OnAir: A Digital TV and DAB Decoder for SDRs rtl-sdr.com/onair-a-digital-…

Indeed, the LA9310 80 GFLOP "VSPA" DSP could turn out to be a better use of silicon than reimplementing the same old downconverters, filters and FFTs on bare FPGA (even expensive FPGA with DSP slices). ADC+DAC+VSPA+M4 fits in 8 mm x 8 mm and draws 1.5 W. Any demos ?

Taylor, binary pulsars, and the Shannon DNA of FT8 - Once you recall where Joe Taylor comes from, the architecture of FT8 and the broader WSJT family becomes almost inevitable. Before he was a Nobel laureate moonlighting among radio amateurs, he was at Arecibo and Green Bank, pulling structure out of relativistic binary pulsars buried tens of decibels below the noise. Extracting orbital elements, period derivatives, Shapiro delay, periastron advance — all from signals so weak they flirt with the thermal floor. That world leaves a deep imprint. You quickly learn that there is no magic — only well-chosen priors, carefully sculpted signal models, and an obsession with driving the message toward minimum entropy. The entire pulsar pipeline — periodicity searches, coherent folding over thousands of rotations, matched filtering through period/Ṗ/DM space — rests on a foundational idea: if you know what the signal “should” look like, you can recover astonishing amounts of information at negative SNR. WSJT/FT8 is that same philosophy, translated for amateur radio: • entropy minimisation (compressed callsigns, rigid message grammar), • energy concentration via long symbol durations, • narrow effective bandwidth to suppress integrated noise, • external time synchronisation to collapse the search space, • and FEC using soft metrics — squeezing every fraction of a decibel, just like a pulsar likelihood engine squeezes meaning from a noisy folded profile. If you’ve spent your scientific life confirming general relativity by extracting a few dozen usable bits from hours of sub-milliJansky pulses, designing a mode that retrieves 77 bits cleanly at –20 dB is almost second nature. And that’s what delights me: FT8 isn’t a digital gimmick. It’s the direct importation of “binary pulsars + Shannon theory” into the amateur bands. Every decode is a miniature pulsar experiment: the decoder explores a model space, computes likelihoods, and selects the minimum-entropy solution compatible with the noise. It’s the same intellectual gesture as searching for millisecond pulsars by folding tens of thousands of trial DMs and periods. Seeing techniques born to measure Shapiro delay at –30 dB reborn as a 15-second mode on 20 meters is, frankly, a scientific inside joke. FT8 is one watt of Arecibo-grade information theory, packed into 77 bits — and it makes the Shannon boundary feel like a playground.

16 Ceramic Satellite Antenna Satellite Guidance Anti-interference Module CRPA Detailed Disassembly

New game for amateur physicists: Guess where my light comes from. (#amateurradio: This is the closest thing we'll have to a spectrum waterfall for light until we bridge the terahertz gap)

Radar and Electronic Warfare : allaboutcircuits.com/uploads…