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This antenna was designed for the CQ WW CW 2009 at EA8URL. All elements are made out of fishing rods with an insulated copper cable fixed on the rods by cable ties. Both fishing rods and cable are UV resistant.

This article describes the details of the design, which can be easily scaled for just about any HF band. The antenna described in this article is for the 20 meters band.

Presents Eagle Stainless Tube & Fabrication as a certified distributor specializing in various tubing products essential for antenna construction and other amateur radio projects. It details their offerings, which include aluminum tubes in fractional, metric, and heavy wall specifications, alongside stainless steel bar stock in round, square, and flat profiles. The resource highlights the availability of a diameter sizing chart and direct contact options for specialists, indicating a focus on providing specific material dimensions and expert support for custom fabrication needs. The company emphasizes its role as a supplier of raw materials, crucial for hams engaged in DIY antenna builds or structural components for their shacks. Their inventory supports the precise mechanical requirements often encountered in radio frequency engineering, where material strength, weight, and corrosion resistance are critical design factors for outdoor installations. The site primarily serves as a product catalog and contact point for sourcing specialized metal tubing and bar stock, providing technical specifications and material grades relevant to robust amateur radio infrastructure.

Design and build a 6 meter 2-element Moxon antenna mostly from available aluminum tubing and angle stock.

The Buddipole Deluxe, a portable HF/VHF antenna system, receives a practical assessment from IW5EDI after a month of field use. The author, constrained by antenna restrictions, highlights the system's crucial role in enabling portable operations, even managing sporadic digital activity from a balcony. Direct comparisons to a fixed 3-band dipole reveal surprisingly comparable signal reports on 15, 17, and 20 meters, underscoring the Buddipole's effectiveness in real-world scenarios. Tuning the Buddipole proves straightforward on bands down to 20 meters, though the review notes significant challenges with SWR on lower bands like 40 meters, where achieving better than 3:1 SWR was problematic. Observations also include SWR variations with dipole rotation and mast height, suggesting environmental factors play a role. The overall manufacturing quality of the antenna and its accessories, including the tripod and carry bag, is deemed good, despite a minor issue with a pole connector. Looking ahead, the author plans to construct a homemade Buddipole version, possibly optimized for the 30-meter band, specifically for PSK31 operations from an apartment. This personal project reflects a common amateur radio practice of adapting commercial designs for specific needs, further extending the utility of portable antenna concepts.

A bazooka coax antenna for 40 meters band design by CA6TYS

Design a parallel circular wire balanced transmission line with this online calculator. This calculator is a tool for designing balanced transmission lines with a specific desired characteristic impedance Zc and made of parallel circular conductors of a given diameter d.

The TransWorld Antennas TW4040 The Adventurer Monobander™ is a portable HF antenna designed for rapid deployment in field operations, including **SOTA** and **POTA** activations. This manual details the antenna's assembly, tuning procedures, and operational guidelines for optimal performance on the 40-meter band. It outlines the specific components, such as the telescoping whip and base unit, required for proper setup. Instructions cover mast erection, radial wire deployment, and impedance matching to achieve a low **VSWR** across the designated frequency segment. The document also provides guidance on antenna orientation and environmental considerations for portable use. It specifies the antenna's power handling capabilities and physical dimensions when fully deployed and collapsed for transport.

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.

This site is dedicated to design and analysis of micro- and millimeter wave filters from 0.5 to above 100 GHz.

This is perhaps the most important parameter in many oscillators and it deserves an in-depth discussion on what it is, how it affects a system and how it can be minimised in an oscillator design.

A homemade band pass filter for the 30 meter band based on the original VE7BPO design

The 160-meter amateur radio band, spanning 1.8 to 2 MHz, was historically the lowest frequency amateur allocation until the introduction of the 630-meter and 2200-meter bands. ITU Region 1 allocates 1.81–2 MHz, while other regions use 1.8–2 MHz. This band, often called "Top Band" or "Gentleman's Band," was established by the International Radiotelegraph Conference in Washington, D.C., on October 4, 1927, with an initial allocation of 1.715–2 MHz. Effective operation on 160 meters presents significant challenges due to the large antenna sizes required; a quarter-wavelength monopole is over 130 feet, and horizontal dipoles need similar heights. Propagation is typically local during the day, but long-distance contacts are common at night, especially around sunrise and sunset, and during solar minimums. The band experienced a resurgence after the LORAN-A system was phased out in North America in December 1980, leading to the removal of power restrictions.

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.

The Superantennas MP-1 portable HF antenna is analyzed for its design and field performance, particularly its high-Q loading coil and 3/8-inch mounting. The review details the antenna's construction, including an 8-inch vertical section, a large-diameter loading coil tuned by a sleeve, and a 4-foot whip that disassembles into six rods for transport. Initial testing with the supplied 10-foot ribbon cable "ground plane" yielded poor SWR and RF hot conditions, indicating an inadequate ground system. Further experimentation with longer radials and resonant counterpoises for each band improved matching and eliminated RF hot issues, but introduced significant operational complexity. The author notes the difficulty in optimizing both counterpoise length and coil setting without an antenna analyzer, and the sensitivity of the MP-1 to counterpoise deployment. The review also discusses the recommendation to tune for maximum received signals rather than minimum SWR, often necessitating an external ATU due to the antenna's typical low impedance. The **MP-1**'s critical dependence on resonant counterpoises for effective operation, especially when elevated, is highlighted as a major drawback for portable use. The author ultimately sold the antenna, concluding that despite its sound technical design, its fussy nature and the need for extensive counterpoise management or an ATU detract from its portability and convenience compared to simpler, less expensive dipole solutions. The **Superantennas MP-1** is deemed a flawed portable antenna, requiring considerable effort to achieve its claimed performance.

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.

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

The article, "Using 75 Ohm CATV Coaxial Cable," details methods for employing readily available 75-ohm CATV hardline in standard 50-ohm amateur radio setups. It addresses the inherent impedance mismatch and practical considerations, such as connector compatibility, for hams seeking cost-effective, low-loss feedline solutions. The resource specifically contrasts common 50-ohm cables like RG-8, RG213, and _LMR-400_ with 75-ohm hardline, highlighting the latter's lower loss characteristics, particularly at VHF and UHF frequencies. It explores two primary approaches to manage the impedance difference: direct connection with an acceptable SWR compromise and precise impedance transformation. The direct connection method acknowledges that a perfect 1:1 SWR is not always critical, especially when using low-loss coax. For impedance transformation, the article explains the use of half-wavelength sections of coax to reflect the antenna's 50-ohm impedance back to the transmitter, noting its single-frequency effectiveness. It also briefly mentions transformer designs using toroid cores and a technique involving two 1/12 wavelength sections of feedline for broader bandwidth. The content further clarifies the concept of _velocity factor_ for calculating electrical versus physical cable lengths, providing a generic formula for precise length determination. It notes that while half-wave matching is practical for 10 meters and above, it can result in excessively long runs for lower bands like 160 meters, potentially adding **250 feet** of cable. The article also mentions achieving a usable bandwidth of 28.000 MHz up to at least **28.8 MHz** on 10 meters with specific transformation techniques.

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.

Demonstrates the product line of CAIG Laboratories, focusing on specialized contact cleaners and lubricants essential for maintaining electronic components. Key products include **DeoxIT**, designed for deoxidizing and protecting electrical connections, and **DeoxIT Gold (ProGold)**, formulated to enhance conductivity and provide long-lasting protection on plated surfaces. Details the application of these solutions across various electronic devices, from audio equipment to critical ham radio gear, ensuring optimal signal integrity and component longevity. The product range also features **DeoxIT Faderlube (CaiLube MCL)**, specifically engineered for conductive plastic and carbon-based controls, mitigating wear and improving tactile feel. Explains how proper contact maintenance with these products can prevent intermittent connections, reduce noise, and extend the operational life of switches, potentiometers, and connectors in both commercial and amateur radio applications.

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 102-inch vertical whip, commonly a CB antenna, forms the core of this low-profile 10-meter antenna design, optimized for the 28 MHz band. The construction details specify three 8-foot radials made from scrap wire, connected to a common point. This simple yet effective setup is designed for ease of construction and deployment, making it accessible for operators with limited space or materials. The design emphasizes using readily available components, including PVC pipe for the mast and a SO-239 connector for the feedline, ensuring a straightforward build process for a resonant quarter-wave vertical. Field results indicate that this antenna provides good performance for local and DX contacts on 10 meters, despite its compact footprint. The author, N8WRL, shares practical insights into its construction and tuning, highlighting its suitability for temporary or permanent installations where a full-sized antenna might be impractical. Comparisons to more complex designs suggest that this low-profile vertical offers a respectable signal-to-noise ratio and effective radiated power for its size, proving that simple designs can yield satisfying on-air results.

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.

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

The electchester vhf club is located in flushing, queens, ny and operates an arrl coordinated, 2 meter, vhf repeater designed for amateur (ham) radio use.

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

Documents the construction of a **VHF/UHF** antenna addition for the Buddipole HF antenna system, leveraging the existing Versa-Tee component. The project details the fabrication of a custom antenna mount from angle aluminum, including specific drilling and tapping for 3/16"-24 bolts, and the creation of radials from Simpson Strong Tie Insulation Supports. It specifies radial lengths for 70 centimeters (6 inches from the center stud) and 2 meters (19 1/4 inches), noting the use of wire nuts for safety. The resource outlines the construction of a mast from 1/2" ID PVC conduit, connected with 3/8"-24 connecting nuts and bolts, mirroring the Buddipole's modular design. It describes the integration of a mobile dual-band antenna with a 3/8"-24 mounting stud and the custom coax setup with BNC and **PL-259** connectors. Field testing with an FT-817ND and a separate dual-band SWR meter confirmed good SWR on both 2 meters and the 440-450 MHz section of 70 centimeters, with positive reception reports during Field Day activities. Further, the article describes the creation of a custom carrying solution, including a 22-inch tripod bag and a fabric roll-up, to emulate the portability of the original Buddipole system.

The Lakeshore Repeater Association (KR9RK) operates a **VHF** 2-meter repeater on 147.270 MHz, utilizing a +600 kHz offset and a 100 Hz PL tone, serving the Raymond, Wisconsin area. The organization provides access to monthly newsletters, with recent editions including March 2026, February 2026, and January 2026, detailing club activities and operational updates. A Google Docs link is provided for newsletters with functional embedded links, addressing issues with PDF versions. The association's Megacycle Group is actively constructing a **DX Contest** level HF network, designed for remote accessibility. This initiative aims to provide members with a competitive edge in global DX hunts by enabling worldwide access to the station's radios. Additionally, the Lakeshore Radio Association is commemorating its 50th anniversary with a special event station, K5O, inviting all members to participate in on-air operations.

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

The antenna in this project is a modification of the techniques used to design a multiband fan type dipole with little or no tuning involved having a total space of 105 feet

Demonstrates the complete design and development process for a **Low Noise Microwave Amplifier** (LNA), beginning with conceptual design and progressing through prototyping. The tutorial series covers the initial stages of a single-ended first gain stage, focusing on critical parameters such as noise figure, gain, and stability. It systematically details the theoretical underpinnings and practical considerations for achieving optimal performance in microwave frequency applications. This resource provides a structured approach to LNA construction, enabling radio amateurs and RF engineers to understand the iterative steps involved in realizing high-performance receive-side amplification. It offers insights into component selection, impedance matching networks, and the measurement techniques required to validate design specifications, particularly for **microwave** band operation where noise performance is paramount.

Redesigning CDE rotator control meter scale for north-centered operation

Constructing a dip oscillator provides radio amateurs with a fundamental piece of test equipment for resonant circuit analysis. This particular design, adapted by VK3YE from a concept by _Drew Diamond VK3XU_, details a practical build using readily available components. The unit incorporates four plug-in coils, covering a frequency range from **2.6 MHz to 55 MHz**, mounted on 5-pin DIN plugs for versatility. A salvaged two-gang air dielectric variable capacitor, fitted with a vernier reduction drive, serves as the tuning mechanism, with the smaller gang optimizing bandspread at higher frequencies. In practical application, the dip oscillator is used by setting the meter needle to approximately two-thirds scale. When the instrument's coil is brought near a tuned circuit under test, a noticeable dip in the meter reading indicates resonance. This allows for precise measurement of resonant frequencies in antennas, filters, and other RF circuitry, proving invaluable for homebrewing and troubleshooting. The design emphasizes short wire runs for stable operation, particularly at the higher end of its operational range.

Complete collection of the four main parts of this excellet research on modelling and designing half wave dipole antennas for 40 meters band, covering all aspects beginning from full wave length antennas, to shortened, loaded and reshaped dipoles

A great and efficient monoband VHF portable antenna. The article consist of two version of a 12.5 Ohm 3 elements yagi beam antenna plans for the two meter band, a full sized and a shortened version expecially designed for the SSB and CW on 144 MHz.

A light and sturdy Quad for 10 and 15 meters. Basic Quad antenna design considerations. Building and assembling a dual band HF QUAD antenna, designing and joining cross-arms and boom, assembling spreader and element wire installation notes. QST article.

Antenna manufacturing & design, antennas for limited spaces, Home of the rugged 160 Meter sloper antenna

The antenna almost repeat the design of the Car Antenna however instead of aluminum tubes it was used copper wire in plastic insulation in diameter of 2- mm (12 AWG).

The Maria Maluca HF multiband antenna as designed in 1957 by PY2BBP is a directive antenna for 15 meter and a passive element that works as director and reflector in different bands

An experimental prototype of an asymmetrical hatted vertical dipole antenna that can work on HF bands 20 to 10 meters band. The AHVD Vertical dipole is an upside-down T design

Demonstrates the construction of a high-power 6-meter (50 MHz) amplifier, specifically designed for demanding modes like EME, TEP, and multiskip Es. It details the use of a _GU-43B_ tetrode in a grounded-cathode configuration, emphasizing the need for stabilized grid voltage and input capacitance compensation. The resource provides a comprehensive schematic, power supply design, and practical considerations for component sourcing, particularly for high-voltage and high-current sections. The builder achieved an output power of **1250 watts** with an anode current of 0.65 amperes and 3200 volts anode voltage. The article also covers the physical construction within a modified P6-31 enclosure, outlining the internal layout for RF and power supply sections, and includes photos of the completed unit. It highlights critical safety precautions for working with high voltages and reactive currents up to **20 Amperes** in the P-network.

Constructing a basic multimeter involves integrating a 0-1mA meter movement with various shunts and multipliers, selected via a switch, to create a versatile instrument capable of measuring DC volts, current, and resistance. The design outlines two main units: a primary unit handling six DC current ranges up to 1 amp and eight DC voltage ranges up to 1000 volts, alongside an internal battery for an ohms range up to 200,000 ohms. This approach allows for a practical, hands-on understanding of meter operation. An add-on unit further extends the multimeter's capabilities, incorporating a meter rectifier and switched series resistors to provide four AC voltage ranges up to 100 volts. Additional shunt and series resistors, designated Ra and Rb, are included to expand the instrument's range to 10A and 5kV, demonstrating how modular design can enhance functionality. When this add-on is in use, the main instrument is set to measure 1mA FSD, connecting via specific lugs. Component selection emphasizes precision, with 1% tolerance high stability resistors for series elements and Eureka resistance wire for shunts. The design specifies values calculated for a meter with 60 ohms internal resistance, noting that these would require modification for different meter characteristics. Experimental adjustment of shunt values is recommended to ensure accurate readings against a calibrated reference meter, reinforcing practical calibration techniques.

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

Online variometer calculator by IN3OTD

A 0-30 MHz step attenuator, constructed from switchable Pi attenuation pads, provides a practical tool for evaluating receiver sensitivity and calibrating S-meters. The design utilizes readily available 5% tolerance resistors, with values derived from paralleled components to achieve specific attenuation steps. A schematic (Fig 1) illustrates the circuit, including PCB pad shielding, while a table details required and actual resistor values, along with percentage differences. Measurements of voltage input versus output at various frequencies are used to calculate dB attenuation, presented in a graph (Fig 4). The resource includes formulas for determining output voltage from a known input and a comprehensive 0-40 dB voltage multiplier table, which is crucial for precise signal level management. The project also references external attenuator calculators and equations for further study. Photos (1-3) provide visual guidance for the assembled unit, showing bottom, top, and front views. The project emphasizes the use of **Pi attenuation pads** and **receiver sensitivity** evaluation, offering a hands-on approach to RF signal management.

One of the featured products, the V350 CAMP, is a multiband vertical antenna covering 6 to 80 meters, priced at R$ 799,90, demonstrating the range of ready-to-use solutions available. The inventory includes various antenna types such as **HF**, **VHF**, and **UHF** designs, along with dual-band options like the J-Pole Dual V/UHF for R$ 235,00. For those building their own arrays, the store stocks essential components like element holders, clamps, junction boxes, and aluminum plates, alongside specialized items such as the KIT Isolador Central Dipolo - 01DX for R$ 99,90. The shop also provides a comprehensive selection of installation hardware, including diverse antenna mounts, PTT supports, and various coaxial cables like RG58 and RG213, with prices up to R$ 849,90 for RG213. Connectors such as UHF male PL259 and various adapters are readily available, ensuring compatibility for different setups. Additionally, specialized items like side handles for popular transceivers such as the FT857/891 and IC7300 are offered, catering to specific equipment needs. Beyond antennas, the store supplies practical accessories like transport bags, 12V power cables for transceivers, and even branded merchandise like the Antena Kit mug. Rodrigo Gonçalves, PP5BT, manages the operation from Blumenau, SC, Brazil, providing direct contact via WhatsApp at +55 47 9.9985.0155.

Elements are aluminum TIG soldering rods 4.0mm of diameter, almost 1m long, these objects are light, thin and flexible based on the RZ9CJ Design

an overview, introduction or tutorial about the basics of electronics filters including the types of filter and the various filter design considerations and parameters

The page provides information on a simple 50MHz J-Pole Antenna project based on the DK7ZB design. It explains the principle of the Wireman-J-Pole, the feeding process, practical mounting, and simulation results using MMANA GAL. The content aims to guide amateur radio operators in building their own J-Pole antennas for the 6-meter band.

Over 150 pages of content are dedicated to maximizing activity on the 6-meter band, often referred to as the _Magic Band_. The resource details various propagation modes, including sporadic E, F2, and tropospheric ducting, providing insights into their characteristics and how to leverage them for DX contacts. It also covers essential equipment considerations, from transceivers and transverters to specific antenna designs optimized for 50 MHz operation, such as Yagis and Moxon antennas. The eBook presents strategies for participating in 6-meter contests and pursuing awards like _VUCC_, offering practical advice on logging software and operating techniques. It includes discussions on software tools useful for predicting propagation and managing contacts, alongside guidance on finding and utilizing DX maps to identify openings. The author, K5ND, shares his extensive experience to help operators achieve successful 6-meter DXing. Specific sections address the code of practice for 50 MHz operations and provide assistance in locating rare DX opportunities. The content is structured to guide both new and experienced operators through the nuances of the band, from initial setup to advanced operating strategies.