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The mark 2 Crossfield Antenna was described in Sprat 76 by Alec, GD3HQR

Amateur, scanner, wi-fi and land mobile antennas and accessories online store

Ham radio Blog, focusing on homebrewing and testing antennas, rig mods and contesting.

The current, the voltage, the impedance, the bandwidth, the polarization, and how the earth influences the famous radiation pattern.

The HarRe antenna series, multi element quarter wave resonant broadcaters band receiving antenna

Microcontrollers for many ham radio applications including repeater controllers, beacon transmitters, keyers, antenna switches, battery monitors, etc.

A review of the Buddipole Deluxe Antenna portable HF VHF ham radio antenna

Amateur radio installation services and products for sale. Tower erection services, shack setup, antenna installation

Operating the _Icom IC-746_ HF/VHF transceiver often presents specific technical questions, and this resource compiles a comprehensive Frequently Asked Questions (FAQ) document in an ASCII text format. It details common inquiries and solutions related to the rig's functionality, accessories, and potential modifications. The content is structured into distinct sections addressing general information, power supplies, antennas, microphones, keyers, amplifiers, TNC integration, and optional IF filters. The FAQ provides practical guidance on topics such as configuring the internal automatic antenna tuning unit (ATU), selecting appropriate power supplies, and understanding microphone pin-outs. It also delves into advanced subjects like computer control via CI-V, wiring for PSK31 operation, and troubleshooting common issues like low S-meter readings on 2m FM or loose tuning shafts. Specific questions cover the installation of optional IF filters, comparing Inrad versus Icom filters, and optimizing filter combinations for various modes. Furthermore, the document outlines various hardware and firmware modifications, including those for increasing monitor volume, replacing LCD driver transistors, and implementing a "poor man's TCXO." It even touches upon untested modifications, such as replacing PIN diodes in the demodulator. The FAQ also lists manual errata and discrepancies, offering a robust knowledge base for IC-746 owners seeking to optimize their station or resolve operational challenges.

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.

Home-Made Magnetic Loop Antenna for 30 Meters by WA8LMF

Spanish HexBeam antenna manufacturer, produce antennas kits, and part for HexBeam antennas

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.

Vhf and UHF homebrewers of hardware and antennas. Find help, idea, or someone with just the same interest as you.

MW0JZE Manufacturer of the G3TXQ Broadband Hexagonal Beam - HexBeam Antennas

Cushcraft XM240 transformation into a Moxon antenna by W6NL

Stryker 10 Meter Amateur Radio trasceivers, antennas and accessories manufacturer

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

Ham radio HF antennas manufacturer, produce HF dynamic beam antennas, and vertical pole antenna. Offer kits and parts to build you own dynamic antennas, by IZ0AEG

Refurbishing my 10 years old Cushcraft A3S triband HF Antenna

Ham radio shop in South Salem, NY, dealer for Alinco, LDG, Cable X-perts, Jetstream and several antenna types and makers

The _Sci.Electronics FAQ: Repair: RFI/EMI Info_ document, authored by Daniel 9V1ZV, provides a detailed analysis of computer-generated RFI/EMI, focusing on its impact on radio reception. It identifies common RFI sources such as CPU clock rates (e.g., 4.77 MHz to 80 MHz), video card oscillators (e.g., 14.316 MHz), and even keyboard microprocessors, all of which generate square-wave harmonics across HF and L-VHF regions. The resource outlines a systematic procedure for pinpointing RFI origins, including disconnecting peripherals and using a portable AM/SW receiver with a ferrite rod antenna to localize strong interference sources. The document categorizes RFI mitigation into shielding, filtering, and design problems, offering practical solutions for each. It recommends applying conductive sprays like _EMI-LAC_ or _EMV-LACK_ to plastic casings of radios, monitors, and CPUs to create effective Faraday cages, emphasizing proper grounding and avoiding short circuits. For filtering, the guide suggests using line filters, ferrite beads, and toroids on power and data lines, and small value capacitors (e.g., 0.01 uF for serial/parallel, 100 pF for video) to shunt RFI to ground. It also discusses the use of bandpass, high-pass, low-pass, and notch filters on the receiver front-end or antenna feed to combat specific in-band noise.

HF Beam Calculator for Amateur Radio and CB Communications

KD5FX, 20 through 6 meters, QRP to full legal power, lightweight, easy to carry

AD7DB discussion about HF wire antennas

Operating a ham station often involves encountering radio frequency interference (RFI), RF feedback, or RF burns, which are frequently misattributed to poor equipment grounding. This resource meticulously dissects these assumptions, asserting that RF grounds on the operating desk often merely mask more significant system flaws. It identifies five primary causes for RF problems, including antenna system design flaws, proximity of the antenna to the operating position, DC power supply ground loops, equipment design defects, and poorly installed connectors or defective cables. The content emphasizes that issues like "hot cabinets" or changes in SWR when connecting a ground indicate substantial RF flowing over wiring or cabinets, a phenomenon known as common-mode current. The article provides detailed explanations of common-mode current generation, particularly from single-wire fed antennas like longwires, random wires, and OCF dipoles, which inherently present high levels of RF in the shack. It also illustrates how vertical antennas, lacking a perfect ground system, can excite feed lines with significant common-mode current. Through simulations, the author demonstrates how a dipole without a proper _balun_ can cause RF problems at the operating desk, showing current patterns and voltage distributions on feed line shields. The discussion extends to the proper application of _RF isolators_ and _ferrite beads_, clarifying their role in modifying common-mode impedance on cable shields and cautioning against their use as a band-aid for fundamental system defects. The resource advocates for correcting the actual source of RF problems, such as antenna system issues or poor connector mounting, rather than relying on internal shack grounding or isolators. It highlights that properly functioning two-conductor feed lines, like coaxial or open-wire lines, should result in minimal RF levels at the operating position, even without a desk RF ground. The author shares personal experience, noting that his stations since the late 1970s have operated without RF grounds at the desks, relying instead on proper antenna system design and feed line integrity.

KB9AMG's Top WSPR Spots presents a focused online tool for monitoring **2-way WSPR reports**, specifically detailing propagation data from February 2026 through March 2026. This resource aggregates _WSPRnet_ data, allowing radio amateurs to observe weak signal propagation conditions across various bands. The interface is straightforward, presenting callsigns, frequencies, signal-to-noise ratios, and distances for each reported contact, which is crucial for understanding current band openings and signal paths. The utility of this WSPR spotter lies in its ability to quickly visualize global propagation. Users can identify active stations and assess signal viability over long distances, with reports often showing contacts spanning thousands of kilometers. For instance, a typical WSPR report might indicate a signal from Europe reaching North America with a _SNR_ of -25 dB, demonstrating effective low-power communication. This data is invaluable for planning DX operations or evaluating antenna performance under actual propagation conditions.

The page provides detailed instructions on how to build a 60 meter End Fed Half Wave Antenna Tuner, with large pictures and diagrams. It is aimed at amateur radio operators looking to construct their own antennas for the 60 meter band.

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

M0CVO Antennas, amateur radio antennas for fixed station or portable operations, HF/6m all are catered for. The antennas produced by us are all manufactured by Nigel Booth, M0CVO

The Superphaser-2 is an antenna phasing unit based on the PSA-A Phase Shift Amplifier module

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.

Filters for the commercial 2 way market, MATV, FM broadcast, laboratory, marine industry, amateur radio, scanner and short wave. Antenna for amateur radio bands

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.

US amateur radio antenna manufacturer. Produce baluns, delta loops, dipoles, ocf antennas and more

Ham radio dealer. Antennas, connectors, books, maps baluns and spare antenna components

Investigates the legal framework surrounding **pneumatic antenna launchers** in Victoria, Australia, specifically their classification under the Firearms Act 1996. The author, VK3KBC, details how these devices, designed to discharge a projectile by compressed air, are defined as 'firearms' and subsequently categorized as **Category E Longarms**. This classification carries significant penalties for unregistered possession or use, with the author noting the lack of provisions for amateur radio operators to legally possess and use such devices for antenna deployment. The author shares personal experiences needing such devices for portable HF radio operations, contrasting them with previously legal slingshots and current alternatives like kites or bow and arrow. VK3KBC outlines efforts to advocate for legislative change, including submissions to the Wireless Institute of Australia (WIA) and the Victorian Department of Justice, proposing an amendment to Section 3(i) of the Firearms Act 1996 to include amateur radio field operations as an exempted use. The resource also reviews the original intent of the Category E firearm classification, suggesting that pneumatic antenna launchers may have been assigned this category in the absence of a more suitable alternative.

The author explores the VP2E antenna, introduced by Ed Durrant DD5LP, for Portable Operations on the Air (POTA). Detailing its unique design, successful trials, and an unexpected propagation twist, the VP2E proves a promising addition to the author's portable antenna arsenal.

A Simple Delta Loop Antenna for Smaller Vessels

A copper J Antenna for 144 and 430 article with design, feeding methods and pictures

Ham radio yagi beam antennas manufacturer based in NY USA. Produce monoband and multiband yagi antennas fot HF and VHH

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.

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.

Commsaudit uk, i/q quadrature , hf receivers, rf, multicoupler, multicouplers, switch matrix, antenna matrices, masthead amplifier,, vhf receiver, uhf,

How do two-wire reversible direction Beverages work, an excellent document that explains fundamentals of beverage antennas. This article details the design and performance of a reversible beverage antenna. Leveraging orthogonality between common mode and differential mode currents on a 2-wire line, this antenna facilitates independent reception from both ends. While common mode signals arrive and are summed on a transformer's secondary for common mode reception, differential mode signals induce anti-phase currents, providing individual reception. Various measurements explore impedance, transmission loss, and F/B ratio, highlighting the antenna's effectiveness and areas for improvement. Notably, increasing the antenna's height significantly improved performance.

Over 15 years of operational notes are documented on the AA6E Station Log, covering diverse amateur radio topics. The blog presents detailed accounts of station setup, antenna experiments, and digital mode operations, often featuring specific equipment like the _Ten-Tec Orion_ transceiver. It includes practical discussions on **station grounding techniques** and insights into PSK31 Morse code communication. The resource provides a chronological record of Martin Ewing's amateur radio activities, offering firsthand perspectives on equipment performance and operational challenges. Content often includes technical observations and solutions developed through practical experience, such as optimizing antenna systems for various bands. Specific entries detail contest participation and DX chasing, providing context for operational decisions and results.

The page provides detailed information on a compact two-element yagi antenna, also known as the Moxon rectangle, specifically designed for the 17 meters band. It includes construction details, evolution history, performance data, and comparison with a 1/2 wave dipole antenna.

eHam reviews on Cushcraft MA5B Mini Beam antenna

137 kHz propagation analysis details ground wave and sky wave mechanisms, drawing heavily from **CCIR Rec. 368-6** for ground wave field strength predictions and **CCIR Rep. 265-7** for sky wave modeling. The resource presents field strength values for 1 W ERP at varying distances, considering ground conductivity and permittivity for ground wave, and ionospheric height (70km daytime, 90km nighttime) for sky wave. Key factors like ionospheric focusing (factor "D"), reflection coefficient ("RC"), and antenna ground pattern factors ("Ft", "Fr") are quantified for 137 kHz, enabling calculation of sky wave field strength. Practical coverage ranges are derived for 137 kHz, showing useful ground wave coverage up to 1600 km over seawater and 1100 km over average ground, assuming a -9 dBuV/m noise floor. Sky wave coverage extends beyond 2200 km during night-time and winter daytime, but is negligible during summer daytime at solar minimum. The document also compares ground wave and sky wave strengths, identifying crossover distances at 550 km (night-time), 750 km (winter daytime), and 1250 km (summer daytime), where interference fading can occur. Adjustments for solar maximum conditions are provided, indicating 2-11 dB higher sky wave values depending on distance and season.

Converting a little Radio Shack CB mobile magnet mount antenna to a VHF ham radio antenna