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This site serves a community of volunteer and paid professionals in Search & Rescue and Civil Air Patrol who save lives and Amateur Radio enthusiasts who use DF skills as a hobby. We provide antennas and other resources for people in these fields.

A simple to build full length 20/40 dipole antenna to be used in inverted vee configuration

General article on Baluns at myantennas.com, what is a balun and when to use baluns

A four elements quad antenna for 144 MHz made with PVC pipes

Tests on a preamplifier for 50 MHz installed right at the feedpoint of the antenna.

A step by step approach for a ham radio vertical antenna mount using only a hole, gravel and a piece of plumbing pipe

Metro Vector Network Analyzer is a custom antenna analyzer designed and produced by IZ7LDG.

Use this online calculator to determine the length of a quarter-wave antenna from the frequency. Both metric and English units of measurement are supported.

Demonstrates various practical amateur radio projects and technical discussions through video episodes. One episode details cutting and retuning a _1/4 wave shorted stub_ from 101.7 MHz to 107.5 MHz to safeguard a transmitter's driver stage, alongside insights into advanced _160-meter antenna systems_ like eight-circle arrays and beverage antennas. Another segment covers upgrading firmware on an _ATS-20+_ receiver using AverDudes for improved display and functionality, and a detailed guide on using D-Star DR mode on an _ICOM ID-52A_ for international repeater programming. Additional content includes a deep dive into _OpenHamClock_ as a potential replacement for the HamClock project, updates on _Raspberry Pi 5_ running Trixie OS, and a review of the Choyong LC90 Internet radio with AI integration. The series also features "Ham College" episodes, which meticulously prepare viewers for the Technician Exam by covering topics such as antenna and transmission line measurements, SWR interpretation, and the functions of basic electronic components like rectifiers, relays, and transistors. Practical advice on coaxial cable characteristics, dummy loads, and proper soldering techniques is also provided.

WA0SXV Experience with GAP Titan DX Antenna

Radio wave propagation, Principles of transmission lines, Antennas

An HexBeam antenna project, a 2 full elements on six bands

A small sized and very cheap antenna project that allow you to work on WARC bands with a total gain very close to the dipole in both bands. On 12 meters is a normal dipole, while on 17 is a trapped dipole. Article in Italian

AF6SA USB antenna AZ-EL rotor controller compatible with Yaesu G-5500, G-450, G-650, HY-Gain and other AC motor rotors

The collinear J-Pole, often known as the Super-J, does improve the behavior over a regular J-Pole. As many attest, there is an advantage when vertically combining 1/2 radiating sections to have a bit of separation between the half-wave end points. The Super-J has very little separation between the two half-wave radiators.

This project produces a sturdy tripod for small vertical antenna support using readily available electrical metal tubing (EMT) or conduit

This page describes a cheap, weather-resistant and readily available type of antenna wire by HAMwaves.com

The electrical characteristics of an antenna that are of interest to obtain by direct measurement are the frequency at which the antenna is tuned, the gain and radiation pattern

Telecom Product Profiles is a manufacturers' rep firm specializing in factory direct Nello Towers, monopoles, antenna mounts, shelters, and more. Factory direct Cellular, PCS, and Wireless Broadband equipment such as antennas, radios, and more. Installation, financing, and leasing options available.

A trap on the coaxial cable, also known as choke, helps to eliminate the sneaking of the reflected RF- energy to the shack. The trap can be made from the coaxial cable that feeds the antenna

Dimensions and EZNEC plots for a 2 Element 30 meter Yagi antenna with 28 Ohm featuring 4.3 dBd Gain and a 16dB F/B with a good bandwidth.

VHF UHF half wave flower pot antenna project by VK2ZOI

A project that describes a build a multiband wire beam antenna. A 3 band single feed moxon antenna for 20,15,10 meters.

Antenna model for a diamond loop wire antenna for the 40 meter band

A page dedicated to the Quadrifilar Helical Antennas, with projects, pictures and antenna plans by OH2GVB

Modification of the Bill Petlowany, K6NO antenna by N0LX

Protecting amateur radio equipment from transient overvoltages requires robust lightning and surge protection, which is the focus of Electronic Specialty Products. The company provides various devices, including coaxial lightning arrestors for antenna feedlines and surge protectors for AC power lines and data circuits. These devices are engineered to divert high-energy surges, such as those caused by direct or indirect lightning strikes, away from sensitive transceivers, amplifiers, and computer components, thereby preventing catastrophic damage. Key products include the _Coaxial Lightning Protector_ series, designed for various impedance levels and frequency ranges up to 3 GHz, and the _AC Line Surge Protector_ for shack power distribution. Effective deployment of these protection devices can significantly reduce the risk of equipment failure and ensure operational continuity during severe weather. For instance, a properly installed coaxial arrestor can handle peak currents of **20 kA**, while AC line protectors offer clamping voltages typically below 400V. Comparing different models reveals varying levels of insertion loss and return loss, with some coaxial units exhibiting less than 0.1 dB loss at 500 MHz, making them suitable for high-performance HF and VHF/UHF operations. Integrating these components into a comprehensive grounding system is crucial for achieving maximum protection against both common-mode and differential-mode surges.

Crank-up(telescopic) and tilt-over tower, Ring rotator for mounting an extra antenna, from 16m to 42m, Strong safe and smooth, Radio communication and commercial tower.

C-Poles for 20m and 6m, it is a folded half-wave dipole with an asymmetrical tapped 50-Ohm-point in the lower part of the antenna. Design hints by DK7ZB

After you have build this antenna, you may not need anything else. This article shows how to build a VHF j-pole antenna and how to protect it by inserting it into a PVC tube, the correct way.

Demonstrates the operational status and reception reports for the SK6RUD/SA6RR QRPP beacons, which transmit on 478.9 kHz, 1995 kHz, 10.131 MHz, and 40.673 MHz. These beacons utilize extremely low power, with the 630-meter beacon operating at approximately 0.1 watt ERP into an L-antenna, showcasing the potential for long-distance contacts under favorable propagation conditions. The site details the specific frequencies and antenna types employed, such as a vertical at 500 kHz and a 1/4 vertical for higher bands. The resource compiles over 10,530 reception reports from amateur radio operators worldwide, logging details such as date, time, band, RST signal report, locator, distance, and receiver setup. Notable long-distance reports include a 500 kHz reception by AA1A-Dave from 5832 km in 2008 and a 10.133 MHz reception by ZL2FT-Jason from 17680 km in 2010, illustrating the global reach of these low-power transmissions. Each log entry provides specific equipment used by the reporting station, including transceivers like the Yaesu FT817, ICOM IC-7300, and various antenna configurations such as coaxial mag loops, inverted Ls, and end-fed wires. The primary objective of the SK6RUD beacons is to challenge conventional notions of power requirements for effective two-way communication, proving that contacts over significant distances are achievable with minimal output. The site also includes a submission form for new reception reports, fostering community engagement and continuous data collection on propagation phenomena across different bands. The detailed logs offer practical insights into real-world propagation characteristics and the efficacy of QRPP operations.

A conversion of a 80m dipole into a 160m vertical antenna

Examines the historical role of telegraphy within Canadian railway operations, detailing the evolution of communication systems crucial for train dispatch and coordination. It covers the technical substance of railway telegraphy, including equipment, operational procedures, and the personnel involved, such as agents and operators. The resource provides insights into the **F59PH locomotive** history, development, and components, alongside diagrams of various parts like antennae and traction motors. The content also explores the practical application of these systems by documenting specific railway events, such as the CPR Galt Sub operations from 1895-1971 and GO Transit's operational history. It includes photo galleries, schematics, and diagrams of locomotives and cab cars, offering a visual and technical comparison of different railway equipment. The site also features information on **GO Transit** rolling stock, including MP40s and commuter coaches, providing a historical context for railway communication and transportation.

An indeal stealth antenna made by multiple quarter wave verticals, supported by a tree.

A 5 element yagi beam antenna for ten meters band with full dimentsions, eznec file and coax match informations for 50 ohms feed line

Use this online calculator to determine the length of a full-wave loop antenna from the frequency. Both metric and English units of measurement are supported. Quarter-wave matching section lengths are also calculated.

Butternut article on radials usage on vertical and ground plane antennas

LnR Precision Inc. is a North Carolina based company that specializes in Par EndFedz amateur radio antennas and MantiZ QRP Transceivers. Their most popular products include End-Fed QRP portable antennas and HF FX Series QRP Transceivers.

This is a video review of the yaesu ft-450 amateur radio transceiver. This radio operates on hf and 6m with a built in antenna tuner.

Article on Helical Antennas in french

A Tomato Can Horn antenna for 2304 MHz by Steve Kavanagh

The TMB-1 is an RF amplifier unit / receiving accessory that can be used with a low-impedance broadband loop, a high-impedance terminated loop (such as a Pennant, Flag, or Kaz Delta), and whip (telescoping rod) antennas.

An homemade base plate for the hexbeam antenna

Transverters-Store is a online shop for low cost transverter boards, but also QRP transceivers, Active antennas, RF bridge and probes, Mic equalizers and other amateur radio accessories

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

An homebrew project for a 4 elements yagi monoband antenna for the 10 meters by 9M2MSO

Homemade Jeep Tailgate Antenna Mount for use with a Swing Out Tire Carrier

Largest Capacity of 200,000 MT for Towers & market leader in India with backward integrated rolling & manufacturers of Shelters, V/UHF, Patch Panel Antennas, DIAS & DWDM Equipment

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

A presentation of a HF multi-band sloper antenna. This antenna project is for low band operations, and antenna presented in this article works on 40 80 and 160 meters band. Article is in Polish.