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A shortened 160 meters band antenna for hams who do not have 260 ft of space, based on a open-wire-fed short dipoole

A 70cm and 2m 6 elements yagi antenna plan based on the IEEE Transactions on Antennas and Propagation

Demonstrates the construction of a _3MA triband mobile antenna_ designed by IZ7DJR, emphasizing a full-size quarter-wave whip for 10 meters. The design incorporates a rapid tilt-down mechanism to facilitate quick changes of loading coils for operation on 15 and 20 meters. This approach aims to minimize losses and enhance efficiency compared to conventional base-loaded mobile antennas. The resource provides specific coil winding data: 22 turns for 15 meters and **37 turns** for 20 meters, both using 1mm wire over an 80mm coil length. The 10-meter band operates without a loading coil, leveraging its full-size design. The author's design prioritizes ease of band switching and improved performance for mobile HF operations, offering a practical alternative to more lossy commercial options.

Icom Kenwood Yaesu MyDel dealer, offer a wide range of ham radio products, transceivers, antennas, rotators, microphonrs, aerials, dummy loads, rf amplifiers and scanners based in UK

US Antenna manufacturer offering base and mobile antennas for 2 meter, 1.25 meter and 70 cm Amateur Radio GMRS and MURS Citizens Band Radio VHF and UHF Business Band Radio HF, VHF and UHF Scanning

A very efficient 80 meter Counterpoise antenna designed to reduce ground losses from inadequate radial systems beneath inverted L antennas, a project by DM2GM and DM4IM based on the original K2AV antenna concept.

Communication scanners, antennas and cables canadian dealer based in Norwich Ontario

Amateur Radio HF Cubical Quad and Delta Loop antennas manufacturer based in Spain

An interesting article on loading short vertical monopole antennas, representing six different methods. Base loading, Center Loading, Top Loading, Continuous loading, half and half loading and capacitive top loading.

The X80 multi-band HF vertical antenna, a commercial iteration of the Rybakov design, exhibits a physical length of 5.5 meters, or approximately 18 feet, and is constructed from aluminum tubing. It operates as a non-resonant vertical, requiring an external antenna tuner for impedance matching across its intended operating frequencies. The antenna's design incorporates a 1:4 UNUN at its base, facilitating a nominal 50-ohm feed point impedance for the coaxial cable. Performance observations indicate effective operation on 40 meters, 20 meters, 15 meters, and 10 meters, with reduced efficiency on 80 meters and 160 meters due to its relatively short electrical length for these lower bands. Comparative analysis with a G5RV dipole and a half-wave end-fed antenna reveals the X80 offers a lower take-off angle, beneficial for DX contacts, particularly on the higher HF bands. Field tests conducted with an Icom IC-706MKIIG transceiver and an LDG AT-100ProII autotuner demonstrate the X80's ability to achieve acceptable SWR across 80m through 10m. The antenna's compact footprint and ease of deployment make it suitable for restricted spaces or portable operations, though its performance on 80 meters is noted as a compromise compared to full-size resonant antennas.

Fabricates baseplate components, and provides hardware kits for DIY hex beam, spiderbeam and moxon antennas.

LnR Precision Inc. is a North Carolina based company that specializes in Par EndFedz amateur radio antennas and MantiZ QRP Transceivers. Their most popular products include End-Fed QRP portable antennas and HF FX Series QRP Transceivers.

This web article by VK3BLG details the construction of an experimental 70cm (432 MHz) circularly polarized patch antenna, intended for satellite communication. The resource provides dimensions, feed point specifications, and impedance matching considerations for a single patch element, with discussion extending to array configurations for circular polarization. Construction involves a copper patch element on a dielectric substrate, fed via a coaxial cable. The design is based on information derived from AO-40 satellite antenna specifications, focusing on achieving circular polarization for satellite reception. The article includes specific dimensions for the patch and feed points, along with impedance values. Validation is implied through on-air satellite reception reports, with initial signal reports of **1 S-point above noise** for AO-40 beacons using a grid reflector, improving to **3-4 S-points above noise** with a 2-turn helical feed. The author references a _NanoVNA_ for impedance measurements and discusses the relationship between slot and dipole antennas in the context of patch design. DXZone Focus: Web Article | 70cm Patch Antenna | On-Air Satellite Reception | Circular Polarization

European supplier of radio communication receivers and scanners, transceivers, antennas, cables, connectors, GPS and accessories based in Prhaha Czeck republic.

A system designed to automatically tune small transmitting magnetic loop antennas, particularly beneficial for **contest operations** where rapid frequency changes are common. The core of the system involves a PC-based control application, AutoCap, written in C#, which monitors antenna SWR via an external meter and commands a motor interface to adjust the loop's variable capacitor. The software is compatible with Windows and Linux via the Mono framework, offering a graphical user interface for monitoring system status, SWR, power, and motor commands. Key components include one or more magnetic loop antennas equipped with DC or stepper motors for capacitor adjustment, an SWR meter with data output (such as the Telepost LP-100A or a homebrew serial/USB SWR meter), the AutoCap PC software, and a motor interface. The most effective motor interface utilizes an **Arduino-based controller** with custom firmware, providing precise control over both simple DC motors and stepper motors, and supporting features like motor braking for finer adjustments. The system allows for configurable SWR thresholds, pulse widths, and motor effort settings to optimize tuning speed and resolution. Optional radio integration provides frequency hints, enabling the algorithm to learn the relationship between motor actions and resonant frequency, thereby speeding up initial tuning responses. The software also supports antenna profiles, allowing operators to save and recall specific configurations for different loops, including accumulated frequency hint data.

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.

DK7ZB's fan dipole designs address the challenge of operating multiple HF bands with a single feedline, providing practical construction details for **multiband wire antennas**. The resource outlines specific lengths for half-dipoles across various band combinations, including 10-15-20m for classic bands and 12-17-30m for WARC bands. It emphasizes the importance of proper spacing between resonant elements to avoid impedance interaction and high SWR, a common issue when frequencies are too close. The article details the use of **current baluns** built with FT240-43 or FT140-43 cores, specifying turns and cable types for 1KW and 400-Watt power levels. It includes a correction table for adjusting dipole lengths based on frequency shifts, aiding in fine-tuning resonance. The 20+40m dipole is noted for its ability to operate on 15m with an ATU, demonstrating versatility.

Spipral antenna principle by a concept of Bill Petlowany, K6NO. Tak Antennas are based on this principle, using spirals as dipole linear wires.

Based on a simple project based on a 2 elements Yagi for 20m band, and then becomed a triband yagi with a open-sleeve feed system

Specialize in engineering, design and repair of all rf equipment. Dealer for two way radios, scanners, shortwave radios, wi-fi antennas, wifi amplifiers. Based in Fortuna, California.

Supplier of two-way radio products and accessories to large and small businesses, volunteer groups, radio amateurs and individuals. Transceivers, receivers, antennas cw keys based in London UK

Amateur radio accesories, power supplies, electronic parts, antenna controllers and antennas manufacturer based in Spain

A low-cost SWR meter project based on Arduino that works with AutoCap automatic antenna tuner for magnetic loop antennas

Valcom Guelph specializes in the design and manufacturing of a full range of MF Beacon 100 KHz - 600 KHz, AM Broadcasting 540 - 1700 KHz, HF 1.8 - 30 MHz, VHF 30 - 300 MHz and UHF 300 - 1,200 MHz and SHF up to 6 GHz antennas based in Canada

Accessories, Antennas and Battery chargers. Radiators, Repeaters, Yagi, Mag, Car, Tetra, Marine, Multiband, Brackets, Mounting accessories, cables and connectors, radiokits, special cables etc. Based in Finland

Super Antenna Systems for HF - VHF - UHF Portable Stealth Mobile Base Backpack EmComm Ham Radio antennas

Amateur radio antennas manufacturer, produce multiband and monoband high performance yagi antennas and vertical antennas based in Poland

Ham Radio Vertical HF multiband antennas manufacturers based in Spain

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.

Antenna manufacturer based in Brazil, produce mobile HF VHF and UHF antennas and VHF UHF Base antennas

A 2 elements delta loop antenna for 14 MHz with a MMana simulation file, dimensions, pictures of this aluminium tube based delta loop antenna, and matching system details.

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.

Ultra portable and lightweight folding beam antennas based on G3TXQ design

The OZ1CX center-loaded mobile antenna project details the construction of a compact **80-meter** antenna, specifically designed for mobile, portable, and stationary operations. It features a loading coil wound on a 50 mm PVC pipe with 1.5 mm copper wire, comprising 100 turns over 150 mm length, resulting in an inductance of 150 µH. The design incorporates a 1.5-meter whip and a 1.5-meter base section, with the coil positioned at the center for optimal performance on the 3.5 MHz band. Performance measurements indicate a **VSWR** of 1:1.2 at 3.7 MHz when mounted on a vehicle, achieving a bandwidth of 30 kHz for VSWR below 1:2. The antenna's efficiency is compared to a full-size dipole, showing a signal strength reduction of 3-4 S-units, which is typical for compact mobile HF antennas. Practical application notes cover tuning adjustments by varying the whip length and coil tap points, emphasizing the importance of a good ground plane for effective operation.

SJ2W Contest Station, antenna for the 160 meter is a 39m vertical. This 160m antenna consist of 29m of WIBE tower sections with an insulated base and 10m top tube.

Manufacturers of professional Civil & Defense UHF/VHF Base Sation Antennas,Installation Hardware, Power Splitters and Distributors of EUPEN rf Cable & Connector products.

Antennas manufacturer based in Germany produce portable and wire HF VHF antennas

Amateur radio Quad Antennas manufacturer based in Italy produce HF and VHF Quad antennas, and spare parts.

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.

Aerial 51 is an antenna manufacturer producing HF Wire antennas. Their antenna product catalog includes portable, OCF wire antennas for HF bands but also QRP transceivers, and accessories for portable operations.Based in Germany

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.

Ham radio shop based in Holland, dealer for cb radio products, amateur radio transceiver,Yaesu Icom and Kenwood, antennas cables and accessories

Amateur radio antennas manufacturer based in Italy. Produces HF end-fed, dipoles, and other wire antenna types, mono band and multi band antennas.

The Homebase-10 is a wire halo antenna for 10m built with DIY store parts, effective despite its small size. Includes a dual-band version for 10m and 6m with gain around 0 to -2dBd, near omnidirectional pattern, and horizontal polarization. Overview based on a 2008 Practical Wireless article.

Comprod Communications specializes in the design and manufacturing of RF communication solutions, including a comprehensive range of antennas, duplexers, multicouplers, and combiners. The resource details their product categories, which encompass base station antennas, mobile antennas, transit antennas, and disguised antennas, alongside mounting solutions and in-building systems. It highlights the company's 40-year history in adapting offerings to client needs and anticipating industry trends, emphasizing product durability and low maintenance for harsh environments. The company's offerings are presented as high-quality, designed to withstand extreme conditions from Arctic cold to equatorial heat and humidity. The site mentions solutions and technical sales support, training, and site analysis and system design as part of their service portfolio. It also references being a market leader trusted by over 1,000 customers worldwide, positioning itself as a partner for RF communication needs.

British ham radio antenna products manufacturer, base and portable antennas, mobile antennas, baluns, masts, production is mostly based on wire and whip antennas

Article based on ROHN engineering specification that will guide on proper guying heights and guy lengths when guying ham radio antenna masts. It will help you determine ahead of time the proper length of guy wires and the distance from the base of the mast to the anchor points

Daki Funkversand is a German based web shop for Amateur- & CB-Radio equipment. Our shop includes products such as radios, antennas, equipment, PMR, LPD & Freenet.

Sixty-meter repeaters typically use a 1 MHz frequency separation between input and output, while 2-meter repeaters commonly employ a **600 kHz** split and 70-centimeter repeaters use a **5 MHz** offset. This article details the fundamental technical principles of amateur voice repeaters, explaining how they extend VHF/UHF communication range by receiving on one frequency and simultaneously retransmitting on another. It covers essential components such as receivers, transmitters, filters, and antennas, often situated on elevated locations for optimal coverage. The resource delves into the critical challenge of _desensing_—where the repeater's strong transmit signal overpowers its own receiver—and the engineering solutions employed, including antenna separation and the use of high-Q cavity filters. It also explores various control and timing systems, from basic squelch activation to more sophisticated microcontroller-based boards that manage functions like voice identification, time-out timers, and fault protection. Different access methods are discussed, including open access, toneburst, CTCSS subtone, and DTMF, each offering distinct advantages for managing repeater usage and mitigating interference. Furthermore, the article examines repeater linking, both conventional RF methods and modern internet-based solutions, highlighting how linking expands coverage and promotes activity across multiple repeaters or bands. It introduces less common repeater types such as 'parrot' repeaters, which use a single frequency and digital voice recording, and linear translators, capable of relaying multiple signals and modes simultaneously across different bands, often found in amateur satellites.

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.