The Silent Siege: Defending the Radio Spectrum in an Age of Noise

3,286 words, 17 minutes read time.

The electromagnetic spectrum is currently facing an unprecedented siege from commercial expansion, environmental noise pollution, and regulatory encroachment, threatening the viability of independent communication. This conflict involves a diverse cast of actors ranging from multinational telecommunications conglomerates and unsuspecting homeowners to a dedicated community of radio operators who stand as the last line of defense for this invisible public resource. While the general public remains largely unaware of the radio waves passing through them, a fierce battle is being waged for control of these frequencies, occurring in corporate boardrooms, legislative chambers, and the backyards of suburban neighborhoods. The stakes are considerably higher than mere hobbyist chatter; at risk is the ability to maintain decentralized, resilient communication infrastructures independent of the fragile commercial grid. As the demand for wireless data explodes and the noise floor rises, the preservation of the spectrum requires a concerted response from informed men willing to understand the physics, the policy, and the practical application of radio technology.

The Commercial Encroachment on Finite Resources

The most immediate and powerful threat to the radio spectrum comes from the insatiable commercial appetite for bandwidth. As modern society transitions into an era defined by the Internet of Things and 5G connectivity, corporate entities are aggressively lobbying for access to every available slice of the radio frequency pie. This creates a direct conflict with existing services, including the bands historically allocated for amateur and emergency use. The spectrum is a finite physical resource; unlike fiber optic cables where more strands can be laid, there is only one electromagnetic spectrum. When a frequency band is auctioned off to the highest bidder for billions of dollars, it is often lost to the public domain forever. This commoditization of the airwaves treats a law of nature as a piece of real estate to be fenced off and monetized.

The pressure is particularly intense because the specific frequencies that are most desirable for long-range communication or high-penetration data signals are the very same frequencies that have been cultivated by amateur operators for decades. Telecommunications giants view these bands as underutilized assets waiting to be exploited for profit. The concept of “use it or lose it” has never been more relevant. If a community of capable operators does not actively occupy and defend these frequencies through demonstrated utility and public service, regulators face immense pressure to reallocate them to commercial interests. This reality turns every licensed operator into a stakeholder in a global resource management crisis. The defense against this encroachment is not just about complaining to regulators; it involves demonstrating the unique value of non-commercial spectrum access, particularly its role in disaster recovery when profit-driven networks fail.

The Rising Tide of the Noise Floor

While commercial reallocation attempts to steal the spectrum from above, a more insidious threat is rising from below: Radio Frequency Interference (RFI). This phenomenon is often referred to as the rising “noise floor.” In the past, turning on a radio receiver resulted in a quiet hiss of static, out of which a voice or signal would clearly emerge. Today, that quiet background is increasingly replaced by an angry roar of electronic smog. This pollution is generated by millions of poorly shielded consumer electronic devices. LED light bulbs, variable speed pool pumps, cheap switching power supplies, and solar panel inverters spew stray radio frequency energy into the environment. To a casual observer, these devices are harmless conveniences; to a radio operator, they are jammers that blind receivers and render communication impossible.

This environmental degradation of the electromagnetic spectrum creates a scenario where even if the frequencies are legally protected, they become practically useless. It is akin to owning a plot of land that has been flooded by toxic waste; you may hold the deed, but you cannot build on it. The physics of radio reception rely on the signal-to-noise ratio. As the noise floor rises, stronger and stronger signals are required to break through, effectively shrinking the range of communication systems. A handheld radio that could once talk to a station thirty miles away might now struggle to reach three miles across a noisy city. This threat is largely unregulated at the consumer level, as the enforcement of interference standards has lagged behind the proliferation of cheap electronics imported from manufacturers who cut corners on shielding.

Community Response and Technical Stewardship

The response to these threats has catalyzed a sophisticated movement within the radio community focused on stewardship and technical innovation. This is not a passive group; it consists of technically minded individuals who view the spectrum as a public trust. The primary weapon in this response is education and technical adaptation. Operators are developing new digital transmission modes designed specifically to function in high-noise environments. These modes use advanced signal processing and error correction to decode messages that are buried deep beneath the electronic smog, effectively reclaiming territory that was thought to be lost. This demonstrates a resilience and ingenuity that defines the spirit of the radio community. Rather than surrendering to the noise, they engineer their way through it.

Furthermore, the community response involves active monitoring and “fox hunting”—the practice of locating sources of interference. When a rogue signal or a malfunctioning device disrupts communications, operators use directional antennas and triangulation techniques to physically track down the source. This can lead to diplomatic engagements with utility companies to fix arcing power lines or helping a neighbor replace a noisy power supply. It is a form of neighborhood watch, but for the electromagnetic environment. This hands-on approach requires a deep understanding of wave propagation and electronics, skills that are honed through the pursuit of licensure and regular practice. It reinforces the idea that the spectrum is a shared backyard, and it is the responsibility of the residents to keep it clean.

The Regulatory Battlefield and Property Rights

Beyond the technical challenges, a significant battle is being fought on the regulatory front involving Homeowners Associations (HOAs) and private land covenants. These restrictions often prohibit the installation of external antennas, effectively locking millions of potential operators out of the spectrum. The “CC&Rs” (Covenants, Conditions, and Restrictions) that govern many modern housing developments prioritize aesthetic uniformity over functional resilience. This creates a paradox where a resident may legally hold a federal license to operate a radio station for emergency communications but is contractually banned from erecting the antenna necessary to use it. This represents a clash between private contract law and the public interest in maintaining a dispersed, capable civil defense network.

The community response to this has been a mix of legislative lobbying and stealth engineering. Legislation like the Amateur Radio Parity Act has been introduced in various forms to try and force a compromise, arguing that reasonable accommodation for antennas is a matter of national safety. On the ground, operators have become masters of stealth, deploying “invisible” antennas disguised as flagpoles, hidden in attics, or woven into landscaping. This ingenuity allows men to remain active and capable despite the restrictions, maintaining their readiness and their connection to the airwaves. It is a quiet act of rebellion, asserting the right to communicate and the duty to be prepared, regardless of arbitrary rules set by a housing board.

Strategic Implications of Spectrum Dominance

The importance of this subject extends into the realm of national security and strategic independence. In an era of cyber warfare and potential infrastructure attacks, reliance on centralized communication networks—like cell towers and the internet—is a vulnerability. These systems are fragile; they depend on the power grid, fiber backbones, and complex software stacks that can be hacked or jammed. The radio spectrum, accessed through decentralized amateur equipment, offers a fallback layer that is robust because of its simplicity and distribution. There is no central switch to turn off the ionosphere. There is no server farm to bomb that will silence point-to-point radio communication.

Understanding the spectrum allows an individual to step outside the “matrix” of commercial dependency. When the cellular networks are congested during a crisis, or when internet service providers suffer outages, the radio operator remains connected. This capability is not just about personal safety; it is a community asset. The response to spectrum threats is fundamentally about preserving this capability for the greater good. It aligns with a masculine ethos of protection and provision—ensuring that when the primary systems fail, a secondary, hardened system is ready to take over. This requires a workforce of licensed operators who are not just hobbyists, but disciplined communicators who understand the strategic value of the frequencies they guard.

Historical Context of Spectrum Allocation

To fully appreciate the current threats, one must understand the history of how the spectrum was tamed. In the early days of radio, the airwaves were a chaotic frontier, much like the Wild West. There were no lanes, no rules, and constant interference. The catalyst for order was the sinking of the Titanic in 1912. The tragedy highlighted the deadly consequences of unregulated communication, where distress calls could be missed or jammed by irrelevant chatter. This led to the Radio Act of 1912, which established the principle that the spectrum is a public resource to be managed by the government for the public good. It established the licensing structure that exists today, creating a hierarchy of users and prioritizing safety of life.

Over the last century, this allocation has evolved into a complex map of frequency blocks assigned to military, aviation, maritime, commercial, and amateur users. The amateur allocation was not a gift; it was carved out by pioneers who proved that the “useless” shortwave frequencies could actually span the globe. Today’s operators are the inheritors of that legacy. They occupy the bands that their predecessors explored and charted. The threat of losing these bands is a threat to erase that history and the public’s right to access the airwaves directly. The historical perspective reinforces why the community is so defensive of its privileges; they know that once a frequency is surrendered to commercial interests, it is never returned.

The Human Element of the Network

Technology and policy are critical, but the most vital component of spectrum defense is the human operator. A radio is merely a collection of capacitors and transistors until it is powered by a human intent on communicating. The decline in the number of active, knowledgeable operators is perhaps the greatest threat of all. A spectrum that is silent is a spectrum that is vulnerable to reallocation. The community needs fresh blood—men who are willing to learn the code, understand the electronics, and join the network. This is not about nostalgia for old technology; it is about maintaining a vital skill set in the modern world.

The culture of the radio community is one of mentorship and rigor. It welcomes those who are willing to put in the work to understand the medium. When a man decides to study the spectrum, he is not just preparing for a test; he is learning the language of the universe. He learns how the sun’s cycles affect communication, how the terrain shapes a signal, and how to build systems that survive when others fail. This human element is the ultimate check against the threats of noise and encroachment. An educated, active populace is the strongest argument for the continued preservation of the amateur bands.

Technological Adaptation and the Future

Looking forward, the defense of the spectrum will rely heavily on software-defined radio (SDR) and cognitive radio technologies. These advancements allow radios to be smarter, sensing the environment and finding clear frequencies automatically. The community is at the forefront of experimenting with these tools. By pushing the boundaries of what is possible with limited power and bandwidth, amateur operators often innovate solutions that are later adopted by the commercial and military sectors. The fight against spectrum pollution is driving the development of better filters and more robust digital protocols.

This technological evolution transforms the operator from a passive user into an active researcher. It makes the pursuit of a license an entry point into a world of high-tech experimentation. The threats facing the spectrum are forcing the community to up its game, resulting in a renaissance of technical learning. Men who engage with this subject find themselves gaining proficiency in computer networking, antenna physics, and signal processing—skills that are highly transferrable and economically valuable in the modern marketplace. The defense of the hobby thus becomes a pathway to professional development and technical mastery.

The Role of Organized Advocacy

No individual can fight the telecommunications lobby or the tide of electronic noise alone. The response is coordinated through national and international bodies that represent the interests of the non-commercial user. Organizations act as the shield, employing legal experts and engineers to testify before government commissions and international bodies like the International Telecommunication Union (ITU). They monitor legislative proposals, file comments on rule-making proceedings, and alert the membership when immediate action is required.

Supporting these organizations is a key part of the community response. It involves a recognition that rights must be defended collectively. The effectiveness of this advocacy depends on the size and engagement of the membership. A large, active body of licensed operators commands respect in Washington and Geneva. It signals to regulators that this is a voting block and a skilled workforce that cannot be ignored. The political aspect of spectrum defense is dry and often bureaucratic, but it is the trench warfare that keeps the frequencies open for the operator to use.

Natural Threats and Solar Cycles

The spectrum is also subject to threats that are entirely natural and beyond human control. The sun, the ultimate source of all radio propagation on Earth, goes through eleven-year cycles of activity. During the peak of these cycles, solar flares and coronal mass ejections can cause radio blackouts, wiping out communication across entire hemispheres. While this is not a “threat” in the sense of a malicious actor, it is a challenge that requires a deep understanding of space weather. The operator must know how to read the solar indices and adjust their strategies accordingly.

This connection to the cosmos adds a profound dimension to the spectrum. It reminds the operator that they are dealing with forces of nature. The community response to solar weather involves building networks of automated beacons that monitor propagation in real-time, providing data that is used not just by hams, but by scientific institutions. It turns the operator into a citizen scientist, contributing to our understanding of the sun-earth connection. This resilience in the face of natural variation is part of what makes radio operators so valuable during earthly disasters; they are accustomed to adapting to changing conditions.

The Economic Reality of Spectrum Auctions

It is impossible to discuss spectrum threats without addressing the sheer scale of the money involved. Governments view spectrum auctions as a painless way to raise revenue. Billions of dollars are exchanged for the exclusive rights to transmit on specific frequencies. This creates a David and Goliath dynamic. The amateur community cannot buy the spectrum; they can only argue for its value based on public service and educational merit. This is a difficult argument to make in a capitalist system that prioritizes immediate revenue over long-term resilience.

However, the economic argument is shifting. As infrastructure becomes more vulnerable to cyber-attacks, the “insurance policy” value of a trained volunteer radio corps is being reassessed. The cost of a total communications blackout during a hurricane or terrorist attack is astronomical. The community argues that the spectrum they occupy is a down payment on national safety. By maintaining these frequencies for public use, the government avoids the cost of building and maintaining a redundant emergency network of their own. It is a symbiotic relationship, but one that requires constant reminder and defense against the lure of quick auction cash.

Cybersecurity and the Radio Spectrum

The convergence of radio and computing has introduced cyber threats into the spectrum domain. Modern radios are often computers with antennas, and like any computer, they can be vulnerable. Malicious actors can exploit software vulnerabilities to jam networks, spoof signals, or inject false data. The “spectrum threat” now includes the possibility of hostile state actors using electronic warfare techniques to disrupt civil society.

The community response has been to embrace cybersecurity best practices. This includes verifying signal integrity, using digital signatures, and developing “air-gapped” systems that can operate without connection to the public internet. The modern operator must be part hacker, part engineer. This evolution appeals to men who are interested in information security and systems architecture. It frames the license not just as a permit to talk, but as a credential in the field of information assurance.

The Imperative of Self-Reliance

Ultimately, the drive to understand and defend the spectrum is rooted in the imperative of self-reliance. In a world where systems are increasingly interconnected and interdependent, the failure of one component can lead to cascading collapse. The man who holds a radio license and understands the spectrum possesses a tool of independence. He is not reliant on a monthly subscription or a functioning cell tower to ensure the safety of his family or community.

This self-reliance is the core motivation that drives the community response. It is why they build their own antennas, why they fight the HOAs, and why they study for the exams. It is a refusal to be helpless. The spectrum is the medium through which this independence is exercised. Protecting it is protecting the ability to act when others are paralyzed by a loss of connectivity. It is a masculine pursuit of competence and readiness in an unpredictable world.

Conclusion: The Future of the Frequency

The future of the radio spectrum is far from guaranteed. It stands at a crossroads between total commercialization and a balanced model that preserves public access. The threats of noise, regulation, and encroachment are unrelenting. However, the response from the community has been equally persistent. Through technical innovation, political advocacy, and a commitment to service, the guardians of the airwaves are holding the line.

For the man looking from the outside, this struggle represents an opportunity. It is a chance to join a fraternity of capable individuals who are not content to be passive consumers of technology. By engaging with the subject, understanding the physics, and eventually stepping up to earn the credentials, one becomes part of the solution. The spectrum is a heritage and a responsibility. It requires vigilant defense to ensure that when the world goes silent, there is still a signal in the noise, clear and strong, ready to carry the message.

Call to Action

If this breakdown helped you think a little clearer about the threats out there, don’t just click away. Subscribe for more no-nonsense security insights, drop a comment with your thoughts or questions, or reach out if there’s a topic you want me to tackle next. Stay sharp out there.

D. Bryan King

Sources

Disclaimer:

The views and opinions expressed in this post are solely those of the author. The information provided is based on personal research, experience, and understanding of the subject matter at the time of writing. Readers should consult relevant experts or authorities for specific guidance related to their unique situations.

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Lobo has a radio receiver in his brain!
So cool.
#Lobo #RadioReceiver

1978 Vintage Stereo Receiver with Dials and Knobs

The image shows a classic stereo receiver from the late 1970s or early 1980s.
It has a silver and black color scheme, featuring dials and knobs for controlling various functions such as tuning, volume, and input selection.
There is also a needle on the display, indicating the radio station being listened to.
The receiver brand appears to be "Sony," but this information cannot be confirmed from the image alone.

https://nocontext.loener.nl/fullpage/05-May1978-Page-067.png

#photography #illustration #madman #nocontext #sfw #vintage #stereo #electronics #radioreceiver #Sony #audioequipment #homeappliances #oldtechnology #retro #nostalgia

TECSUN R-912 FM/AM/단파 수신기
@[email protected] 님이 무료 나눔 해주셨습니다. 감사합니다!
#radioreceiver #swreceiver

1974 An old radio with numbers and buttons

This image showcases a vintage radio, steeped in nostalgia, with a plethora of buttons and numerical details.
The radio, a classic example of the electronics genre, is not just a radio receiver, but also includes a clock radio feature, making it a multifunctional device.
Its design harks back to an era where stereo systems were a household staple.
The radio potentially could have an amplifier integrated into its design, enhancing the sound quality for its users.
The radio is situated indoors, hinting at its role in creating a musical ambiance within the space.
The presence of text across the radio suggests labeling for ease of use, a common design trait in such devices.

#photography #illustration #madman #nocontext #sfw #electronics #text #electronicdevice #radio #radioreceiver #clockradio #stereo #receiver #amplifier #indoor #music

https://nocontext.loener.nl/fullpage/01-January1974-Page-044.png

Step-by-Step Guide: Build an ESP8266 FM Radio with Infrared Remote Control and TFT Display - Techrm

In this article, we will explore together how to transform your ESP8266 into an ESP8266 FM radio, i.e. a frequency modulation receiver controlled by an

Techrm

Owning A ShortWave Radio Is Once Again A Subversive Activity

An abiding memory for a teen fascinated by electronics and radio in the 1970s and 1980s is the proliferation of propaganda stations that covered the shortwave spectrum. Some of them were slightly surreal such as Albania's Radio Tirana which would proudly inform 1980s Western Europe that every village in the country now possessed a telephone, but most stations were the more mainstream ideological gladiating of Voice of America and Radio Moscow.

It's a long-gone era as the Cold War is a distant memory and citizens East and West get their info from the Internet, but perhaps there's an echo of those times following the invasion of the Ukraine. With most external news agencies thrown out of Russia and their websites blocked, international broadcasters are launching new shortwave services to get the news through. Owning a shortwave radio in Russia may once again be a subversive activity. Let's build one!

Whatever Happened To The Portable Radio?

A typical small world band radio. Donald Trung Quoc Don (Chữ Hán: 徵國單) CC BY-SA 4.0 International.

There was a time when everyone had a radio, and radio listening was a universal occupation. From 1930s families clustered round an ornate family radio to the teenagers of the 1960s and 1970s with their portables, it's a defining 20th century image. Though many of us still listen to radio here in 2022 the chances are that we no longer do so over AM and certainly not over shortwave. We can get instant access to almost any content online, so it's by no means certain people will have a radio. If those shortwave transmissions are starting again, how can their intended audience pick them up? Perhaps it's time to look at shortwave radios with a 2022 slant.

If you lack a shortwave radio and a dig around all your family's junk hasn't turned up a relic from decades past, then the simplest way to get one is of course to buy one. AliExpress is full of "world band" radios starting from somewhere under $20, and if you don't mind waiting for shipping from China then it's the path of least resistance.

But there's the problem, international events are moving fast and there might not be the luxury of waiting three weeks, or even for that matter of being able to order one at all in a warzone. How can you make one? Yet again there's an extremely simple option in the Silicon Labs series of one-chip radios. These provide a high-performance shortwave receiver with a minimum of external parts, and really are a miracle of integration. But yet again, in a warzone and in the middle of a chip shortage they just might not be an option. So how can you make a shortwave radio receiver using what parts might be at hand from available consumer electronics? We'll first be taking a look at some possible avenues, and then introducing a few of the readily available building blocks.

Where Do You Start?

The best way to start is to look at the things that you might already have. Such electronic flotsam and jetsam as battery-powered AM radios, car radios, or even $10 RTL-SDR sticks. All of these can be modified or converted to receive the shortwave broadcast bands, often with readily available parts.

Probably the simplest method possible might be to directly modify an existing AM radio. I'm indebted to [Phil M6IPX] for passing me on an instructables link for a method to do this. It involves changing the resonant frequency of the ferrite rod antenna coil in the radio, and I'm guessing, relying on a harmonic of the local oscillator father than the fundamental to do the mixing. It doesn't cover all the broadcast bands, but it might do at a pinch.

Block diagram of a receive converter

The next method lies in converting the shortwave signal from its original frequency to one that can be received by a radio you already have. Radio amateurs will be familiar with the receive converter, a device that mixes the signal from an antenna with a fixed frequency local oscillator to produce an intermediate frequency of their difference, and it should be relatively straightforward to use this technique.

An AM radio tunes in around 1 MHz and can be used with a converter to cover just one of the many shortwave broadcast bands. [Phil] again suggested a 16 MHz crystal oscillator module might be used with a mixer to tune the 15 MHz (19 m) broadcast band onto an AM radio, and a commonly available 4.433 MHz PAL colourburst crystal with a simple transistor oscillator might do the same for the 5 MHz (60 m) band. If I were making such a rough-and-ready converter for an AM radio, I'd try to find a car AM radio to serve as my IF, because these radios are well screened and have a handy co-axial antenna input.

My one-inch converter PCB

Meanwhile an RTL-SDR can be modified for shortwave reception by either modification or by using a converter. The direct sampling hack bypasses the onboard tuner chip to pipe signals directly to the SDR chip and can be performed by anyone with good SMD soldering skills, and for those unwilling to try it an alternative approach is to use a converter with a 50 MHz oscillator. A few years ago I produced such a converter using a CMOS chip as my entry in the Hackaday Square Inch competition, but there are even simpler circuits to be found.

Finally, perhaps the simplest usable shortwave radio is the direct conversion receiver. Its principle is similar to the receive converter in that the signal from the antenna is mixed with that from an oscillator to yield the difference between the two, and when the local oscillator is the same frequency as the desired station that difference can be fed to an audio amplifier and listened to. It requires three relatively simple circuits in oscillator, mixer, and audio amplifier, and while it doesn't provide acceptable performance for music radio it's fine for speech.

The Nitty Gritty: Parts And Circuits

Having fired everyone up about receive converters and direct conversion receivers, it's time to take a look at those building blocks. How can you make them from the components you'll find in electronic junk, without ready access to the global electronic parts supply chain?

There are many ways to make oscillators and mixers, but for our purposes the components we are interested in are crystal oscillator modules for the local oscillator, wideband RF transformers for the RF coupling, and diodes as the mixer elements. Variable frequency oscillators are a little more tricky to build but can be made from the most basic of components, but if you have a signal generator or even a Raspberry Pi with appropriate software you can use them instead.

Crystal oscillators are ubiquitous on all sorts of PC expansion cards and other computer boards, and provide a logic-level squarewave on their output pin when provided with 5 V. Meanwhile any Fast Ethernet interface will contain an RF transformer, and small signal diodes can be found across multiple different types of electronics. Beyond these parts there may be a need for the normal discrete components such as transistors and passives, but yet again these can be scavenged from a wide variety of sources.

This is the basic made-from-junk diode ring mixer. It's not perfect, but it works.

A diode ring mixer is a very straightforward circuit using a couple of RF transformers and four diodes. It works by using the diodes as switches operating at the local oscillator frequency to alternately pass and block the signal frequency. The result is the intermediate frequency (IF), which is the difference between the incoming signal and the local oscillator. It can be very easily made with an Ethernet transformer and four signal diodes using the circuit shown. With a 100 Mbit Ethernet transformer, it should have 100 MHz bandwidth. There are multiple ways in which this circuit can be used with a suitable oscillator as either a receive converter for an AM radio or as a direct conversion receiver.

For the converter, simply connect the output of a crystal oscillator module to the local oscillator pin and feed the output to an AM radio, while for a direct conversion use a variable oscillator and connect the output to a sensitive audio amplifier such as a microphone or phono amplifier. The coupling to the AM radio can either be direct to the antenna socket of a car radio, or via several turns of wire wrapped round the case of a portable AM radio. There is a problem with this circuit in that it has no filtering and thus picks up both both the sum and the difference of local oscillator and IF frequencies, but it should be good enough to pull in a shortwave broadcast.

These are not the only ways to make a working shortwave receiver -- after all everything from a crystal set upwards can be coaxed into working -- but we think they are probably the best ways to make one using the electronics likely to be at hand. Perhaps you have some ideas to add to the mix? Leave them in the comments!

#featured #interest #news #radiohacks #hf #radio #radioreceiver #shortwave

Owning A ShortWave Radio Is Once Again A Subversive Activity

An abiding memory for a teen fascinated by electronics and radio in the 1970s and 1980s is the proliferation of propaganda stations that covered the shortwave spectrum. Some of them were slightly s…

Hackaday