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An inexpensive external GPS antenna, for 1.5 GHz band for GPS receiver, If you operate APRS or just need an external antenna for your GPS receiver, here's one that is easy to build yet offers surprisingly good performance in a compact size. Best of all, it uses commonly available components and materials.

Cheap AFSK TNC, APRS for everyone with arduino, BeRTOS and a STM32F100 chip by OM5AMX

FindU.com operates as a robust database archiving **APRS** (Automatic Packet Reporting System) data, including weather, position, telemetry, and message reports. It integrates data from both amateur radio APRS systems and the internet-based Citizen Weather Observer Program. This substantial 58 GB database is hosted on dual servers utilizing data replication, processing approximately 20 new reports per second to provide constantly updated information. The system supports various applications, such as displaying weather reports, tracking position data, and facilitating long-term vehicle tracking. A notable function involves forwarding over 100,000 near-realtime weather observations daily to the National Oceanographic and Atmospheric Administration (NOAA) for accuracy checks and use by NOAA and the National Weather Service. Additionally, it archives APRS reports from the International Space Station. Access to the database is primarily via dynamic web pages, with a comprehensive list of available CGIs detailed on a dedicated server page. While direct URL parameter editing is possible for advanced users, alternative web pages with forms simplify query submission. The platform utilizes **PNG** images for dynamic graphics, a choice made due to past GIF patent issues, ensuring broad browser compatibility.

Soundmodem is a free software defined dual-port Packet-Radio TNC that implement a soundcard as a modem and supports AX.25 protocol. Soundmodem has been tested on Windows XP, Vista, 7, 8, 10 and has proved stable in operation. The Soundmodem may be used to build EMCOMM, APRS, BBS, Node station, for satellites

Configuring the TM-D710 with Garmin Nuvi 350 for APRS setup

How to establish a APRS local gateway from Internet to Radio with a TM-D710 and UI-View, the well known software from G4IDE

Using the RC-D710 Display with any HT The Display Head for the Kenwood D710 mobile APRS radio contains all of the APRS functionality in addition to the normal Radio control functions.

Official aprs.fi iOS app, immediate real-time visibility to APRS traffic near you and around the world.

The Kenwood TM-D710 is designed as a nearly fully self-contained APRS station, with the ability to perform most of the common APRS functions built right in.

When you get out of the car, strap your D710 to your old HT and continue APRS inside

VHF/UHF FM Mobile Transceiver with APRS and EchoLink Functionality official Kenwood UK site

Amateur Packet Reporting System (APRS) operations often require compact, reliable solutions for transmitting position data, particularly for mobile or portable stations. This resource details the construction of the _Tiny Track-I_, a transmit-only APRS tracker designed for straightforward integration with a VHF radio and a Global Positioning System (GPS) receiver. It enables hams to broadcast their location without the complexity of a full-duplex TNC. The project outlines the printed circuit board (PCB) layout and schematic, based on an original design by N6BG, with a personal PCB drawing by SV1BSX. It includes specific component placement and notes an additional 10uF/10V capacitor (C5) for improved IC voltage decoupling, a modification not present in the original N6BG diagram. The unit connects to a computer or GPS via a DB9 female connector. This tracker is ideal for basic position reporting, offering a simple and effective way to participate in APRS networks. Its small footprint makes it suitable for vehicle installations or field deployments where space is limited, providing a **reliable 9600 baud** data stream for location updates.

Exploring LoRaWAN Range, comparing the performance of 1Watt and 100mW LoRa trackers on daily commute. Analyzing APRS tracks, beacon statistics, and visual comparisons to uncover insights and surprises in the world of long-range wireless communication.

This blog post documents the author's journey building an APRS micromodem for amateur radio applications. Using an open-source design by LY2EN, the author assembled a cost-effective Terminal Node Controller (TNC) with SMD components, an Arduino Nano, and a JDY-31 Bluetooth module. The construction process included PCB fabrication, careful component soldering, microcontroller programming, and Bluetooth configuration. A custom 3D-printed case protected the completed device. Field testing in Romania showed the device functioned with a Baofeng UV-5R radio, though antenna limitations affected performance. The entire project demonstrates an affordable DIY alternative to commercial APRS trackers.

Robust PACKET, developed by Spezielle Communications Systeme GmbH & Co. KG (SCS), is an OFDM variant of the amateur PACKET mode specifically engineered for HF operation. This mode utilizes a 500 Hz bandwidth with 60 Hz carrier spacing, employing OFDM with 8 DBPSK or DQPSK carriers. It supports 200 bps using BPSK and 600 bps with DQPSK, with each subcarrier operating at a constant rate of 50 Bd. Robust PACKET leverages the AX-25 frame protocol for data transmission, similar to standard PACKET. Compared to traditional PACKET, Robust PACKET demonstrates enhanced resilience against multipath propagation and fading effects, critical for reliable HF communications. It also exhibits a more efficient spectral footprint, with sidebands extending only to 500 Hz, whereas 300 Bd FSK PACKET can produce sidebands up to 730 Hz. Operational frequencies for Robust PACKET include 3.61 MHz, 7.0473 MHz, 10.1473 MHz, and 14.1033 MHz, with specific regional frequencies also documented. Decoding software options for Robust PACKET include Wavecom W-Code and Wavecom W-Spectra. The mode is primarily supported by SCS's 'Tracker / DSP TNC' hardware.

Demonstrates the operational status and reach of the LoRa APRS infrastructure, providing a live mapping and logging service for network participants. Users can verify network coverage, monitor _iGates_, and track mobile stations, observing messages and real-time network activity. The platform offers insights into station locations and data flow within the LoRa APRS system, which is crucial for understanding the performance of LoRa technology in Automatic Packet Reporting System applications. This utility helps amateur radio operators understand where transmissions are being received and processed by iGates, and how mobile units are moving within the network. The site's analysis tools provide RF performance monitoring and metrics, enabling users to assess network efficiency and identify areas for improvement. For example, operators can see how many packets are received by specific iGates, or track the path of a mobile station over a **100 km** range, offering practical insights into signal propagation and network reliability for _packet radio_ enthusiasts.