Field Guide

GopherTrunk Field Guide — the RF, SDR & software-development reference

The GopherTrunk Field Guide is a plain-language reference covering the terms, technologies, algorithms, people, hardware, organizations, and software behind radio, software-defined radio, and the craft of building software itself. Each article is a standalone, long-form definition — no lesson order, no exercises, just information — cross-linked to related entries and to the learning paths. Browse by domain and category, or jump to the A–Z index.

462 entries · A–Z index · Learning path · Glossary

Looking for a quick definition? The glossary has one-line entries. Want to learn in order? Start a learning path — RF & SDR or intro to software development. This Field Guide is the long-form, neutral reference: each article defines and explains one topic in depth, cites its sources, and links to everything related. Entries are grouped into domains — RF & SDR and Software Development — each with its own categories.

RF & SDR

Radio, signals, SDR, DSP, the protocols GopherTrunk decodes, and the people and bodies behind them.

RF & signal fundamentals

The physical quantities and units that describe radio waves and signal power.

Antennas & propagation

How energy radiates from an antenna and travels to your receiver.

Modulation

The schemes that put information onto a carrier — analog and digital.

SDR & DSP

Software-defined radio and the digital signal processing between IQ and bits.

Transforms & algorithms

The mathematics of spectra, error correction, and timing recovery.

Cryptography & cryptanalysis

Ciphers, keys, and the techniques used to analyze and break them — including the obfuscation seen on trunked-radio metadata.

Trunked radio

The concepts that let many users share a pool of channels.

Protocols & standards

The digital and analog systems GopherTrunk decodes, in one uniform format.

Voice coding

The vocoders that compress speech into a few kilobits per second.

Hardware

SDR dongles, tuner chips, and front-end components.

People

Scientists and engineers whose work underpins radio and SDR.

Organizations & standards bodies

The bodies that allocate spectrum and write the standards.

Software Development

Programming languages and the concepts, paradigms, and practices of building software — the craft behind GopherTrunk itself.

Programming languages

The languages used to build software, from systems languages to scripting and the historical pioneers.

Language internals & execution

How source code becomes a running program — compilation, interpretation, memory, and types.

Concurrency & execution models

How programs do more than one thing at a time.

Paradigms & design patterns

Styles of organizing code and reusable solutions to recurring problems.

Principles & code quality

The guidelines that separate maintainable software from a mess.

Testing, tooling & delivery

Verifying that software works and getting it into users' hands.

Hardware (computers & devices)

The computing hardware a developer chooses between — from cloud servers down to the microcontroller — what each is for, what runs on it, and its trade-offs.

Hardware foundations

The parts inside every computer and the ideas that span the whole spectrum from cloud to chip.

Servers & hosting

Where software runs for other people — shared hosting, VPSes, dedicated and home servers, and the cloud behind them.

Personal computers

The machines you build software on — the desktop-vs-laptop trade and what each is for.

Mobile devices

The computers in everyone's pocket and bag, and what it takes to build software for them.

Single-board computers

A complete Linux computer on one small board — the Raspberry Pi and its rivals, and the GPIO header that touches the physical world.

Microcontrollers

The tiny, cheap, low-power chips that run the physical world — no OS, the Arduino, and the wireless ESP32.

Networking & connectivity

How computers reach each other and the internet — the cards, boxes, links, and addresses that move bytes between machines.

Storage & memory

Where bytes live — the drives, chips, and cards that hold data, and the memory hierarchy that ranks them by speed and cost.

GPUs, FPGAs & accelerators

Chips that do specialized work faster than a general CPU — graphics, AI, signal processing, and reconfigurable logic.

People

The engineers and founders who built the computing-hardware world — from the first transistors and CPUs to the boards and chips developers use today.

Organizations & makers

The companies and bodies that design and make computing hardware — chip makers, board vendors, foundries, and the standards groups behind them.

A–Z index