. stations on the AM band to switch voluntarily to all-digital transmission. Here are more in the series:

Kirk Mazurek told the FCC that he is an avid AM listener who has “invested time and money in equipment towards my hobby as many others have. If this proposal goes through it will make the millions of receivers obsolete requiring the purchase of new equipment. This is needless, there are a lot of people who have vintage radios and a lot of them have been restored. This proposal would make them useless. I urge you not to ratify this proposal.”

Mark Wells raised concern about interference from digital to analog signals on the same channel. “This is especially applicable at night when one is listening to distant stations in out-of-state markets, he wrote. “For example, clear channel stations WBT in Charlotte and KFAB in Omaha are both on both on 1110 kHz. Let’s say one switches to digital, and one does not. As it is they both may fade in and out as the atmosphere does its nightly tricks, but the signals remain mostly useable. But, if one is digital and the other analog would it not ‘blank out’ the analog station?”[…]


Podcast features Coastal Radio Station KPH (DitDit.fm)

There was a time when the airways bristled with Morse Code. There were commercial radio stations all around the world whose business was sending and receiving Morse Code messages to ships at sea. Coast station KPH, located at Point Reyes National Seashore near San Francisco, is one of those stations. Richard Dillman was there in 1997 when KPH sent it’s last message and closed it’s doors. It was the end of the line for the men and women who had spent their careers sending Morse Code to ships at sea. There was nowhere else for them to go…

Two years later, Richard Dillman with a group of volunteers returned to KPH and put it back on the air. Listen as Richard tells us about the future of Maritime Morse Code Coastal Station KPH!


A hydrogen line telescope made from cereal boxes and an RTL-SDR (RTL-SDR.com)

SpaceAustralia.com have recently been hosting a community science project that involves encouraging teams to build backyard radio telescopes that can detect the arms of our Milky Way Galaxy by receiving the Hydrogen line frequency of 1420 MHz.

This can be achieved at home by building a horn antenna out of cardboard and aluminum foil, and a feed from a tin can. Then the Hydrogen line and galactic plane can be detected by using an RTL-SDR, LNA, and software capable of averaging an FFT spectrum over a long period of time.

While most horn antennas are typically made from four walls, one participant, Vanessa Chapman, has shown that even trash can be used to observe the galaxy. Vanessa’s horn antenna is made from multiple cereal boxes lined with aluminum foil and an old tin fuel can. The boxes are held together by some string and propped up by some sticks.

With her cereal box horn antenna combined with an RTL-SDR Blog V3, and an RTL-SDR Blog Wideband LNA, Vanessa was able to use software to average the spectrum over time as the galactic plane passed overhead, revealing the Hydrogen line peak and corresponding doppler shift from the galactic plane.[…]


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Hackaday looks back at the venerable RTL-SDR

Many thanks to SWLing Post contributor, Paul Evans (W4/VP9KF), who shares the following article from Hackaday:

Before swearing my fealty to the Jolly Wrencher, I wrote for several other sites, creating more or less the same sort of content I do now. In fact, the topical overlap was enough that occasionally those articles would get picked up here on Hackaday. One of those articles, which graced the pages of this site a little more than seven years ago, was Getting Started with RTL-SDR. The original linked article has long since disappeared, and the site it was hosted on is now apparently dedicated to Nintendo games, but you can probably get the gist of what it was about from the title alone.

When I wrote that article in 2012, the RTL-SDR project and its community were still in their infancy. It took some real digging to find out which TV tuners based on the Realtek RTL2832U were supported, what adapters you needed to connect more capable antennas, and how to compile all the software necessary to get them listening outside of their advertised frequency range. It wasn’t exactly the most user-friendly experience, and when it was all said and done, you were left largely to your own devices. If you didn’t know how to create your own receivers in GNU Radio, there wasn’t a whole lot you could do other than eavesdrop on hams or tune into local FM broadcasts.

Nearly a decade later, things have changed dramatically. The RTL-SDR hardware and software has itself improved enormously, but perhaps more importantly, the success of the project has kicked off something of a revolution in the software defined radio (SDR) world. Prior to 2012, SDRs were certainly not unobtainable, but they were considerably more expensive. Back then, the most comparable device on the market would have been the FUNcube dongle, a nearly $200 USD receiver that was actually designed for receiving data from CubeSats. Anything cheaper than that was likely to be a kit, and often operated within a narrower range of frequencies.

Today, we would argue that an RTL-SDR receiver is a must-have tool.[…]

Click here to continue reading the full article at the excellent Hackaday blog.

Of course, for all things RTL-SDR and beyond, I highly recommend bookmarking RTL-SDR.com.

The RTL-SDR.com blog also manufactures my favorite flavor of the RTL-SDR dongle along with a nice bundle of antennas. Click here to check it out on Amazon.com (this affiliate link supports the SWLing Post).

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