alert system

A Horizontal loop for 80 meter dx - This 80-meter quad loop system requires only supports of modest height—a better single-element antenna may be hard to find by VE2CV

Hex Array - 80/40 Meter Vertical - This page describes a homebrew 80/40 meter trap vertical antenna. Includes an interesting antenna raising system that allow easy setup and tuning.

An End Fed Half Wave Antenna - This end fed type of antenna was marketted in the UK and is a useful system for the portable set-up. Being a half wave, no radials or counterpose wires are needed.

Verticals. Ground systems and some history - Article gives a good overview of the basics and reflects the accepted wisdom from BC antenna work.

The ZS6BKW Multiband HF Antenna - Antenna design from ZS6BKW (G0GSF), similar to the G5RV, but it actually resonates on five bands It’s only 90 ft long 27.51 m, with a 40 ft 12.2 m downlead

Freebanders antenna systems - Yagi Quad's and Verticals simple explanations about freebanders antenna systems

Logbook of the World - LoTW - ARRL's Logbook of the World (LoTW) system is a repository of log records submitted by users from around the world. When both participants in a QSO submit matching QSO records to LoTW, the result is a QSL that can be used for ARRL award credit.

GlobalQSL - Forget about spending expensive time and big money for QSL cards printing, filling out, sorting and sending. Exchange QSL information system.

Calnet Repeater Group - Calnet a multi repeater amateur radio system serving most of California and parts of Nevada. The Calnet system consists of numerous fulltime linked 440 MHz repeaters connecting San Diego to San Francisco and Lake Tahoe.

SCRAMS - The Southeastern Connecticut Radio Amateur Mobile System

AC4XQ Repeater System - Home of the C3I Amateur Radio Group

Shore Points Amateur Radio Club - Our Club Repeater System serves the Atlantic City Area on three Amatuer Bands

Ginlong Technologies - World leading specialist in manufacturing, providing design services for small scale wind turbine systems and parts (<30kW)

RT Systems - Radio Programming - Windows programming software for Icom and Yaesu amateur radios and scanners and receivers by RT Systems. Produce radio programming cables for Yaesu Icom Kenwood radios

Unified Microsystems - W9XT contest card DVK Digital Voice Keyer, morse keyers CW memory keyer, beacon CQ IDer, USB interfaces and more for ham radio operators

BridgeCom - FM Repeaters & LTR Controller Combined manufacturer Dedicated to providing you affordable, reliable and feature-rich communications equipment that Goes the Distance.

E. H. Armstrong - Radio's premier inventor, Edwin H. Armstrong was responsible for the Regenerative Circuit (1912), the Superheterodyne Circuit (1918), the Superregenerative Circuit (1922) and the complete FM System (1933).

K6MVR MVRC Radio Club - The Mt.Vaca Radio Club (Call sign K6MVR ) owns and operates repeater systems in and around Sacramento, California. The systems provide reliable coverage for mobile stations throughout the Sacramento Valley region and beyond to Modesto, Chico, the Sierras, and parts of the Bay Area.

WA6TWF Super System - The Super System has three repeaters on Santiago Peak, one in Anaheim, Orange, Santa Ana, Palos Verdes, L.A., Mt. Wilson, Fullerton, Pleasants Peak, and two in downtown Honolulu. Most of these repeaters have autopatch.

Trusted QSL - Open source libraries and utilities to support using digital signatures for Amateur radio QSL system information like eqsl and lotw. Available for windows macos e linux.

Fcc Lookup System - The FCC Lookup System software uses the standard FCC data files in an advanced lookup system for matching a call sign to a user. The software creates index files to allow rapid searches without modifying the FCC data file. Available for both Windows and Linux.

Aether - Aether is an ham radio logging for the Mac. Aether gives hams logging software that is as powerful, easy to use, and good looking as the operating system it runs on. Designed from the ground-up using Apple’s Cocoa, Aether supports the latest Mac OS X technologies, and provides the experience that Mac users expect.

DXCat - DXCAT is a shareware program dedicated to the Yaesu FT900. It is a CAT system computer control program which enables you to have a total control on your transceiver. by F6GQK

RT Systems - Windows Programming Software by RT Systems for Amateur Radios and Receivers

Using ferrite for interference suppression - Excellent guide to using ferrite cores for interference suppression. Understanding and Solving RF Interference and Noise Problems by Jim Brown K9YC Audio Systems Group, Inc. PDF File