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A shortened 160 meters band antenna for hams who do not have 260 ft of space, based on a open-wire-fed short dipoole

This 40 meter Inverted V antenna was tested and tuned at a height of 35 feet and proved excellent results. The ends of the antenna are about 11 feet above the ground. Article and video available

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.

Specialists in shortwave radio, scanners, amateur radio, FRS (family radio), CB radio, antennas, accessories and publications since 1995.

Pipe your signals to 146 and 445 MHz with one antenna!

The HB9CV is a well known two element antenna of a directional beam type with a forward gain of 4 to 5 dBd. This one is for two metres but it can be scaled, from the dimensions in the diagram, for other bands I have also made them for four and six metres

A re-usable control & computing platform for antenna measurement, PSK31 digital modems, audio filtering, signal source & VFO, memory keyer by AMQRP

In the long history of beam aerials there has persistently existed the claim that certain types of aerials perform better than yagis.

Adventures in amplified GPS antenna construction; an experiment

Why twinlead isn't necessarily a low loss feed line.

A homemade VHF/UHF vertical antenna made essentially with RG58 coax cable, with a 9 turns choke balun to prevent the shield acting as a RF Radiator.

About the G5RV antenna, construction notes and tipical dimensions

Theory of horizontal loop antennas, as discovered by G2PL using a lowered quad antenna and theorized by ZS6AKA

This is a design for a stealthy HF multi-band vertical wire antenna using a tree as a supportby G7AQK

An interesting homebrewed gamma match feed for a Halo Antenna

If your doing any home brewing gear for ham radio its a great idea to have a dummy load. This will to your radio be the perfect antenna...it will never radiate but your radio sees a perfect 50 Ohm impedance.

A 50-ohm 10W resistor forms the core of this portable QRP antenna, designed by _K0EMT_ for convenient operation on 160m and 80m. The construction involves soldering the resistor to a BNC connector, with one lead to ground and the other to the center conductor, then insulating the assembly. This minimalist design aims to provide a highly portable solution for low-band QRP operations, acknowledging the inherent trade-offs between antenna size and efficiency. Testing with an antenna analyzer revealed low SWR on both 160m and 80m, with a Yaesu FT-817 confirming good matching. While 40m and 30m showed higher SWR, the primary focus remains on the lower bands. The author successfully tested the antenna with **2.5W CW** output, demonstrating its practical application for QRP field operations where ease of deployment is paramount, even if it means sacrificing some **gain** compared to full-sized antennas.

Offer a wide range of homebrewing projects mainly for VHF UHF operations. From vhf antennas to preamplifiers, chargers and power supplies

Find the best placement of a mobile antenna

A simple center-fed dipole made just with a thin-wall PVC pipe, aluminum tape, and RG-8X coax

3d parts printed to build an EZ-Lindenblad 2 Meters LEO Sat antenna as designed from Anthony Monteiro

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

This article explain how to homebrew and use an HF antenna analyzer by simply adapting a Windows PC, micro-controller and a DDS evaluation board by K6BEZ

how to make a gamma match for a antenna. The Gamma match is the most used matching device used for yagi beams.

Norm's Rotor Service specializes in sales, service and parts for ham radio antenna rotators, antenna rotator, antenna rotors

A project of a bobtail-curtain antenna for 10 MHz

A SQ Loop antenna for 50 MHz, project include pictures and schematic diagram

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.

Building a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

The Quadlong antenna for the six meter band. This antenna feature a total gain of 6,4 dBd, F/B 21 dB and is also available in 70MHz version. Includes detailed pictures and plot diagrams.

A wifi remote antenna switch that can be controlled from a smartphone app

Accurately determining an antenna's feedpoint impedance is crucial for optimal performance, especially when experimenting with new designs or making adjustments. While SWR meters provide basic information, a full complex impedance measurement reveals the resistive and reactive components, which are essential for proper matching. Modern antenna analyzers, like the _Palstar ZM30_ or MFJ259B, simplify this task, but measurements taken through a transmission line require careful interpretation due to impedance transformation. This resource details a calibration method to precisely account for the effects of the feedline. It explains how a transmission line can significantly alter the measured impedance, illustrating this phenomenon with a Smith Chart example where an 80m antenna's [22 + j6] Ohms feedpoint impedance transforms to [82 + j45] Ohms after a 10m line. The guide demonstrates using a transmission line calculator applet, such as the one by W9CF, to reverse this transformation. It outlines the process of calibrating a specific length of RG174 coax, showing how an initial 26ft estimate was refined to **25.85ft** to accurately predict a known 22 Ohm load, significantly improving accuracy over uncalibrated results.

A DIY project of a WiFi 10 elements Yagi antenna

Dedicated to State-of-the-Art lightweight portable radio. Sotabeams produces and sells amateur radio products dedicated to ham radio portable operations. Antennas, supports and masts, filters, wires and more accessories for amateur radio.

A 4 elements handitenna for 70 cm band. This is my version of the K5OE Handitenna. This one is a four Element instead of three, as I had less of a crunch on space than he did. The 1st three elements (Reflector, Driven Element, and Director 1) are the same dimensions as his were.

A 21 MHz Four Square Beam Antenna This popular antenna for the lower bands, can also work well on 15 meters, QST Article

Make your own loading coils for antenna projects using Caterpillar Grommet strips.

The Folded Dipole is not used much amongst Radio amateurs, probably due to the fact that this antenna uses twice as much wire as a single-wire dipole.

A ATU for beam and vertical antennas by PA0FRI

Your source for weather radios, communication headsets, 14 channel radios, M&M groovy radios, smithsonian crystal radio and weather station kits, line restrictors, antennas,ham radio accessories, and battery products.

Canadian dealer, specializes in supply and installation of free-standing towers for commercial and amateur radio use. We also supply ham transceivers, antennas, rotors and accessories.

VHF UHF diplexer by G8MNY

The Fence Fan Dipole a quick, easy and inexpensive multiband dipole antenna

Lot of useful information on experiments on 136 Khz band, with antenna tips DSP infos and notes on their activity in LF.

Authorized ham radio store for Alinco Vibroplex Pryme MFJ Enterprises Mirage Amps Ameritron Vectronics DCI Yaesu Comet Antenna

Development of the Slim Jim antenna for HF

A compact antenna for 160 meters, suitable for hams tha want operate top band buh have a limited space

GJTracker is a antenna tracking program for windows written to be compatible with WSJT

Windows program for analyzing vertical antennas. This program shows the resistance and reactance to be expected looking into a cylindrical metallic tower over a perfect ground. It gives a useful approximation of the values to be expected in a real-world situation.

Icom Kenwood Yaesu MyDel dealer, offer a wide range of ham radio products, transceivers, antennas, rotators, microphonrs, aerials, dummy loads, rf amplifiers and scanners based in UK