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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.

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

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

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 article deal with various means to covertly operate radio systems while going unobserved.

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

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

How do we make an HF station work more effectively? Antennas are the key!

Sell used low band, mid band and hi band vhf radios and mobile antennas. Used Radio Sales can program these radios to suit your needs.

W3HH wide-band wire antenna Article in French. The W3HH antenna, also known as the Terminated Folded Dipole (T2FD), is a compact, broadband antenna for amateur radio. It operates at an angle of 20 to 40 degrees and covers frequencies from 3 to 30 MHz. The antenna features a total length of one-third of the wavelength at its lowest frequency and is fed using a 1:4 BALUN transformer for impedance matching. A termination resistor around 390 Ω optimizes performance, making it suitable for various amateur radio applications while being easy to construct and install.

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.

In this article you can find solutions to the problem of keeping your ham radio antennas hidden from the CCR Police

Understanding Amateur Radio NVIS Antennas and Propagation

This project details the construction and testing of a M0PLK Delta Loop antenna for the 20-10m ham radio bands. Inspired by positive reviews highlighting its reduced local QRM compared to Cobweb antennas, the author built the antenna using aluminum tubes, DX-Wire FS2 wire, and a 1:4 balun. A mix of custom 3D-printed parts and careful assembly ensured stability and performance. Initial VSWR measurements met expectations, and test QSOs demonstrated success across multiple bands. Future enhancements include adding a lightweight, remote-controlled rotator for directional capabilities.

Homebrewing a vhf bicone antenna with 8 clothes hangers and 4 feet of Sch40 non-metallic rigid conduit

Clark county amateur radio club serving sw washington for 75 years! come find out how our local ham club offers programs that cover everything from the history of morse code and call signs to ham radio antennas

Amateur radio products,wire and yagi antennas, SDR Receivers, upconverters, pre-amplifiers, towers and RTL funcube dongles by CT1FFU

Two different ways to create autotransformer for end fed half wave wire antennas, by using ferrite or air core.

Australian manufacturer of HF Communications Antenna Systems for Military, Comercial, Mining & Amateur Radio

SPX Communication Technologies, operating under the TCI International brand, presents a range of radio frequency (RF) solutions primarily for government, defense, and commercial sectors. The offerings include advanced systems for spectrum monitoring, communications intelligence (COMINT), and high-frequency (HF) and medium-frequency (MF) broadcasting and communication antenna systems. Specific product lines encompass _Blackbird_ COMINT systems, _Scout_ spectrum monitoring receivers, and various antenna arrays designed for robust performance in challenging RF environments. The resource details the capabilities of these systems, such as wideband signal detection, direction finding (DF), and signal analysis, crucial for intelligence gathering and regulatory compliance. It also highlights the engineering behind their antenna designs, which are optimized for specific frequency ranges and operational requirements, including high-power broadcast applications and secure military communications. The information presented emphasizes the integration of hardware and software for comprehensive RF situational awareness. The company's focus on empowering partners to "Command the Spectrum" underscores its commitment to delivering critical tools for signal interception, analysis, and management across diverse operational landscapes.

The problem originates by improper TXOUT-to-RF timing (RF transmission exists still after a TX-EN prohibition), combined by too long decay of their CW pulses.

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

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.

This variation of the basic horizontal, half wavelength flat top dipole has proven to be a simple, effective antenna suitable for both home and portable use.

Main High Frequency Antennas from the 2009 LARC FARL Field Day, Ford Amateur Radio League. A document comparing antenna performances and flexibility among a G5RV an Carolina Windom and a Cushcraft R7 vertical antenna.

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

Online calculator for J-Pole antennas. The J-pole antenna consists of a short and a long vertical pole with a feed point near the bottom. The antenna looks like the letter J, hence the name J-pole antenna.

Le radioamateurisme,le qrp,l elecraft k2, antennas,qrp,schemas,manuals,nostalgia, meteo,dx clusters hf, and contests links in french

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.

Antenna Authority Inc. offers a wide assortment of directional, wideband antennas and other equipment specifically engineered for radio direction finding (DFing) and geolocation applications. Their product line includes _log periodic_, _cavity-backed spirals_, and _Yagi_ antennas, alongside covert antenna solutions for various operational requirements. The company emphasizes its expertise in designing and manufacturing specialized antennas for both overt and covert operations. Beyond standard offerings, Antenna Authority Inc. provides custom design services to meet specific client needs, focusing on tailored RF directional products. Their capabilities extend to developing antennas for vehicles and optimizing their operational performance in diverse scenarios. The firm is located at 3381 W. County Line Road, Douglasville, Ga. 30135-1145. Ferrel Bentley is associated with Antenna Authority Inc., which has been operating since at least 2005, as indicated by the copyright notice.

Blog site for various home brew projects including antennas, power dividers etc

FA-Kleinanzeigen is a dedicated platform for amateur radio enthusiasts in Germany to buy and sell equipment. The site features a wide range of classified ads, including HF and VHF radios, antennas, and accessories. Users can post their listings for free, making it an accessible resource for both seasoned operators and newcomers looking for second-hand gear. The platform categorizes listings into various sections, such as QRP technology, military radios, and even antique equipment, catering to diverse interests within the ham radio community. In addition to equipment sales, FA-Kleinanzeigen also allows users to search for specific items, making it easier to find rare or specialized gear. The site emphasizes user engagement, encouraging individuals to create accounts for posting ads and interacting with other members. With a focus on the German market, it serves as a valuable resource for local hams seeking to expand their stations or offload surplus equipment. Whether you're looking for a new transceiver or just browsing for interesting finds, FA-Kleinanzeigen is a go-to destination for amateur radio classifieds.

ICNIRPcalc allows you to calculate safety distances for many know amateur radio antennas with respect to ICNIRP limits by DL9KCE

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

Ham and Amateur Radio Swap - Buy, Sell, Trade, Swap, radios, amplifiers, antennas and more. Classified ads for Canada, Ontario, Quebec, Maritimes, Prairies, British Columbia and USA

American Radio Supply, LLC is a supplier of quality radio communication parts and wireless connectivity components including coaxial connectors, cables, antennas.

EDC is an amateur radio dealer for Heil Sound, Elecraft, Vibroplex and Force 12 antennas in Japan

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

Basic anctenna theory, general information on antennas

These antennas are larger versions of the small loop antennas that were part of the cardboard back panel of older AC/DC five tube AM radios. Loop antennas of this type were popular in the very early days of radio. They are still useful today for long distance reception of AM radio stations

Cmpter Electronics specializes in the design and manufacturing of RF coaxial connectors, RF adapters, and RF cable assemblies, serving diverse applications across datacom/telecom, automotive, instrumentation, aerospace, and defense sectors. Their product line includes RF coaxial terminations, attenuators, and waveguide to coax adapters, catering to specific needs in radio frequency systems. The company also offers precision adapters and connectors, alongside glass beads and test cable assemblies, indicating a focus on high-quality components for demanding RF environments. Their resource center provides valuable information, including an "RF Made Simple" section and a product catalog for download, which assists engineers and technicians in selecting appropriate components. The product named system helps in identifying specific parts, streamlining the procurement process for complex RF solutions. With a comprehensive range of RF coaxial cables and related tools, Cmpter Electronics positions itself as a key supplier for critical infrastructure requiring reliable signal integrity. Their offerings support a broad spectrum of RF applications, from basic connectivity to advanced test setups.

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

Multi-Polarized antennas for Land Mobile Radio, Indoor & Outdoor Networks, Home Wireless, Mining Communications, Remote Monitoring, HAM & Scanner, Cellular, WiFi, Wimax, M2M, GPS, LTE, and GSM.

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.

Details Amphenol's extensive product line, encompassing electrical, electronic, and fiber optic connectors, alongside coaxial and flat-ribbon cable solutions. The company designs, manufactures, and markets these interconnect systems globally, serving various communication network requirements. Their offerings support end-to-end connectivity, crucial for modern broadband infrastructure. Emphasizes the company's role as a major provider of components vital for reliable signal transmission in diverse applications. Products like _LMR(R) coaxial cables_ and various _RF connectors_ are essential for amateur radio installations, ensuring low loss and robust connections for antennas and transceivers. The focus on high-performance interconnects directly benefits hams constructing or upgrading their stations. Amphenol's broad portfolio includes specialized connectors and cable assemblies, meeting rigorous technical specifications for both commercial and amateur radio use.

Amateur Radio Coaxial Antennas by G3TXQ

Maxcon makes and sells Amateur Radio Antennas. Double extended Zepp antenna, multiband dipoles, bazooka antennas, and VHF Jpole, made in USA

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

Amateur Television (ATV) operations involve transmitting and receiving live or recorded video and audio signals over amateur radio frequencies. Unlike narrow-band modes, ATV utilizes a wider bandwidth to convey video information, often requiring specialized transceivers, antennas, and signal processing equipment. This mode allows hams to share visual content, demonstrate projects, or conduct video conferences, typically on VHF, UHF, and microwave bands due to the bandwidth requirements. The SwissATV resource focuses on the technical aspects and community engagement surrounding ATV within Switzerland. It covers topics relevant to setting up ATV stations, understanding signal propagation at higher frequencies, and participating in local ATV activities. The site serves as a central point for Swiss ATV operators to exchange knowledge and coordinate transmissions, fostering the growth of this specialized amateur radio mode.