Search results

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.

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

A UHF antenna for satellite reception. Anntenna mast is in wood, made with two aluminium rods

YF1AR multiband vertical antenna, based on orginal concept by VE7BS. Consist of 6 vertical elements and 6 base radials with a single 50 Ohm feed line.

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

You can make your own 2-meter "rubber duckies" that will likely perform much better than many commercial units.

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.

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

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

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

Drawing and plan for an HF magnetic loop antenna

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

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

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

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.

A VHF UHF 5+5 elements yagi antenna by CE4WJK

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

An HF multiband trapped antenna in french

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.

This article describes a simple Inverted L antenna for the HF bands designed to work on 80m, 40m, 30m and 20m

KA9LXP's HF antenna mast page

Centre fed half wave dipoles make great, simple and effective antennas for the HF bands. Sometimes however, the centre feed is not ideal. This great project will improve the overall antenna performance.

Located in southern Ontario Canada, supplier for HF VHF antenna kits, aluminium tubing, portable j-pole antennas, lightning suppressors, connectors and adapters

An home made Butternut HF9V clone antenna by OH2GVB

An easy portable VHF antenna to build for ARES - RACES work is the 300 Ohm Twin Lead JPole antenna

a methodology for connecting multiple LF/MF/HF receivers to a single antenna via readily available and inexpensive 75-ohm TV cable.

VHF UHF diplexer by G8MNY

This antenna analyzer measures complex impedance over the 1.6 - 33 MHz HF spectrum

This article explores the performance of an unloaded elevated vertical, base matching and feed line as a multi-band HF antenna system.

Development of the Slim Jim antenna for HF

This article describes the characteristics of the Windom antenna and shows the results of several simulations made with MMANA-GAL, covering models optimized for the 20 m, 40 m and 80 m bands.

A 5 band two element quad antenna working from 20 to 10 meters using hardware-store parts or modifying an existing commercial triband quad by KC6T

The Resonant Feedline Dipole (RFD) HF antenna design utilizes a single piece of coaxial cable and a stranded wire section, forming a 1/4-wavelength radiator. This configuration, based on a 1997 ARRL Handbook design (page 20.17), functions by RF traveling on the inside of the coax shield and returning on the outside, creating the second half of the dipole. A choke wound into the feedline prevents RF current from flowing back down the feedline. Construction details include using RG-58a/u coax for a 75m version, with a 1/4-wavelength section of stranded wire soldered to the center conductor. The document provides choke dimensions for RG-213, RG-8, and RG-58 coax across 3.5 MHz to 28 MHz, specifying cable length and number of turns. Dipole dimensions are also tabulated for frequencies from 3.6 MHz to 28.4 MHz, listing overall length and individual leg lengths. Field tests included deployment near Bryson City at 5 feet off the ground and as a sloper during WCARS Field Day in Asheville, yielding successful local and regional contacts.

Using our components you can build a rotating tower with greater capability than 3-4 static towers. A rotating tower allows common rotation of HF stacked arrays, VHF and UHF arrays, and antennas mounted at optimum heights. Component design also allows tower shunt loading and end support for wire antennas

This article explores the performance of an unloaded vertical as a multi-band HF antenna.

RFAC Solutions specializes in providing a range of RF components, including various connector types, cable assemblies, attenuators, and filters. Their product line features common connector standards such as SMA, BNC, TNC, N-Type, MCX, and MMCX, essential for reliable RF signal paths in amateur radio and commercial applications. The company also offers high-power VHF amplifiers, catering to needs for signal boosting in specific frequency ranges. Their offerings extend to dust caps and adapters, which are crucial for maintaining the integrity and versatility of RF systems. The focus on supplying components from South Korea suggests a commitment to specific manufacturing standards and supply chain practices. This resource details a vendor's product scope, useful for hams sourcing specific parts for shack builds or antenna projects. Jeff is listed as a contact for inquiries.

A scanned PDF of this interesting book on HF Dipole antennas published by Stanford Research Institute

A remotely tuned 80m to 10m wire vertical antenna

Optimizing a G5RV or ZS6BKW multiband wire antenna for HF operation often involves addressing common SWR issues and understanding feedline characteristics. This resource chronicles the construction and performance evaluation of a G5RV, initially built for 80m, 40m, 15m, and 10m bands, by a newly licensed Foundation operator. The author details the selection of materials, including 3.5 mm stainless steel wire for the doublet arms and enameled copper wire for the open-wire feeder, and the initial decision to omit a balun based on common online information. The narrative highlights the initial disappointing performance, characterized by high receive noise and poor signal reports on 80 meters, despite the transceiver's internal ATU achieving a 1:1 match. This led to experimentation with a coax current balun and further research into G5RV myths, such as SWR claims and the necessity of a balun. The author then describes modifying the antenna to the ZS6BKW configuration, which involves specific changes to the doublet and feedline lengths, and integrating a 1:1 current balun wound on a ferrite toroid. The modifications resulted in improved reception and transmit performance across the bands.

The NCDXF/IARU International Beacon Project operates a worldwide network of 18 high-frequency radio beacons, continuously transmitting on 14.100, 18.110, 21.150, 24.930, and 28.200 MHz. These beacons, initially launched in 1979 with a single station and expanded to the current 18-beacon system in 1995, provide reliable signals for both amateur and commercial users to assess current **ionospheric propagation** conditions. The system's design, construction, and operation are managed by volunteers, covering hardware and shipping costs. The resource details the evolution of the beacon network, including the transition from Kenwood TS-50s transmitters to Icom IC-7200 radios with a new controller design implemented in 2015. It explains how listening for these 100-watt signals, transmitted to vertical antennas, allows operators to determine band openings and optimal propagation paths globally. The content also references three QST articles providing historical context and technical specifics of the beacon project. Practical information includes methods for identifying transmitting beacons via a schedule or specialized software like FAROS and Skimmer, which integrates with the **Reverse Beacon Network** for automated monitoring.

A Unique VHF Antenna with gain over a J-Pole Jose I. Calderon, DU1ANV

For amateur radio operators engaged in **radio direction finding** (RDF) and **transmitter hunting** (T-hunting) activities, this resource provides a catalog of printed circuit boards (PCBs) for constructing various DF and foxhunt-related projects. The offerings include PCBs for 80-meter fox transmitters and receivers, UHF fox transmitters with audio recording capabilities, and several designs for general-purpose radio direction finders. Specific projects like the "Simple 80M ATX-80 Transmitter" and the "N0GSG DSP Radio Direction Finder" are listed, along with attenuator boxes and specialized components for Doppler DF systems. The catalog details PCBs for projects published in prominent amateur radio magazines such as *73's*, *CQ*, *QST*, and *PE*, indicating their origin and design pedigree. For instance, the "Montreal Fox Controller" is sourced from the *Homing-In* column by Joe Moell, K0OV. The resource also lists components for advanced Doppler DF systems, including main boards, LED display boards, and antenna switch boards, with options for programmed PIC microcontrollers. Pricing for each PCB is provided, allowing hams to acquire the necessary components for their DIY RDF endeavors.

Unlocking the full multiband potential of the 225 Ohm elementary radiator in a folded monopole, dipole-like or turnstile layout, by Francesco Errante

Demonstrates the construction of a 144 MHz turnstile antenna, detailing its design for omnidirectional, horizontally polarized VHF operation. The resource outlines the physical dimensions and materials required, including specific lengths for the radiating elements and the use of _RG-58_ coaxial cable for phasing. It covers the assembly process, emphasizing the critical spacing and connection points to achieve the desired radiation pattern and impedance matching for the _2-meter band_. The article presents measured _SWR_ performance across the 144-146 MHz segment, showing a low SWR of 1.2:1 at 144.5 MHz, which is suitable for general VHF use. It compares the turnstile's performance to a 9-element Yagi, noting the turnstile's advantage in providing consistent signal strength from all directions without requiring a rotator. Practical application for local FM simplex and repeater operations is implied, offering a simple yet effective antenna solution for fixed or portable stations.

17-Element Very High Frequency/Ultra High Frequency Log Period Dipole Array

VK3YE magnetic loop antenna plan that cover 7 Mhz to 20 Mhz and shortening loop can work on 21 Mhz.