Below the Noise Floor
Below the Noise Floor is a self-education project turned podcast. One licensed amateur radio operator learning HF radio and AetherSDR from the ground up - the bands, the waterfall, the voice chain, the digital modes, the antennas - and sharing the process. These episodes are mostly AI-generated content built around real curiosity and real equipment. If you are new to HF or new to software-defined radio and want something that starts from zero and builds methodically, this might be exactly what you were looking for.
Episodes
18 episodes
Below the Noise Floor — Episode 13: "The AetherSDR Voice Chain, Part Two: EQ and Processing"
With a clean baseline signal established in Episode 12, this episode covers the refinements: transmit equalization, speech processing and compression, VOX sensitivity and hang time tuning, and how to save everything as a profile. Part two of two.
Below the Noise Floor — Episode 24: "CW for People Who Do Not Intend to Become CW Operators"
This is not an attempt to talk you into becoming a CW operator. It is the narrower argument: that a small amount of Morse knowledge makes you a better listener and a better judge of what your antenna is actually doing, even if you never send a ...
Below the Noise Floor — Episode 12: "The AetherSDR Voice Chain, Part One: The Basics"
The AetherSDR transmit voice chain has enough controls to be genuinely overwhelming the first time you open it. This episode cuts through that by starting from zero and walking the signal path from microphone to antenna one stage at a time. Part o...
Below the Noise Floor — Episode 23: "Bonding, and the Panel Where Everything Comes In"
Lightning protection is not really about lightning. It is about potential difference, and once you see it that way almost every decision gets easier.Your radio is connected to two separate worlds at once: the coax that goes outside and u...
Below the Noise Floor — Episode 11: "Noise Reduction and AGC"
Noise reduction and AGC are two of the most misunderstood controls in SDR software - not because they are complicated but because they solve different problems. This episode explains what each one actually does, when to use it, when to leave it al...
Below the Noise Floor — Episode 22: "Height, and What Is Underneath It"
Last episode was the noise you make yourself. This one is the question that follows it: not what antenna to build, but how high you can get the one you already have. In this episode: Why height is measured in wavelengths and...
Below the Noise Floor — Episode 21: "The Noise You Make Yourself"
Phase 5 begins with the thing the show is named after. For most operators in most houses, the noise floor is not something that arrives from outside. It is something you are generating yourself, inside your own walls, and it is very likely the ...
Below the Noise Floor — Episode 10: "Receive Filters Explained"
Receive filters are the single most powerful tool for pulling a signal out of a noisy band - but only if you understand what they are actually doing. This episode covers the fundamentals of digital filters, passband width and shape, high and low c...
Below the Noise Floor — Episode 9: "FT8: Making Your First Digital Contact"
FT8 is often the easiest path to a first HF contact - no microphone nerves, no real-time conversation pressure. This episode covers the full transmit setup: audio routing from WSJT-X through AetherSDR, CAT control, the FT8 contact workflow from fi...
Below the Noise Floor — Episode 8: "Making Your First Voice Contact"
Every HF operator remembers their first contact. This episode walks through exactly how a voice QSO works - the structure of a contact from first call to signed off, how to call CQ, what to say when someone responds, the standard exchange, and the...
Below the Noise Floor — Episode 7: "Before You Transmit: Audio Setup"
Before you key up for the first time there are a handful of things to check and configure - and doing them in the right order saves a lot of frustration. This episode is the pre-transmit checklist: microphone selection and level setting, PTT optio...
Below the Noise Floor — Episode 6: "Digital Modes on the Waterfall: FT8 and Friends"
FT8 has transformed HF amateur radio over the last decade - it is now the dominant mode on most bands. This episode explains what FT8 actually is, how it works, what it looks like on the waterfall, and how to set up WSJT-X alongside AetherSDR for ...
Below the Noise Floor — Episode 5: "Receiving Voice: SSB and AM"
SSB voice is the dominant mode for human conversation on HF, but it sounds wrong until you tune it correctly. This episode covers upper and lower sideband, why the convention exists, how to tune a voice signal by ear, and how to use AetherSDR's mo...
Below the Noise Floor — Episode 4: "The HF Bands in Practice"
Not all HF bands behave the same way. Some come alive at night, some peak at noon, some only open during high solar activity. This episode is a practical band-by-band tour of the amateur HF spectrum - what each band is used for, when to listen, an...
Below the Noise Floor — Episode 3: "Reading the Waterfall"
The waterfall is the defining feature of software-defined radio. This episode covers how to read it: what strong and weak signals look like, how to tell a voice signal from a digital mode from a CW transmission just by its shape, and how to use th...
Below the Noise Floor — Episode 2: "Getting Started with AetherSDR"
AetherSDR is a free, open-source client for FlexRadio transceivers that runs natively on Linux, macOS, and Windows. This episode covers what it is, why it exists, how to download and install it on each platform, and how to start it up and connect ...
Below the Noise Floor Presents: The Trojan Relay (A Dramatized Special)
A dramatized audio mystery. It starts the way these things always start. Late, alone, tuning the dead grass at the bottom of the band where nothing is supposed to live. Then the static stops in one narrow place, and starts counting. The carrier ...
Below the Noise Floor — Episode 1: What HF Radio Actually Is
High frequency radio has been talking to the other side of the planet for over a hundred years. No servers, no cell towers, no infrastructure - just a transmitter, an antenna, and the ionosphere. This first episode covers what HF radio actually is...