Welcome to OpenRF Note. This notebook is a dedicated workspace for documenting practical radio frequency (RF) engineering, wireless telemetry, sensor nodes, and unlicensed sub-1GHz through microwave communications.

The Unlicensed Philosophy

Most wireless discussion online gets pulled into two extremes: amateur radio (which requires an individual operator license and strictly bans payload encryption) or proprietary, closed hardware ecosystems.

OpenRF Note takes a different path: lawful, unlicensed wireless for builders. Under regulatory frameworks like FCC Title 47 CFR Part 15 in the United States and ETSI in Europe, manufacturers handle rigorous laboratory testing for spurious emissions and spectral masks. Once equipment authorization is granted, end users can legally operate compliant transceivers without individual station licenses, operator callsigns, or bans on payload encryption — giving builders complete freedom to run strong AES-128 and AES-256 payload security.

What You Will Find Here

  1. Exhaustive Channel Rosters Across All Bands: Every single channel mapped down to exact center frequencies, bandwidth spans, and regional rules across 2.4 GHz, 5 GHz, and 6 GHz, LoRa & Mesh, Wi-Fi HaLow 802.11ah, and Z-Wave / ZWLR.

  2. Interactive Frequency Overlap & Coexistence Visualizer: Real-time visual spectrum charts in our Frequency Overlap Guide showing exactly where Wi-Fi 1/6/11, Zigbee channels 11–26, Bluetooth advertising, LoRa US915 sub-bands, HaLow video carriers, and Z-Wave collide — along with proven “golden profiles” for interference-free multi-radio setups.

  3. Protocol Blueprints & Packet Framing: Deep-dive wire frame formats, airtime formulas, and modulation physics in our Protocols Hub:

    • LoRa, MeshCore & LoRaWAN: CSS spreading factors, private (0x12) vs. public (0x34) sync words, and MeshCore’s structured node roles (Clients, Repeaters, and Room Servers) vs. Meshtastic flood routing. See our full field guide: What LoRa Actually Is: Physical Layer Mechanics, FCC Part 15, and the 1-Watt Trap.
    • Wi-Fi, HaLow & ESP-NOW: 802.11 MAC framing, Beacon management inspection, 10x downclocked 802.11ah OFDM, and sub-5ms connectionless ESP-NOW action frames.
    • Sub-1GHz FSK / OOK & Sensor Decoding: Manchester, PWM, and PPM timing waveforms, CC1101 hardware correlator registers, and step-by-step reverse engineering of 433 MHz weather telemetry.
    • Z-Wave, ZWLR & Low-Power Automation: ITU-T G.9959 MAC frames, Command Classes, Security 2 (S2) Curve25519 authenticated encryption, and 1-mile ZWLR star topology with Dynamic Power Control.

  4. Workbench Notes & Modular Hardware: Schematics, BOMs, solar power nodes, battery management, and carrier PCB designs using pre-certified modular radios (CC1101, SX1262, Morse Micro MM6108, Silicon Labs ZG23, and ESP32).

  5. Defensive RF Diagnostics & Field Auditing: Passive Wi-Fi site surveying, beacon frame logging, RSSI mapping, logic analyzer pin inspection, and decoding open public telemetry with SDRs and handheld multi-tools.

What You Will NOT Find Here

This is strictly an engineering and diagnostic notebook:

  • No Penetration Testing or Exploits: We do not publish, document, or teach RF attack methods, penetration testing exploits, deauthentication frames, packet injection, or methods to defeat access controls (with or without permission).
  • No Jamming or Pirate RF: We do not host circuits or firmware designed to jam, overpower, or operate outside legal FCC Part 15 frequency, bandwidth, and EIRP limits.
  • Diagnostics Only: All monitoring techniques documented here are passive listening and channel health checks used for site surveys, airtime compliance verification, and bench debugging.

Fast, Offline-First Architecture

This notebook is built for field resilience:

  • Instant Search: Press Ctrl+K anywhere on the site to search the entire notebook with zero network roundtrips using Pagefind.
  • Zero External Trackers & CDNs: All fonts and icons are self-hosted and bundled locally.
  • Pure Static Performance: Built with Astro and deployed on Cloudflare Workers edge.

Explore the Bands & Frequencies Hub, test the Frequency Overlap Visualizer, dive into the Protocols Architecture, or read our deep-dive on LoRa Physical Layer Mechanics & FCC Part 15 to get started.