circuit design

3 elements VHF yagi antenna - 3 elements VHF Yagi homebrew antenna designed with YAGIMAX 3. Maximum forward GAIN is about 8,17 DBi. This antenna offering an effective radiation power 4 times greater of the transceiver output by SV1BSX

An antenna for 7MHz local contacts - This article describes the design of an antenna for local contacts on 7MHz, including a simple and efficient matching system that presents a 50 ohm load to the transceiver.

EH antenna for 80 meters F8APF - Based on IZ5CCS design F8APF describe the homebrewing of an EH antenna for 80 meters band

Antenna Trap Calculator - Design your own antenna trap online

Coil calculator - On-line single-layer coil designer

Antenna wire catenary calculator - This is a simple calculator for solving the antenna wire catenary between to end points given the design wind speed, mass per unit length of the wire, wire diameter and Gross Breaking Strength of the wire.

Shortened G5RV - A shortened G5RV antenna design

Mobile 2 meter halo antenna - This HALO design is not ground dependent and can be mounted atop a section of PVC.

6 element yagi for 144 mhz - A 6 elements VHF Yagi antenna designed with YAGIMAX 3 and made by SV1XY with excellent results on local and satellites contacts like UO-14 and AO-27

UHF Yagi for AO-40 - Based on DL6UW Yagi antenna's design-formula The forward gain is 13.6 dBi (about 11.5 dBd) and it's pretty small, about 1,5 m in length

7db tape measure yagi beam for RDF - A 3 element yagi beam antenna made with a tape measure. This design exhibits a very clean pattern and is perfect for RDF use.

NM-ARTS - Amateur Radio Technical Society - A hardware and software project group to support learning and creation radio circuits, general electronics, and uProcessor control systems

Ham Cram - ham radio technician licence - HAM CRAM is free no code AMATEUR RADIO TECHNICIAN LICENSE cram course designed to be given in two, 3 to 3 1/2 hour sessions.

microHAM - Accessories for your hamshack, such as Band Decoders, various types of Antenna Switches, Antenna Stacking devices, special devices designed dedicated for the SO2R operating technique, USB Interfaces, cw keyers and many others

Fortis Wind Energy - Fortis is the world leader in design and manufacturing of high performance stand alone and grid connected wind turbines in the range from 800 watt up to 10 kw.

Degen Design - Multi band mini quad antennas, log periodic and stacked antenna for 144 MHz and 70cm

Structural Components - Designer and supplier of tower reinforcement systems to the wireless industry.

W1TAG WD2XES WE2XGR/3 - Experimental Stations Run by W1TAG WD2XES has been used to study LF antenna design, propagation and communication modes. Signals from WD2XES have been copied as far away as Russia.

ECHO (AO-51) - SpaceQuest, Ltd. - Spacequest ltd. is a leading developer of advanced micro satellite technology, specializing in the design, development, and testing of space and ground components for operation with low-earth orbiting satellites.

D-RATS - D-RATS is a small application designed to provide data communication capabilities with D-STAR radios. It supports text chatting, file transfers, position reporting and mapping, and much more! It is written in Python using GTK to run on multiple platforms.

The Nearly Perfect Amplifier - Original manuscript for what became "The Nearly Perfect Amplifier", discussion of some design features that would be present in a perfect, or near-perfect, amplifier.

144 Mhz power amplifier 4CX250B - This page provides information on the design and practical implementation of a rather inexpensive 144 MHz high power amplifier using a pair of ceramic tetrodes type 4CX250B by LA0BY

20 Amp power supply - A 13.8 volt 20 Ampere power supply project

Fun With Tubes - Dedicated to passing on and preserving knowledge of vacuum tube circuits and techniques

Vacuum tube liquid cooling system - This article describes an alternative to water as the cooling liquid for amateur radio vacuum tube power amplifiers. This cooling system is designed for adequate vacuum tube cooling, reasonable cost, and very low maintenance. By K8CU