circuit design

Buddipole by ZR6KMD - A rotateable dipole specifically for the 20m based on W3FF Buddipole design by ZR6KMD

Log Periodic Antenna Design  ^pop - calculates the dimensions and spacings of the elements needed to build a log periodic antenna, given tao, sigma and the lower and upper cutoff frequencies.

Getting the most from your tuner - Here is how to adjust this popular tuner circuit so it transfers maximum power to your antenna without going snap

A remote antenna tuner - Interesting project to remotely control, using a servo control circuit, a common commercial antenna tuner by N30X

Fun With Tubes - A noncommercial site operated by Max Robinson and dedicated to passing on and preserving knowledge of vacuum tube circuits and techniques.

Antique Radio Schematics and Capacitors for Tube Radios - Specializes in antique radio schematics and capacitors. carries antique radio schematic diagrams and electronic circuit service information for american, canadian and european antique radios.

Cabrillo Web Forms - Use these forms to manually enter log data to produce a Cabrillo file and submit it to a contest sponsor. The forms are designed for contesters who used paper logging or logging software that doesn't produce a Cabrillo file.

K8ND SO2R Resources - Ideas and notes on designing a SO2R radio shack room. Includes lots of radio shack pictures used by K8ND as ideas to plan his new radio shack, with contesting in mind.

Comtek Systems - COMTEK uses state of the art design and technology to offer every ham the most advanced antenna systems possible.

Discovery Power Amplifiers - The Discovery series of amplifiers are designed and built in the UK by Linear Amp UK Ltd, one of the world’s leading amplifier manufacturers, specializing in high power RF tube amplifiers. The amplifiers use large GS31 or GS35 ceramic triode tubes. Band coverage 6m, 2m and 70 cms

RAM Mounting Systems, Inc. - Ram mounting systems is a world leader for design and manufacturing of mounting applications. ram mounts offer more than 900 interchangeable components for unlimited uses and configurations.

DXBeam - Located in France, DXBeam designs and manufactures a range of monoband, dual band and triband antennas, rotary dipoles, Moxons and Yagis

TNC-X - TNC-X - The Expandable TNC A new Terminal Node Controller (kit) design based on the Chepponis/Karn KISS protocol. It is implemented using a Microchip PIC 16F628A microcontroller, a CML MX614 Bell 202 modem chip, an 8K Ramtron FRAM

GIGAVAC Ham Radio Relays - Gigavac is a leading designer, manufacturer, and worldwide seller of contactors and high voltage relays using vacuum, gas filled, and high voltage reed relay technology. hv relay applications information with cross reference charts for kilovac / tyco, jennings, and crydom part numbers.

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).

NashvilleAPRS - NashvilleAPRS is a website designed to help APRS users in Middle Tennessee have a single, knowledgeable resource on APRS in the area.

ARDF transmitter for 80 meters - The 80m TX described here is the well known ON7YD ATX-80 and timer, combined and re-engineered to fit a readily available enclosure by G3ZOI

SQUIRL Field Day Logger Software - Squirl field day logger - a no-frills, easy to use software logger designed for field day logging operation. by KC8OPV

Log2000 - Log2000 is a program for logging and tracking QSO's, creating and printing QSL's and QSL labels. Designed for Windows 95/98, Windows NT and Windows 2000.

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.

Ham Log - Ham Log is an easy to use yet powerful QSO logging utility for all devices running Palm OS. Ham Log's design and functionality was designed to meet my needs when mobile and away from my home station.

Easy Kilowatt Linear Amplifier  ^pop - Rf amplifier for hf ham radio service - includes easy to understand designs and penny-cheap construction details

A Homebrew SSB Transceiver for 60 Meters - Description of the design and building of a homebrew phasing-type ssb transceiver for the 60 meter band by Paul Alexander WB9IPA

Homebrew FT 817 Headset - A simple circuit to homebrew your own headset for the Yaesu FT-817

External Keypad for FT-817 - An external keypad for FT-817(ND), for the serious portable/field-day contester/operator. Homebrew it with the free firmware and public circuit diagram. The circuit is very simple and takes power supply from the ACC port of the radio