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

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

The G5RV multiband HF antenna, designed by Louis Varney (G5RV) in 1946, is a popular compromise antenna offering good overall performance on most HF bands when paired with an external antenna tuner. The basic full-size G5RV measures 102 feet across the top for 80 through 10 meter operation and is fed at the center via a 34-foot low-loss feed-stub. This interaction between the radiating section and the feed-stub facilitates matching across 80-10 meters with a standard tuner, often eliminating the need for ladder line directly to the shack. The antenna's design center frequency is 14.150 MHz, configured as a 3/2-wave dipole on 20 meters, with its 102-foot length derived from long-wire antenna formulas. Construction details emphasize the matching section, which can be open wire, ladder line (window-type), or TV twin lead. Each type has a specific velocity factor (VF) affecting its physical length for an electrical half-wave on 14 MHz; for instance, open wire requires 33.7 feet (VF 0.97), ladder line 31.3 feet (VF 0.90), and TV twin lead 28.5 feet (VF 0.82). The article provides formulas for calculating these lengths and discusses the antenna's behavior on individual bands, from 3.5 MHz where it acts as a shortened dipole, to 28 MHz where it functions as two three-half-wave long-wire antennas fed in-phase. Practical construction notes include recommendations for vertical descent of the matching section, sealing the coax junction, providing strain relief, and winding a coaxial choke coil to mitigate common mode current. The resource also presents dimensions for double-size (204 ft) and half-size (51 ft) G5RV versions, along with their corresponding matching section lengths for various line types, making it a versatile reference for hams considering this classic wire antenna.

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

An interesting homebrewed gamma match feed for a Halo Antenna

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

Shortened vertical antenna for 40 meters band an homebrew project

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

This article document a 2 element half wave collinear J-Pole antenna by KC9EOT and KB8OJH

A 9:1 voltage unun using a T-200-2 powdered iron toroid core to feed a long wire multiband antenna.

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.

Calculating Antenna Wind Load

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.

K0EMT mobile antenna mast mount

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

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.

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

An active receiving antenna for 10 KHz to 20 MHz, a very small sized antenna with excellent performances in noise to signal ratio.

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.

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

Find the best placement of a mobile antenna

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

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

4 elements Yagi antenna for 28 MHz

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

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

A page dedicated to antenna coil home brewing and coil design by VE6WZ

Drawing and plan for an HF magnetic loop antenna

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

An easy to make, cheap, no trap, multiband wire vertical antenna by PA1M

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

Homebrew a compact yagi antenna for 14 Mhz suitable for those with small plots based on a design by AB4GX

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

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

A simple VHF vertical aerial for the home station

A folded dipole using twin lead By W8HDU

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

Magnetic Loop antenna for broadcasts band reception

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

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 home made yagi antenna featuring 6db forward gain and 22 Db front back

Manufacturer of single band and multiband transceiver bandpass filters for HF. High pass filters, two radoi headphones mix and switch, 6 meter portable antenna, antenna remote switching and steering.

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

A project of a bobtail-curtain antenna for 10 MHz

Luksa industries design and manufacture mechanically operated aluminum telescoping masts and telescoping tripods to support communications and military antennas

A VHF UHF 5+5 elements yagi antenna by CE4WJK

Loop antenna picture gallery

Alford slot antenna for 1.3 GHz to 2.3 GHz.

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