hl 60u circuit

Home made GPS antennas - A Home made Helical antenna for a GPS

Antentop: Loop Antennas - Article on radiation patterns of small loops, equivalent circuits of loop antenna, small loops as receiving antennas, ferrite loops

Remotely-tuned loop antenna for LW and MW - This article describes how to build a loop antenna for low frequency (LF) and medium wave (MW) reception with remote-controlled tuning. The antenna is extremely sensitive and can be built mostly from parts from old radios and tape recorders. Like all loop antennas, it is highly directional, which allows you to null out unwanted noise sources.

Magnetic antenna fo ULF - Detection and recording of Schumann resonances and other electromagnetic phenomena at frequencies below 50 Hz By Hans Michlmayr

Multi Band Antenna Traps - These devices are called Traps, but they are actually more like frequency sensitive switches. They are parallel resonant, high Q, tuned circuits which provide a very high impedance at their frequency of resonance.

Emtech ZM-2 Antenna Tuner Kit - The Emtech ZM-2 Antenna Tuner is a nifty little portable transmatch for QRP (low power). It utilizes the well-known Z-match circuit, which is especially useful for balanced antennas (like dipoles and loops).

US HF Amateur Bands - US ham radio band plan in pdf available for download and print

K8HO Highland ARA - The Highland Amateur Radio Association (HARA) centers itself in Hillsboro, Ohio.

CRES Amateur Radio Club - We are a general purpose ham radio club serving Columbus and the Central Ohio area. We run the W8ZPF repeater, 146.67-, located in Columbus, and hold bi-monthly meetings on topics of interest to radio amateurs.

Rajessh Eng. The Tower Company - Rajessh Engineers is a general Purpose designing, fabricating, and commissioning of communication towers, transmission towers, sub-station structures and their accessories. Rajessh Engineers located at IT Highway, Sholinganallur, Chennai, Tamil Nadu, India. Rajessh Engineers is an engineering steel fabricating company to meet the highly specialized needs of the communication, power industry.

PSK31 Interfacing - PSK31 basics and radio to pc soundcard interface circuits, radio to soundcard, soundcard to radio and pc serial port to radio

G4ILO Stealth Amateur Radio - If you are a ham and live in a modern urban or suburban development, putting up a highly visible antenna may make it difficult to stay friends with your neighbours.

Far Circuits - FAR Circuits is exclusively a manufacturer of Printed Circuit Boards for electronic projects that are used by the Amateur Radio and electronic hobby enthusiast.

ExpressPCB - Free PCB software is a snap to learn and use. For the first time, designing circuit boards is simple for the beginner and efficient for the professional.

DesignWorks - Commercia, productive and easy-to-use electronic circuit schematic drawing tool Featuring full hierarchical design, standard and custom netlist formats, extensive symbol libraries, scripting and customization features and much more.

ViPEC Network Analyzer - This program intended for electronic circuit analysis (mainly for Linux). ViPEC is a powerful tool for the analysis of high frequency, linear electrical networks.

Grig Radio Control - Grig is a freeware simple Ham Radio control (CAT) program based on the Ham Radio Control Libraries (Hamlib). It is intended to be highly generic presenting the user to the same graphical user interface regardless of which radio is being controlled. Grig supports the most commonly used CAT commands that are implemented by Hamlib, and integrates well with other ham radio programs like Xlog and gMFSK. Grig has been developed on Linux, but has been ported on Mac and Windows OS.

Qucs - Quite Universal Circuit Simulator Priority listing - Qucs, briefly for Quite Universal Circuit Simulator, is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit. After that simulation has finished you can view the simulation results on a presentation page or window. Run on Linux.

TANKIT Priority listing - A free design aid for vacuum tube linear RF power amplifiers. Determine plate circuit operating parameters and design pi or pi-L tanks quickly and easily.

Medium Frequency Amplifier Circuits Compared - Mark Connelly, WA1ION article on Medium Frequency Amplifier Circuits in PDF format, include some RF amplifier schematics

Rotator Brake Delay and Protection Circuit - A rotator modification by W4ZT

Audio processor for SSB transceiver - This circuit consists of microphone amplifier and a high pass filter. Suitable to improve signal readability.

NiCad battery charger - A basic nicad battery charger using a single medium power transistor.

A low cost UHF/VHF duplexer - Duplexers for dual band radio are usually high pass filter and low pass filter combined in the same box. This circuit is a design within a cost of US$10.

Universal QRP Transmitter - Here's the homebrew Universal QRP transmitter adapted from work by Wes Hayward - W7ZOI. The circuit originally appeared in QRP Classics published in 1980 by the ARRL