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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.

6m (50Mhz) Long wire antenna There is another form of long wire antenna which provides uni-directional coverage and is easy to build. Description by Arnie Coro CO2KK

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

If you have space constraint at your QTH for a HF antenna, you can try contructing this HF magnetic loop antenna for 40-20 meters bands

Cheap UHF antenna plans for 2 meters and up including 421 1296 and 902 Mhz

A PDF presentation of a home made moxon antenna for 50 MHz 70 MHz and 144 Mhz. The project is mainly out of surplus plastic Plumbing pipes and clips etc, and also details of how the dimensions were calculated.

This article describes the antenna for Low Frequency Beacon. It originally appeared in the "Lowdown" for Oct. 1999.

A flex antenna working on 6m and 70cm by K0EMT

Shortened vertical antenna for 40 meters band an homebrew project

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

A trapped dipole antenna based on the orignal W3DZZ antenna design resonating on 80 40 20 15 10 meters

Article on a 2 and 6 meters halo antennas that does not require a mast has a very low part count and can easily be built with a minimum of tools.

K0EMT mobile antenna mast mount

Although a magnetic loop antenna(aka small loop antenna) is very compact, its efficiency is close to a half-wavelength dipole if carefully built.

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.

Find the best placement of a mobile antenna

4 elements Yagi antenna for 28 MHz

Drawing and plan for an HF magnetic loop antenna

The 5/8 vertical it quite popular and matching solutions can vary

This article explores the Cobra Junior linear loaded antenna for 80m to 10m bands. This antenna is a linear loaded dipole described by W4JOH in 73 magazine June 1997

A bowtie antenna is a type of antenna that reputedly provides higher gain at lower radiation angles than a center-fed dipole antenna at heights considerably less than 1/2 wavelength above ground.

A Low -Power Indoor Portable HF Antenna by Monty Northrup, by N5ESE

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

A vertical monoband antenna design that can work from 6 meters to 70 cm by F5ZV in French

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

A New Twist on Portable Multiband HF Dipoles, a Multi-band Spiral Dipole Off-Center-Feed match (OCF) antenna solution.

A simple VHF vertical aerial for the home station

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

HB9MTN Capacitive antennas for 40m, 30m AND 20m

A folded dipole using twin lead By W8HDU

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

A project of a bobtail-curtain antenna for 10 MHz

Loop antenna picture gallery

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

DIY a Wi-FI Helical Antenna for better performances, a project by PA0HOO i Dutch end English

Alford slot antenna for 1.3 GHz to 2.3 GHz.

EWE Antenna plan with a 9:1 balun

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

A VHF UHF 5+5 elements yagi antenna by CE4WJK

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

A method for supporting a balun on a Chushcraft A3S antenna. This allows the balun to be isolated from the boom, thus reducing the effect of introduction of reaction with the balun core.

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

An HF multiband trapped antenna in french

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

An homemade portable trapped dipole antenna for 40 and 80 meters band with an optional extension for the 20 meters.