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This calculator is designed to give the vertical length of a quarter-wave ground plane antenna, and the length of each of the four radials for the selected frequency you have entered

A DIY guide to build your own compact multiband HF antenna based on the G3TXQ version using a 1:4 balun. This article includes the full part list and instructions to assembly, including the center plate.

An home made slim jim antenna for 2 meters band by VU2TQC

This PDF document details the construction of a **70 MHz** Big Wheel antenna, a horizontally polarized omnidirectional array. The design utilizes three full-wave loops, each approximately **2160 mm** in diameter, arranged in a triangular configuration. The resource provides mechanical dimensions for the antenna elements and a comprehensive bill of materials, specifying component quantities and types, such as M8 stainless steel bolts, 15x15x1.5 mm square aluminum tubing for spacers, and 8 mm aluminum rod for the arcs. The central hub is constructed from two 160x160x8 mm aluminum plates, with four 40 mm long polyamide insulators supporting the radiating elements. The feed system incorporates a 50 mm diameter aluminum pipe for mounting and a matching stub constructed from a 120x20x2 mm aluminum sheet, connected via M8x10 mm bolts. The resource includes a diagram illustrating the mechanical dimensions and assembly points, including the N-connector fixing point and the center conductor attachment. The project was published on May 25, 2011, by Peter OE5MPL and Rudi OE5VRL. DXZone Focus: PDF | 70 MHz Big Wheel | Mechanical Dimensions | **2160 mm** loop diameter

K0GKJ project of a copper tube slim jim antenna for two meter band

Article describing how to homebrew a yagi antenna for 50 MHz, includes plans for a four and five elements yagi beam and details how how match impedence with a gamma match

Some basic antenna information for the newcomer

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

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.

Homebrew GMRS 3 Element Yagi yagi for 462-467 MHz

Limiting static surges on dipoles, verticals or end fed antennas

Delta loop antennas for 40 meters plans and comparison of some models

Antenna for limited space, made from 24AWG wire helically wrapped around the top element of a 3-element cane pole, is basically a fully-loaded vertical and performance are limited and should represent the last resort for extreme cases.

The HF horizontal loop has been around for many years now. This article includes a YouTube video and discusses the reasons for looking at this antenna, its design, and its installation. There are some on-air comparisons against three regular double bazooka (coax) dipoles and the Par SWL End-Fed antenna.

Magnetic Loop Antennas for The Radio Operator with Limited Space, a two part series of articles on how to construct a magnetic loop antenna, including directions on selecting high voltage tuning capacitor

G4ILO compares popular antennas for 2 metre band handhelds so as to see how much you lose using a small inconspicuous antenna or how much you gain by using a long antenna.

This circuit enables fair copy of strong 444 MHz signals, off a local repeater, using a 2m rig and a 1/4λ 70 cm indoor ground plane antenna.

Operating magnetic loop antennas requires careful consideration of RF safety, particularly regarding near-field magnetic field intensity. This resource presents calculations for magnetic field strength (H-field) at various distances from a magnetic loop, emphasizing that the H-field is significantly higher than the E-field in the near-field region due to the inductive nature of the radiating element. It provides specific formulas and examples for determining safe operating distances based on power levels and loop dimensions, crucial for compliance with RF exposure limits. The analysis compares calculated H-field values against FCC and ICNIRP maximum permissible exposure (MPE) limits for controlled and uncontrolled environments. It demonstrates that even at QRP power levels (e.g., 5W), the H-field can exceed MPE limits within a few feet of the antenna, necessitating greater separation distances than often assumed for electric field considerations. The practical application of these calculations helps amateur radio operators configure their stations to ensure personnel safety and regulatory compliance when deploying compact, high-Q magnetic loop antennas.

Testing performances of indoor antenna. A comparison of a magnetic loop antenna vs a classic wire dipole done using wsprlite on 30 meters band.

A nice post on Make: on homebrewing a multiband antenna for amateur radio portable operations

May 2015 Radcom Article on common-mode chokes that can be used for control cables, phone lines, but mostly on typical HF antenna systems. This article explain what common mode chokes does, why you meay need one, properties common mode chokes should have, how to build and measure performances.

Stop common-mode current when transmitting with an end-fed antenna. Unbalanced antennas are very prone to currents on the outside of the coax.

A portable VHF yagi antenna designed for SOTA operations based on the orignal DK7ZB concept.

Slot cubes are folded skeleton slot antennas with widened, folded dipoles bent into a cube to reduce size. QST Article 12 2019

Notes on how to build an inverted V wire antenna with lenghts for all HF bands from 160 mtrs to 10 mtrs

An comprehensive article on 40 meters antenna comparing vertical height to the resulting gain

The configuration of this antenna is a triangle with apex in the top of a very tall tree. The antenna is fed at a bottom corner using 450 ohm ladder line.

A multiband trapped end-fed antenna can cover 20 30 40m bands. An option for portable sota operations were weight end simplicity are essential

An home made end fed half wave antenna with a tuner box by NG0R

A vertical antenna project for the 7MHz made with some spare parts. Based on a broken 20 foot fishing pole, it is based on a good ground system made with radials and a capacitive hat done to increase the global radiation resistance of the antenna. A custom loading coil is also included in this project to perfectly tune the antenna to the CW portion of the 40 meters band.

Demonstrating the construction of a short dipole antenna tailored for the 60 meter band, this resource provides detailed instructions for radio enthusiasts with limited space. The design incorporates inductive loading using two inductors (L1/L2) made from PVC tubes, allowing for effective operation on 5 MHz. The antenna consists of 12 meters of wire, divided into four sections, with specific dimensions and materials outlined for optimal performance. Results from users indicate that this antenna can significantly enhance DXing capabilities on the 60 meter band. Feedback from operators suggests that while the design is effective, adjustments may be necessary based on individual setups, such as coil diameter and wire gauge. Many users report successful construction and operation, with some experimenting with variations to improve resonance. The practical application of this antenna design has led to successful contacts and improved signal quality, making it a popular choice among 60 meter band operators.

An economical dipole for simple QRP HF homebrew rigs

Mounting antenna close each other. Distance calculations and tips on setting up antennas by KB9VBR

A collection of drawings of most popular wire antennas for hf ham radio bands

The Icom AH-4 autotuner operates efficiently across multiple HF bands, providing seamless automatic tuning for antennas from 3.5 MHz to 54 MHz. Its robust design allows for outdoor installation, making it suitable for field operations and fixed stations. The unit interfaces with Icom transceivers via a control cable, enabling automatic band switching and tuning. The AH-4 is capable of handling up to 120 watts of RF power, ensuring compatibility with most amateur radio setups. Its weather-resistant casing and compact form factor make it a versatile choice for operators requiring reliable performance in diverse environments. Field tests demonstrate the AH-4's ability to maintain low SWR across its operational range, enhancing signal quality and transmission efficiency. Compared to manual tuners, the AH-4 offers significant time savings and ease of use, particularly in rapidly changing band conditions. Its integration with Icom radios simplifies operation, eliminating the need for manual adjustments. The autotuner's performance is consistent with other high-end models, providing a cost-effective solution for amateur operators seeking dependable tuning capabilities without sacrificing performance.

An end-fed-half-wave antenna matcher project based on a FT-82-43 core with a 100 pF and 45 pF capacitor in parallel

This kind of antenna has grown in popularity over the last years because it gives you a decent performance and triband capabilities. But its 50 MHz design is far from optimal. Here you can learn how to improve its 50 MHz performance in a very easy way.

The **TransWorld Antennas TW2010 Traveler HF Portable Vertical Antenna** assembly video provides a visual walkthrough for deploying this popular portable HF antenna. It details the step-by-step process, from unpacking components to final setup, which is crucial for operators preparing for field day operations or DXpeditions. The video focuses on practical aspects, showing how to connect the various elements and secure the antenna for optimal performance. Operators often seek clear assembly instructions for portable antennas like the TW2010 to ensure quick and correct deployment in diverse environments. This visual aid helps clarify potential ambiguities found in written manuals, illustrating the proper handling of the antenna's radial system and telescopic elements. The video serves as a valuable resource for those aiming to achieve efficient operation with the **TW2010 Traveler** in a portable setting. Understanding the assembly sequence can significantly reduce setup time and prevent common errors encountered during initial deployments.

Make and automatic antenna tuner based on Arduino and using economic card. This ATU Project can be installed outdoors and controlled remotely by an rs485 link

How to calculate range for a VHF antenna with a simple formula and how to increase VHF coverage.

A dual band portable inverted V antenna for 80 and 40 meters band with dimensions for other bands and several assembling instruction

Demonstrates the _RoMac Automatic CW Identifier 2012_ software, a Windows application designed to automate station identification and provide a tuning pulser. It can send CW identification via a sound card's audio output or by keying a radio's manual CW jack using a serial port's DTR line. The software also supports CAT commands for various Kenwood, Yaesu, Flex, and Elecraft radios, enabling automatic mode and frequency changes for ID transmission. It integrates with USB audio-capable radios like the Icom 7300 and Yaesu FT-991, simplifying connectivity with a single USB cable. The application features a fully programmable interface, adjustable CW speed from **5 to 35 WPM**, and ID intervals from **5 to 30 minutes**. The integrated "Pulse Tuner" function allows for safe amplifier and antenna tuner adjustments by sending short audio tones or rapid CW keying, with an adjustable duty cycle from 1% to 100%. It offers compatibility with a wide range of transceivers and amplifiers, and a schematic for a basic sound card interface is included for users without existing setups.

Comment on W5DXP 2011 coil measurement experiment

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

A moxon antenna for the 50 MHz build with 19 feet of 14 AWG copper wire, and based on a set of PVC pipes. This is an easy to build project that will give you an efficient directional antenna on 6 meters band with low SWR on more than 1 MHz bandwidth.

Gold Line, a manufacturer, provides a range of professional audio test and analysis equipment, including specific products like the **ZM1 Impedance Meter**, which is relevant for amateur radio operators needing to characterize antenna systems. The site also lists various noise sources and microphones, such as the TEF04 Mic, indicating a focus on audio signal integrity and measurement. The resource details contact information for repairs, calibration, quotations for specific products like the ZM1 and ZM1P, and technical support, with distinct email addresses and phone numbers provided for each function. This structured contact approach facilitates direct engagement with the appropriate department for specific inquiries. Operational changes effective March 1, 2019, are noted, directing users to VLDESIGN for repair and calibration, and to Partha Chen for ZM1/ZM1P quotations. Louis Pittsley is designated for technical support, with a general inquiry phone number also available, outlining the company's support infrastructure.

An article about the Rybakov 806 Vertical antenna. The classic Rybakov configuration is a 7.6m or 8m ( aprox 25 or 26 feet) wire fed through a 4:1 UNUN

IZ5CML, Enrico Giannerini, obtained his amateur radio license in 1998, achieving DXCC contacts with all entities over 18 years of activity. His station, located in Empoli, Tuscany, Italy, focuses on HF and 50 MHz operations, primarily using SSB, CW, and some RTTY. He emphasizes direct radio communication, preferring "human modes" over digital modes like FT8/4, which he views as detaching the operator from the signal. Enrico's operating interests include DXing, IOTA activations, and major HF contests, where he has participated both individually and with teams like IQ5LV and IO5O. Notable activations include Sao Miguel and Flores (CU8, EU-089) in the Azores in 2005, and Antiparos and Paros (EU-067) in Greece in 2006 and 2014. He also contributes to the Hamradioweb forum, promoting good operating practices and publishing the monthly "Dxschedule" for upcoming DX and contest activities. The website includes a blog with articles on DX, ionospheric propagation, and antennas, reflecting his long-standing passion for radio, sparked by the 1980s film "La Tenda Rossa" and years as an SWL.

An article that explain with simple concepts and basic theory the correct usage of antenna tuners. It covers some aspects of common questions newcomers have on what antenna tuners are for, and what antenna tuners will never do.

Homebrewing a Lightweight linked dipole HF antenna for portable SOTA operations