direction finding circui

H Doublebay Antennas - Cheap and EZ to build Bi-Directional VHF & HF antennas with gain

Slim Jim Antenna - Slim Jim 2 meter omni directional vertical antenna

WB2HOL Foxhunting beam - Building the WB2HOL foxhunting beam antenna

Switchable Direction EWE Antenna - About Switchable Direction EWE Antenna

Single EWE for Four Directions - More EWEs for You By Floyd A. Koontz, WA2WVL First published in QST (ARRL), January 1996

Eggbeater II Omni LEO Antennas - Presented here is a high-performance, circularly polarized omni-directional antenna that is easy to build, easy to tune, inexpensive, and will work all the mode J Low Earth Orbit (LEO) satellites

Large Antenna in a fixed direction? - If your antenna is fixed in one direction, you will notice that your antenna works perfectly only during fall and spring.

Vertical end Firen Antenna - A bi-directional vertical antenna with 4db gain over a dipole.

LogView - LogView is a FREE post-contest log-visualisation tool, for analysing contest performance. It plots the QSOs in a Cabrillo-format contest-log on to one of 8 different maps by finding the position of each QSO from an online database of about 970,000 W/VE callsigns.

Anaren - Manufacturer for splitter and combiners, baluns, directional couplers hybrid couplers, modulators, mixers, phase discriminators, antenna feeds.

ATV 432 MHz transmitter - ATV 432 MHz AM transmitter schematic

FT-817 DC Circuit Protection - A schematic for a DX circuit protection for the Yaesu FT-817, provides protection from the external power supply overvoltage by DL2LTO in german

Mini Circuits - RF / IF Microwave components DC to 20 GHz

Ansoft Designer - Sesign-management environment and circuit simulator for radio frequency (RF) and microwave hardware development

IC-Prog Prototype Programmer - This software package allows you to program all types of serial programmable Integrated Circuits using Windows 95/98/NT/2000/ME/XP

PCB with kitchen appliances - Cheap and relatively easy way of making professional quality printed circuit boards at home

Low cost frequency counter - Low cost multifunctional seven digit LCD frequency counter, for your HAM radio shack

A simple iambic keyer - Iambic keyer with simple paddles and simple electronic circuit.

Digital Wattmeter - 300nW to 30W - The digital wattmeter project was created for the purpose of measuring power in the range of 300nw to 30w.

KD1JV Digital SWR / Power Meter - This small, light weight digital SWR and power meter uses an Atmel AVR Butterfly demo board and a Stockton type directional coupler.

Signal Source for AO40 mode S - Signal source circuit for 2.4 GHz by sv1bsx

TenTec Omni VI AGC modification - Modification leaves nearly all of the existing Omni agc circuitry intact, simply add an audio detector which modifies the delay characteristics of the original system by G3IXQ

Regenerative circuit - Wikipedia page about regenerative circuits in designing receivers.

A Bipolar Regenerative Receiver - Contrary to what some radio experimenters think, a bipolar regenerative design can be made to work efficiently

The Modern Armstrong Regenerative Receiver - Ramon Vargas Patron articel on regenerative receiver project