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Marshall G. Emm, N1FN, meticulously examines iambic keying, dissecting its historical introduction in the late 1950s with transistorized electronic keyers and its purported advantages. The resource defines keying systems, electronic keyers, and various paddle types, including single-lever and dual-lever paddles, clarifying the distinction between iambic keyers and the iambic sending technique itself. It details the two main types of squeeze keying: true squeeze for alternating dot-dash strings and character insertion for specific elements within a character. N1FN critically evaluates the actual efficiency gains of iambic keying, referencing Chuck Adams, K7QO's, keystroke analysis. While a straight key to bug transition yields a 34.1% reduction and a bug to non-iambic keyer offers 16.1%, iambic keying provides only an 11% theoretical improvement. However, considering typical QSO text and Morse code's inherent optimization for common letters, the practical efficiency gain is estimated at a modest 4-6%. The article also highlights how iambic keying's reliance on precise timing gates can impose a speed limit, making it less effective above 40 WPM, where many operators revert to non-iambic methods or single-lever paddles.

This calculator is designed to give the critical information of a particular beam antenna, in this case a three element Yagi, for the frequency chosen.

A presentation of the Yagi Antennas, and other interesting tid-bits by Brian Mileshosky. The document provides an in-depth exploration of the Yagi-Uda antenna, detailing its historical development, design principles, and performance characteristics. Originally described in the 1920s, the Yagi antenna features a driven element and parasitic elements, including reflectors and directors, which collectively determine its behavior. The document highlights how element lengths, diameters, and spacing influence gain, impedance, and directivity. It also discusses the antenna's reciprocal nature and presents data on typical gain values for various element configurations. Additionally, the text covers practical considerations, such as the construction of a "Tape Measure Yagi" for amateur use, and touches on related antenna types like dipoles and their application in Near Vertical Incident Skywave (NVIS) communication.

Indoor setup of a two element SteppIR antenna

A Six element antenna for the 50 MHz Amateur Radio Band v4 by DF9CY

An easy to build and extremely high performance antenna, works perfectly on all HF bands 3.5-28 MHz with some compromises, it is basically an half wave dipole for 40-80 meters, an LC circuit or trap 40 meters allows you to use a single radiating element.

This online project guide details the construction of a homebrew boom microphone system. It details the assembly of a microphone shell from a 3/4" PVC pipe section and an end cap, requiring a drilled hole for a snug fit of the electret or condenser mic element. The internal wiring schematic specifies a **2.2 K** resistor and a **47 uF** polar capacitor for signal conditioning, with a circuit diagram provided for integration with IC-706 series transceivers. The guide outlines the use of CAT-5 cable for internal connections, incorporating strain relief at the rear of the mic shell, and an inline 3.5 mm jack to facilitate an external _PTT_ line, designed for a foot-mounted switch. Further construction involves fabricating a microphone shock mount from a 2-inch PVC connector, detailing the creation of four "fingers" and the insertion of screw-eyes for attaching elastic bands, which are twisted 180 degrees for tensioning and vibration isolation. A foam wind screen is also incorporated into the microphone assembly, secured with adhesive. The boom arm itself is repurposed from an articulated architect lamp, with the original lamp assembly converted into a **60 watt** resistive load for testing power sources. Microphone cabling is secured to the boom arm using wire ties, ensuring sufficient slack at hinge points to maintain articulation. The boom base is mounted to a bookshelf, requiring specific positioning to achieve proper microphone placement in front of the operator. Performance evaluation of the microphone system is conducted through on-air audio signal reports from other amateur radio operators. DXZone Focus: Online Project Guide | Boom Microphone Construction | Electret Mic Element | PTT Line

Operating the AO-51 amateur radio satellite with a handheld transceiver (HT) presents a practical entry point for newcomers to satellite communications. This resource details the necessary steps and considerations for making basic contacts, focusing on accessible equipment. It covers fundamental concepts such as _Keplerian elements_ for satellite tracking and the importance of understanding Doppler shift effects on both uplink and downlink frequencies. The tutorial outlines a straightforward approach to satellite passes, emphasizing the use of readily available gear. It provides insights into antenna orientation and timing for successful two-way communication. The content aims to demystify satellite operation, enabling operators to achieve their first **AO-51** contacts with minimal specialized equipment. Key aspects include frequency management and basic operational techniques.

Constructing a compact directional antenna for the 17-meter band, this resource details the build process for a Moxon rectangle, a two-element Yagi variant with folded-back elements. It covers the antenna's evolution from the _VK2ABQ beam_ and provides specific dimensions for a version built using fishing pole whips. The content includes a discussion of the antenna's radiation pattern, feedpoint impedance, and its inherent front-to-back ratio, which is often superior to a standard two-element Yagi. Practical considerations for element spacing and material choices are also addressed, alongside a visual representation of the antenna's physical layout. Performance data presented includes a comparison showing the Moxon rectangle's **2.5 dB gain** over a half-wave dipole and a front-to-back ratio of **20 dB**. The resource also touches upon the antenna's relatively wide bandwidth for a two-element beam and its suitability for portable operations due to its compact footprint. It offers insights into optimizing the design for specific operating conditions and discusses the advantages of its lower take-off angle compared to omnidirectional wire antennas, making it effective for DX contacts on the 17-meter band.

This version of the broadband hexbeam is based on the work of Hunt G3TXQ, HB9MCZ, and Shoemaker K4KIO. EZNEC model is based on a wider element spacing than the version published in QST by K4KIO

A portable VHF/UHF portable 6 element Yagi antenna project by OH2GVB

The dipole shown in this document is installed in an inverted Vee configuration, with two leg elements on each side held parallel to each other by 21cm spacers. The upper leg is for 40m and the lower leg for 20m. The spacers are made of 7mm plastic garden hose support for garden sprayers cut to 21cm.

Constructing a directional antenna for the 6-meter band (50 MHz) can significantly improve signal strength and reduce QRM during local ragchews or **Field Day** operations. This project details the assembly of a Moxon rectangle antenna, known for its compact size and respectable gain, making it a practical choice for portable or fixed station use on the magic band. The design utilizes readily available materials such as 14 AWG copper wire for the radiating elements and PVC pipe for the frame, ensuring an inexpensive build. The article provides specific dimensions and construction steps, allowing radio amateurs to replicate the antenna with confidence. It emphasizes achieving a low **SWR** across a bandwidth exceeding 1 MHz, crucial for efficient power transfer from the transceiver. Performance characteristics include a reported 5.5 dBi gain and a front-to-back ratio of 20 dB, offering effective directivity. The project also highlights the antenna's suitability for Field Day, where quick deployment and reliable performance are paramount for maximizing contacts.

2-Element-12,5-Ohm-Yagi with 0,40m-Boom complete description of all details for building this Yagi and stacking to an array

A 2m band Moxon antenna design is presented, centered at 145.2 MHz, with dimensions derived from Moxgen software. The design features a calculated 6 dBi gain, an 80-degree beamwidth, and an impressive 43 dB front-to-back ratio with minimal back lobes, concentrating RF energy in the forward direction. The antenna is balanced to 50 Ohms, facilitating direct feed. SWR sweep data from 144 MHz to 146 MHz demonstrates a near 1:1 SWR at the center frequency, maintaining healthy SWR values across the entire 2m amateur band. This performance is comparable to a 3-element Yagi, yet the Moxon offers advantages in compact size and ease of mast mounting, making it suitable for various operating environments.

The construction principles for open-sleeve elements in antennas

Three Yagi antennas for the six meters band by 9A7PJT. Include a 4 element yagi, a custom design 4 element, and a 5 element yagi with antennas pictures and design.

This article is about a 4 element yagi VHF antenna designed to be easy to be assembled and suited for portable operations

5 Elements 12,5 Ohm Yagi with a 6m Boom

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.

This 6 meter 2 element yagi antenna is simple, compact and effective antenna for 50 Mhz. The design antenna was optimized with AO for best match to 50 ohms, no matching network. A choke balun is recommended to decouple feedline currents.

A delta loop antenna for 20 meters band designed with MMana with a tuning system made in a classic stub configuration

Wideband receiving phased arrays with small electric or magnetic active wideband elements are discussed in details. Practical results and examples are given.

This web article details the construction of a 4-meter band coaxial dipole antenna, designed for operation between **70.000 MHz and 70.500 MHz**. The resource provides a bill of materials and step-by-step assembly instructions for a half-wave dipole constructed from _RG-58_ coaxial cable. The design specifies a direct 50 ohm feedpoint impedance, eliminating the need for an external matching network. Construction photographs illustrate the stripping and soldering processes for the coaxial cable elements, ensuring proper electrical connection and physical integrity. The article includes specific dimensions for the radiating elements, derived from calculations for the 70 MHz band. The project outlines the physical dimensions required for resonance at 70 MHz, with the outer braid forming one half and the inner conductor forming the other. The feedline connection is directly to the coaxial dipole's center, maintaining a 50 ohm characteristic impedance. While the article does not present SWR plots or VNA sweeps, it focuses on the mechanical construction and dimensional accuracy for achieving a functional 4-meter dipole. The design is intended for fixed station use, with no specific mention of polarization or height above ground, but implies a standard horizontal orientation for dipole operation. DXZone Focus: Web Article | 4m Coaxial Dipole | Construction Guide | 50 ohm Feed

1.5 dB of matched line loss can be calculated for a given transmission line using this online tool, which employs a model calibrated from empirical data. The calculator allows radio amateurs to input specific transmission line types, such as _RG-8_ or _RG-58_, and then determine the expected signal attenuation. This is crucial for optimizing antenna system efficiency and understanding power delivery to the radiating element, especially for HF and VHF operations where feedline losses can significantly impact performance. Beyond matched loss, the calculator also provides an estimate for mismatched loss if the Standing Wave Ratio (SWR) is specified. This feature helps operators quantify the additional power loss due to impedance discontinuities between the transceiver, feedline, and antenna, which is a common concern in amateur radio installations. Accurate loss calculations are vital for effective station design and for predicting actual radiated power. The tool's utility extends to various operating scenarios, from fixed station setups to portable deployments, aiding in the selection of appropriate feedline lengths and types to minimize signal degradation. Understanding these losses is a fundamental aspect of maximizing the effectiveness of any amateur radio antenna system.

Six meters is a great band for home built Yagis. The elements are reasonably small, but not so small that building tolerances are critical. With careful construction and detailed instructions, it is certainly feasible to build no-tune Yagis up to 432 MHz.

An article describing how to homebew a VHF 4 elements Yagi antenna.

An interesting presetnation full of usefull tricks to correctly design and build 23 cm Yagi using simple tools. The basic design of the antenna presented in this document is taken from the original DL6WU Yagi Design published in 1982

A 50.200 MHz Moxon antenna for the 6-meter band is detailed, providing practical construction guidance for amateur radio operators. The design utilizes 3/4" aluminum angle stock for the elements, joined with wood molding and 1/4 x 20 hardware. Key components include an SO-239 connector for the feedpoint and a **choke balun** made from coiled RG-58 coax, ensuring proper impedance matching and minimizing common mode current. The antenna measures approximately 29 inches deep by just under 7 feet long, making it suitable for portable operations. Specific dimensions, based on **Cebik's nomenclature**, are provided for the driven element and reflector. The resource also offers modeling hints, suggesting an effective element diameter of 1 inch for software simulations and emphasizing element sizing based on corner screws rather than end-to-end measurements.

Pictures, design plan and description of a 5 element yagi antenna for the 4 meters band by 9A7PJT

The F5GIT blog documents the amateur radio pursuits of Tony, F5GIT, offering insights into his DXpedition experiences and contest operations. It presents detailed accounts of his participation in events like the _CQ WW DX Contest_ and the _IARU HF Championship_, often including specific callsigns worked and operational strategies employed. The resource covers various aspects of station setup, antenna configurations, and radio equipment used for achieving contacts across different bands. Content includes discussions on antenna performance, such as a **2-element Yagi** for 10/15/20 meters, and operational challenges encountered during remote or portable setups. The blog also serves as a personal log, chronicling significant QSOs and providing a historical record of his amateur radio journey. It details specific locations operated from, like _Île de Ré_, and the unique challenges presented by such environments. Furthermore, the blog provides practical information on optimizing station efficiency and maximizing contact rates during high-intensity operating periods. It reflects a dedicated approach to improving radio skills and contributing to the global amateur radio community through active participation and sharing experiences.

4x14-(28) Element Cross-Yagi 28-Ohm DK7ZB

YT1VP Yagi antenna for 6 meters

The resource provides an interactive map interface for locating amateur radio license holders across the United States. Users can input a _callsign_, _gridsquare_, zip code, or street address to center the map, which then dynamically populates with station markers. This functionality allows for precise geographical searches, revealing the distribution of hams within specific areas. Upon initial search, the map renders with adjustable zoom and pan capabilities. A key feature is its automatic reload mechanism: after two seconds of inactivity, the map updates to display stations within the newly viewed area. This ensures that the displayed data remains relevant to the user's current focus, whether exploring a densely populated urban center or a more remote region. Further interactive elements include clickable gridsquare labels, which re-center the map, and a "Show gridsquares" checkbox for toggling grid line visibility. Clicking on individual station markers reveals a popup containing the licensee's name and address information, making it a practical tool for geographical station identification.

A page describing all element of a weather statio for NOAA weather satellite image reception

Plans for building your own 3-element beam for use on 6m.

A home made 4 element yagi antenna that can be easily adapted for 10 meter band

The resource examines the operational characteristics and potential of Moxon Yagi antennas, drawing insights from Les Moxon's work and subsequent NEC modeling. It presents simulated current distributions and radiation patterns for a 40-meter Moxon, comparing its performance against a standard 2-element Yagi on the same band. Specific data points include forward gain, front-to-back (F/B) ratio, and feedpoint impedance, which are critical parameters for antenna design and optimization. Further analysis extends to a 20-meter Moxon, detailing its gain, F/B ratio, and SWR bandwidth across the band. The discussion highlights the Moxon's compact footprint and its ability to achieve respectable performance metrics, making it a viable option for hams with limited space. The content provides a technical assessment of the Moxon's advantages in terms of pattern purity and impedance stability compared to other compact directional arrays. The article also touches upon the practical considerations for constructing and deploying Moxon antennas, emphasizing the trade-offs between physical size and electrical performance. It includes graphical representations of antenna currents and radiation patterns, offering visual aids to understand the theoretical concepts discussed.

A fun little project I did over a couple of days was making this little 6 element yagi for 70cm. There are so many designs and ways one can do this so after some reading of different designs and measurements

A compact Yagi with bent Driven Element. Worlds smallest yagi that did EME QSO

YU7EF 8 elements yagi antenna for 4 meters band

23cm 1296 MHz Field Day Yagi Construction, a 26 element conventional-style design. Article with several pictures and detailed homebrewing instructions

Explains the proper formatting of international addresses on postal items, a critical aspect for ensuring successful delivery of QSL cards. It details how the country of origin dictates the destination country's name format, while the destination country's postal authority governs the remainder of the address. The resource highlights _Universal Postal Union_ (UPU) regulations, specifically Article RL 123.3.3, which mandates the use of roman letters and Arabic numerals for clarity. It provides practical examples, such as an item from Great Britain to the United Arab Emirates, illustrating the need for dual-language addressing. The guide also clarifies the separation of elements for proper transmission versus local delivery, ensuring that the destination country name is clearly marked in capital letters and preferably in an internationally recognized language to facilitate transit, preventing misdirection and ensuring a **99%** delivery rate for QSLs.

Rotatable Antenna with Phased Elements based on the orignal design concept of HB9CV antennas, is considered to have an higher gain than standard quad antennas. The Swiss Quad Antenna does not need any spreader or boom.

The calculator designs the Yagi-Uda antenna based on the DL6WU model with boom correction, following the G3SEK-DL6WU method. It optimizes the antenna for maximum gain and allows adjustment of passive elements without affecting SWR. DL6WU antennas are known for their high gain, minimal sensitivity to nearby objects, and stable performance in various weather conditions.

Article about a high-gain, narrow-band version feature 7.15 dBd and a F/B 13dB with details on how to setup in array mode

A multiband Fan Dipole that works on 40 20 15 meters band, making a folded dipole for 7 MHz band and additional element for the 21 MHz and 14 MHz

A Six-element Yagi Beam for 6 Meter by W1JR proiddes a power gain of 10.2 dB over a dipole it is built on a 24 foot long boom

SDR Project for a compact amateur radio software defined radio trasceiver covering HF bands all mode. Website includes schematics, element PCB, pictures, movies, firmware and elements bom.