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Everything you wanted to know about building stuff but were afraid to ask." This series was originally published in "73 Amateur Radio" between November 1997 and February 1998

A 4 way remote antenna switch project

High gain, good pattern and acceptable bandwidth. These aims can be realized with a radiation-resistance of 25-35Ohms, because the 28-Ohm-feedpoint is very simple to match.

If you want to build a repeater, this is the right place to start. Includes construction projects and reviews of repeater hardware available in the market.

Construction Details for 50MHz-Yagis in DK7ZB-Design

Slim Jim Design and Theory and construction detaoils

50 MHZ Moxon antenna based on the KG4JJH design with some slight modifications in the construction

The Vee Beam antenna project presents a versatile solution for hams, enabling operation across all eight High Frequency bands (80m to 10m) with significant gain on 20m to 10m. This easy-to-construct antenna utilizes two long wires at an angle, enhancing directional performance and minimizing ground losses. With a low visual profile, it is discreet and effective for various applications. The design allows for optimal leg lengths and included angles, ensuring robust performance while maintaining simplicity in construction and operation. The V Beam antenna is an aerial that you can use on all eight High Frequency amateur bands (80, 40, 30, 20, 17, 15, 12 and 10m) with an antenna tuner, and which gives significant gain on the five bands from 20 to 10 meters band.

Construction details and tests about a 2 elements cubical quad antenna for HF Bands (20,17,15,12 and 10m band).

Alan yates vk2zay's ham radio website, homebrew construction, general electronics, high voltage experiments, amateur rocketry, and general geek stuff

Constructional details of the eggbeater II antenna based on EA4CYQ design, by G4ZTD

The Construction Principles for Duoband-Yagis 2m/70cm by DK7ZB

This document details the design and construction of a Vinecom 6N4 dual-band Yagi antenna for the 50MHz (6-meter) and 70MHz (4-meter) amateur radio bands. The antenna features 9 total elements (4 elements for 50MHz, 5 elements for 70MHz) on a 4.236-meter aluminum boom. Computer simulations using MMANA software predict 7.21 dBd gain on both bands with front-to-back ratios of 16.01dB (6m) and 15.37dB (4m). The design uses 12.7mm diameter elements mounted on a 32mm square boom, weighing 5.7kg total. Practical measurements with an MFJ-269 analyzer confirmed good SWR performance across both bands after element length adjustments.

The document provides a comprehensive overview of baluns, which are devices used to connect balanced loads, like dipole antennas, to unbalanced inputs, such as coaxial cables. It covers various types of baluns, including voltage and current baluns, and their design, construction, and testing. The text discusses the importance of baluns in preventing RF currents on coax shields and their applications in Ham radio setups. It also includes practical advice on selecting and using baluns based on antenna impedance and power ratings, along with detailed performance evaluations and construction tips for different balun configurations.

Adventures in amplified GPS antenna construction; an experiment

About the G5RV antenna, construction notes and tipical dimensions

A well documented article about construction and analysis of a horizontally polarized halo antenna for 6 meters band by Dr. Carol F. Milazzo, KP4MD

Construction details of a multiband dipole that can can operate at high power levels, and match its 50-ohm coax feedline without a tuner

This document contains the detailed instructions to build a homemade lindenblad antenna using a twin-lead as dipole elements. This document contains 9 pages and includes a detailed construction sequence and some drawings to build this antenna for UHF and VHF ham radio bands

The utility "NEC-2 for MMANA" is intended for calculation of antenna models made and optimized in program MMANA and for construction and simulation of antenna models using input language NEC-2 and based on MMANA models.

Rotator controller, azimuth & elevation control of rotators (automatic antenna turning) based on commands from computer. A project by Pavel VACHAL and OK1DX - KF9VM

Balun case construction, tipically to host toroid cores. Size of case depends on power to handle. By DL5DBM

Article about types of materials that make the best earth grounding systems

A nice loop antenna project for 28 MHz with schematic diagram, construction details and a complete video instruction

A novel approach to contruction of a gamma match.

An excellently presented article on the design and construction of a medium wave DX Antenna

Home made dummy load by M1HOG

Mailing list for people interested in building radio and electronics equipment from kits or from scratch. Frequent topics include shortwave radio receivers, construction techniques, and ham radio project.

The frequency counter described here was built up using the "sandwich" construction and uses low cost components

Homebrew UHF VHF portable Yagi-Uda antenna design and construction notes for satellite operations

A complete guide to magnetic loop antenna construction, with analysis of multi-turn and single-turn magneti loops, and and insight on choosing the optimal capacitor, or homebrewing your own butterfly capacitor

The construction process of making crimp-on connectors with many pictures and instructions by VE7BZ

Inspired by Milan OK7GU, the goal is to build an universal antenna controller - for different types of rotor, different motor, encoder

T2FD A practical construction article, which first appeared in the Electronic DX Press, contains a number of useful photos and detailed instruction to build this antenna by VK3BVW

It is a simple electronic keyer that proved to be reliable, precise timing and no own phantasy by OK1DX

Comprehensive information page about bi-directional Beverages, including applications, construction details, and tips.

homebrew a frequency counter by M1HOG

A technical interest site for electronic and computer engineering. Intelligent NiCd/NiMH Battery Charger - Construction Project

This document details the design and construction of the PA70H, a 50-watt RF amplifier for the 70MHz (4-meter) amateur radio band. Built around the Mitsubishi RD70HVF1 MOSFET transistor, the amplifier delivers 45-55W output with 3-5W input power while operating on 13.8V DC at approximately 7-8A. The PCB design incorporates multiple protection circuits including overcurrent, SWR, and temperature control. The amplifier features various control modes including GND PTT, +13.8V PTT, and RF VOX. Two versions are available: PA70HLI (requiring 100mW input with additional driver) and PA70H (for 3-5W input). The comprehensive documentation includes circuit diagrams, assembly instructions, and performance data showing successful operation from both 100mW and 3.5W input sources.

An overview of some of the ways, and the key tips on how electronics soldered joints can be unsoldered or desoldered.

Construction and analysis of a low cost omnidirectional horizontally polarized antenna for 144 MHz, including notes on halo antenna stacking

A project of a small CW key where most of the part is mechanical construction and a few just electronics by py2ohh

6 Meter 1/4 Wave Antenna by Mike Fedler N6TWW. A detailed article with pictures of construction details of this 50 Mhz antenna

Article by VU2GT about VHF antennas, how to evaluate performances and models.

Circuit Diagram and Construction of the Bartling RX-40 Joachim Munch DF4ZS

Construction of attenuator, suitable for fox hunts at 144mhz

This is the construction of a copper cactus style j-pole antenna.

Hints for building a W3EDP-Antenna, includes the construction of the 1:4-balun by DK7ZB

KA7OEI article on homebrewing Yagi UDA antennas with practical suggestions and designing notes.

A post about the construction and measurements of a Resonant Feedline Dipole cut for the 10M band