- Article by By David Knight and Nigel Williams on Impedance Matching, basic principles, popular matching networks, L-Network solutions, materials and components in impedance matching designs
Southeastern Asterisk Radio Networks
- Interoperability solutions via Asterisk based RF Gateways - Southeastern Asterisk Radio Network (SEARN) and the Southeastern Asterisk Amateur Radio Netwok (SEAARN) are designed for the purpose of developing interoperability capabilities amongst diverse communications systems. Digital Amateur Radio Project Association - DARPA expanding the digital experience.
WSPRnet Weak Signal Propagation Reporter Network
- A group of amateur radio operators using K1JT's MEPT_JT digital mode to probe radio frequency propagation conditions using very low power transmissions.
Computer sent/received Morse signals received by amateurs and collected on an online database.
The PropNET Project
- PropNET is an ad-hoc 2-way (and potentially, "more-way") RF-based digital communication network whose activity is reported on the Internet. As participating stations periodically ID and exchange data, they report their activity to an Internet data-collection hub for presentation through this web site.
- This article describes a low-cost vector network analyzer that operates from 200 kHz to 100 MHz, and connects to a personal computer using a USB 1.1 interface By Tom McDermott, N5EG, and Karl Ireland