blog
Two CW decoder complaints that looked unrelated turned out to be the same defect pointing in opposite directions. Here's the root cause, the rebuild, and how I tested a decoder without a radio.
Turning the RSGB ETCC's repeater CSV into an interactive map with distances, band and mode filters — and why the most dangerous bug in the whole project was a column name.
Why feedline loss matters more than most newcomers think, the math behind it, and a calculator that includes ladder line — not just the usual RG-58 and LMR-400.
How I built an HF antenna length calculator with SVG diagrams, multiband harmonic analysis, and 50 ohm SWR — covering dipoles, end-fed half-waves, and quarter-wave verticals.
How I built a real-time amateur radio satellite tracker using TLE data, SGP4 propagation, and Leaflet — with pass predictions and frequency info for 8 satellites.
Repeaters extend your range dramatically — but programming one into your radio for the first time is a rite of passage. Here's how offsets, CTCSS tones, and repeater etiquette actually work.
How I built a real-time Morse decoder using the Web Audio API, Goertzel filters, and AudioWorklets — and why the next version will move the heavy lifting to a Python backend.
You've passed the exam, bought a handheld, and now you're wondering why nobody seems to be out there. Here's how to actually make your first contact on 2 metres.
The ionosphere is a dynamic, solar-powered mirror. Here's what's actually happening when HF signals travel thousands of kilometres — and why conditions change by the hour.