John WB2OSZ

by Jon Adams N7UV LoRa is a chirp-spread-spectrum (CSS) modulation technique using a frequency-shift keying (FSK) radio. The semiconductor chips come out of the factory with everything required to build a LoRa data radio transceiver and a robust data transmission/reception scheme. Additionally, most of the very same chips can

by Jon Adams N7UV This is an attempt to show how chirps work to transmit data! Warning: This has nothing to do with APRS. There's a little arithmetic, but there are some big ideas. If you're interested in the way LoRa chirps generally work, read on!

By Jon Adams N7UV Here's a brief guide on where to find hardware that will work fine for 70 cm LoRa APRS. All the deployments I know of or have actually implemented require 4 things - a radio, a good 70 cm (434 MHz) antenna, a user interface

by Jon Adams N7UV Is LoRa (Long Range) technology magic? No, just good old fashioned math, signal processing, and silicon engineering know-how. What makes LoRa so special? It's a modulation scheme that is fairly unusual in the natural world, save some animals and charged particles interacting with the

https://groups.io/g/netcentral/attachment/1/0/APRS%20Emergency%20Communications%20and%20Net%20Central%20v1.06.pdf This document presents a framework for using APRS in emergency and public service scenarios, emphasizing its real-time capabilities for tracking, messaging, and situational awareness. It introduces Net Central, a centralized coordination concept that

It’s easy to find lots of information about APRS.  Unfortunately, most of it terribly outdated and, quite often, just plain wrong.  A newcomer is completely overwhelmed and doesn’t know what to believe or where to start. The APRS Foundation is attempting to produce high quality modern documentation and

APRS101.pdf was the APRS protocol reference written in 2000.  It is missing decades of corrections, clarifications, and new features.  Implementing a product from this is likely to produce something incompatible with contemporary practices.     For Developers:   For a successful implementation, you need to track down and digest: ·        The original specification.

In 2014, Kenneth W. Finnegan wrote and important paper called Examining Ambiguities in the Automatic Packet Reporting System.  A search for that title will find dozens of copies and references scattered around.  He starts with the problem and attempts to provide a solution: …  This is proving to be problematic due

LoRa APRS represents a significant advancement in the world of amateur radio communication. This innovative technology combines the long-range capabilities of LoRa (Long Range) with the well-established Automatic Packet Reporting System (APRS), offering enhanced performance and exciting new possibilities for radio enthusiasts.   Key Features and Benefits   LoRa APRS operates on

Thanks to Jay DV7GDL for compiling this list of radios with APRS capbility builtin. APRS Radios (and other hardware) as of November 2024   (All radios can send and receive APRS text messages in addition to beacons and have user-accessable TNCs unless otherwise stated.)   In production: * LANCHONLH HG-UV98 5 watt HT.