Amateur radio · Electronics · Software

Signals, circuits, and the software in between.

Ham Radio Protocols Deconstructed

A complete, self-contained field guide to the amateur digital modes — from a no-maths first look, through the theory, to full from-scratch reproduction specifications for every native protocol. Four ways in, by background:

The Beginner’s Tour of the Digital Modes
Start here if you’re new: every protocol in the catalogue explained from zero, easiest first, with diagrams. No maths, no prior radio knowledge assumed.
The Mathematics of the Digital Modes
The intermediate guide: the theory behind every operating principle (correlation and matched filters, Shannon, CRC algebra, Hamming/Reed–Solomon/Viterbi/LDPC, interleaving, LFSRs, source coding), each derived gently and pinned with one fully worked, machine-verified numeric example.
Protocol Commonalities
An engineer’s guided tour of the shared building blocks (modulation, sync, CRC, FEC, interleaving, source coding, receiver DSP), built up from the simplest concepts (OOK/FSK) to the full stack. Read this first for the why; the per-protocol specs give the what.
Protocol reproduction specs
Full, from-scratch reproduction specifications (algorithm + every constant/table) for every native protocol: the WSJT-X family, the fldigi modems, and the LoRa/Meshtastic stack. One document per protocol.

Operating System Experiments

A separate strand: a language and the bare-metal kernel that runs it, a Psion Series 5 rebuilt natively on a microcontroller, a browser engine written from scratch, and a desktop operating system assembled out of all three.

Operating System Experiments
Five projects that turned out to be one. FlowBASIC and FlowMachine, the ESP32 Psion, the ESP32 browser, and Path OS - with what each one is, what it measures, and what is not built.

CNC machining

Software for the Makera Z1 CNC machine in the workshop: getting job files onto it, and drawing the things it cuts.

Makera Z1 Sender
Upload files direct to the Makera Z1 from your Mac or Windows machine, or android if you prefer (SMB/DAV support included) with no fuss, no muss. iPad/iPhone test-flight app to follow.
PCB Tool
A simple in-browser CAM tool to create PCBs (and more - gears, signs and engravings) for cutting on the Makera Z1.

Writing a Web Browser from Scratch

What building an HTML, CSS and JavaScript engine twice over taught me about how to go about it: where to start, what to test against, and which of my own measurements turned out to be lying.

Writing a Web Browser from Scratch
Two engines from one codebase, one on an ESP32-S3 microcontroller and one on macOS passing 84.5% of the Web Platform Tests it is measured against. Mostly about the development approach: starting at 80:20, holding the language engine to a stricter standard, wiring up the official conformance suites early, and treating the test harness as a component with its own bugs.