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Monitoring real-time amateur radio activity is essential for DXers and contesters seeking rare contacts or tracking propagation. This online service aggregates DX spots from various **DX Cluster** networks, presenting them visually on a world map. Users can observe new spots as they appear, facilitating quick identification of active stations and potential openings. The platform offers filtering capabilities, allowing operators to narrow down displayed spots by specific bands such as 160m, 80m, 40m, 20m, 10m, and even VHF/UHF segments like 70cm and 23cm. Further refinement is possible by selecting the source continent of the spotter or the continent of the DX station, which assists in strategic operating. The service also includes a "Hot Now" list, highlighting currently active stations with recent spots. This dynamic display supports informed decision-making for pursuing **DX contacts** across different bands and geographical regions.

Solar power DIY kits. Homebrew your own solar power regulator, and power center.

The Highland Amateur Radio Association (HARA) centers itself in Hillsboro, Ohio.

A 2x3-foot laminated world map product is detailed, offering customization for amateur radio operators. Each map features two distinct views: one centered on the operator's specific station location and another precisely centered on its _antipode_. Countries are clearly labeled, complemented by a tabular listing of all countries. The map integrates a standard latitude/longitude grid alongside concentric circles that delineate distance increments radiating outward from the operator's QTH. Personalization includes the operator's name, callsign, and location printed directly on the map. This custom mapping service provides a unique visual aid for DXing and propagation analysis, allowing operators to quickly ascertain beam headings and distances from their station. The dual-view presentation, particularly the antipodal centering, offers a practical reference for understanding long-path propagation and identifying potential DX opportunities. The inclusion of distance circles and personalized station data makes it a tailored tool for daily operating and contest planning, distinct from generic world maps.

The Dilawri Cardiovascular Institute (DCI) is a prominent Canadian organization dedicated to advancing cardiovascular health through cutting-edge research, equitable patient care, and medical innovation. It integrates 16 core centers, including specialized units like the Centre for AI, Data Science, and Imaging, and the Centre for Heart Rhythm, to bridge research findings directly into clinical practice. Their mission emphasizes providing world-class cardiac care accessible to all patients, regardless of their geographic location, by employing disruptive innovation and creative strategies to reach individuals faster. The institute focuses on a team-based approach, ensuring patients receive the correct therapy at the optimal time for long-term well-being. DCI's commitment extends to continuous growth through education, pushing boundaries beyond standard care, and fostering a respectful, inclusive environment for both staff and patients. They lead industry collaborations to shape the detection, treatment, and management of heart disease.

Such kind of omnidirectional antenna gives the possibility to be QRV with horizontal polarisation, as commonly used for the CW and SSB section of the 2m band. This actual design shows a 1.3:1 bandwidth of about 150kHz, centered to 144.200MHz.

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

Providing solar on-line activity resources for the joy of solar science exploration

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.

A monoband delta loop antenna for the 7 MHz. This vertically polarized DX Antenna is a full wavelength sngle side antenna and has a total length of 42.3 meters (137,1 inch) Can be easily setup with a flag pole or fishing pole as center top mast. For optimal performance lower side should be at 2 meter above the ground. This antenna offers a low radiation angle and 1 DB Gain.

Examines Radio Frequency Systems (RFS), a manufacturer specializing in high-performance cable solutions for diverse communication infrastructures. The company, with over 120 years of heritage, focuses on designing and producing robust, long-life connectivity systems, including _low loss foam dielectric RF cable_ and _premium radiating cable_. RFS's product range supports critical applications in cellular networks, microwave antenna systems, and specialized installations within buildings and tunnels. The resource highlights RFS's commitment to innovation, addressing emerging industry standards like _FRMCS_ for railway communication and advanced fiber solutions for data centers. It also details the company's manufacturing capabilities in Hannover, Germany, emphasizing the quality and reliability associated with _Made in Germany_ products. The content covers various connectivity landscapes, from urban solutions for connected cities to private 5G credentials and future plans. Specific product categories include _fiber, power & hybrid cable_, and _low loss high power air dielectric RF cable_, showcasing their broad portfolio for complex RF environments.

J49I operated from Crete Island (EU-015, KM25PH) during the 2008 _CQ WW DX CW Contest_, focusing on multi-operator category participation. The station's activity centered on maximizing contacts and multiplier acquisition across various HF bands during the competitive event. Operators aimed to achieve a high score by leveraging the island's DXCC entity status. The team, comprising Greek and Italian amateur radio operators, utilized the J49I callsign for this specific contest operation. Their efforts contributed to the overall contest results for the 2008 CW segment, with logs submitted reflecting their performance from the European continent.

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.

The Hurricane Watch Net, Amateur Radio Serving the National Hurricane Center Since 1965. The HWN provides up to date tropical weather information for the Atlantic and Eastern Pacific. Subscribe for tropical weather email.

Over 1900 ARISS school events have been conducted since 2000, facilitating amateur radio contacts between students and ISS crew members. This resource details the Amateur Radio on the International Space Station (ARISS) program, outlining scheduled contacts, operational procedures, and application processes for educational institutions worldwide. It lists specific upcoming contacts, such as those with Lewis Center for Educational Research in California and Vauban, Ecole et Lycée français de Luxembourg, typically operating on a 145.800 MHz downlink frequency. The content also provides crucial guidelines for radio amateurs, emphasizing the importance of not interfering with scheduled school contacts and utilizing the crossband repeater for general QSOs when available. It clarifies crew availability for casual contacts, noting that astronauts are usually free during personal time, approximately one hour after waking and one hour before sleeping, and often on weekends. Constraints on scheduling, such as avoiding EVA weeks and specific crew rest periods, are also detailed. Furthermore, the resource includes historical statistics on direct versus telebridge contacts, QSL information, and links to related ARISS, AMSAT, ARRL, and NASA websites. It also provides information on applying to host an ARISS contact for schools and youth organizations in various regions, including the United States, Europe, Africa, the Middle East, Canada, Central and South America, Asia, and Australia.

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.

The Vintage Radio and Phonograph Society (VRPS) is a non-profit historical organization, incorporated in Texas, serving enthusiasts in the Dallas-Fort Worth area and surrounding regions. Its core mission revolves around the **preservation** and **restoration** of antique radios and phonographs, fostering a community for those with a general interest in early wireless technology and vintage audio equipment. The society actively supports the new radio/TV museum in Kilgore, TX, demonstrating its commitment to broader historical preservation efforts. Members engage in activities such as "Show and Tell" days, where they bring items for discussion, and participate in an annual convention. Events like the Spring Auction and the 2026 VRPS Convention, scheduled for October 23-25 at the Grapevine Convention Center, provide opportunities for members to connect, share knowledge, and acquire vintage pieces. The organization also highlights related events, such as the Houston Vintage Radio Association's 2026 convention.

Oklahoma City, OK

A home made portable vertical antenna, that with a single 1/4 wave counterpoise wire is possible to achieve less than 1.5:1 SWR on 40, 30, and 20 meter bands. It is basically a center load, shortened ground plain vertical antenna.

The OCFD Off-Center-Fed Dipole Antenna is an excellent multiband antenna that is relatively simple to construct, yet gets quite decent performance.

Coaxial cable stripping for PL-259 connectors requires precise measurements to ensure optimal RF performance and mechanical integrity. For RG-8X, the outer jacket is stripped 1/2 inch, the braid 5/16 inch, and the dielectric 1/8 inch, leaving the center conductor exposed. RG-58 preparation involves a 1/2 inch jacket strip, 1/4 inch braid strip, and 1/8 inch dielectric strip. These specific dimensions facilitate proper soldering and crimping, minimizing impedance discontinuities at the connector interface. Different coaxial cable types, such as RG-8 and RG-213, necessitate varied stripping lengths due to their construction. The _PL-259_ connector, a common UHF type, relies on these exact preparations for a secure fit and low-loss connection. Incorrect stripping can lead to high SWR, RF leakage, and mechanical failure, impacting overall station efficiency. The guide details these critical dimensions for several popular coax cables. Using a dedicated _coax stripper_ tool or precise measurements with a utility knife improves consistency.

An interesting article on end fed half-wave wire antennas with a couple of original experiments. Author illustrate the role of the QRP matchbox, and a 40/20 meter antenna with a center stub making it a large bandwidth antenna for 40 and 20. Includes also an 80/40 end fed with the typical coil to make it available on 80 merts band.

A home made end-fed half-wave antenna coupler with antenna lenght calculator and counterpoise calculator based on center frequency. Includes pictures and drawings along to antenna homebrewing instructions with a home made on air wound transformer

The Tri-pole antenna, a clever modification of a standard dipole, allows for dual-band operation by integrating a third element. This design effectively shortens the overall dipole length by 10 to 20 percent, simplifying antenna rotation and offering a compact footprint. KK4OBI's article delves into the operational principles, using a 6 and 10-meter Tri-pole as a primary example, and provides comprehensive instructions for constructing any Tri-pole antenna within the 6 to 15-meter range. Key to the Tri-pole's performance is its off-center feed, necessitating a common mode choke at the feed point for optimal tuning and reduced noise. The author outlines a methodical approach to determining element dimensions, starting with a vertical element frequency calculated as 0.47 times the sum of the desired upper and lower band frequencies. This calculation, along with K-values derived from trend lines, guides the initial lengths for the horizontal arms, demonstrating how a 10m-6m Tri-pole can achieve a total horizontal length 78% shorter than a conventional 10-meter dipole. Tuning and balancing are critical, with the article detailing adjustments to arm lengths and the vertical element to achieve balanced SWR values, as validated through 4NEC2 simulations. Radiation patterns are analyzed at various elevations, showing gains around 5.7 dBi and favorable take-off angles for DX contacts. Construction details specify aluminum tubing dimensions, U-bolts, and an SO-239 connector, emphasizing the importance of a ferrite-based choke for wideband operation.

Operating in the Caribbean, the Jamaica Amateur Radio Association (JARA) provides a central hub for amateur radio enthusiasts on the island. The association details its **repeater network**, including IRLP node 7673 and ECHOLINK access, alongside information on band activity and packet radio operations. Members can access specific documents like the JARA Membership Form and the JARA Disaster Plan, while general visitors can review the full JARA Regulations and learn about the club's history. The site features a photo album and outlines various radio activities, including what constitutes a JARA Field Day. It also provides essential resources such as the Reciprocal License Form and Jamaica Amateur Radio Regulations, crucial for visiting operators. The **WINLINK Project** and Radio Voice Procedure are also covered, offering practical guidance for communications. JARA maintains affiliations with international bodies like **IARU Region II**, ARRL, and RSGB, and lists important organizations such as SATERN 14.265, Jamaica Red Cross, and the National Hurricane Center. The website also includes links to other amateur radio clubs across North America, the Caribbean, and Central and South America, fostering regional and international connections.

This type of antenna is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It’s a dipole fed off center with a 4:1 balun at the offset feed point. The antenna shown covers 80, 40, 20 and 10 meters. The formula can also be used to adjust the overall length to cover more or fewer bands and the resulting overall length. 160-10m, 80-10m or 40-10 meters depending on your available space. Other bands will require a tuner.

Operating under the callsigns G1ORC, G4ORC, and M5ORC, the Oldham Amateur Radio Club (OARC) serves as a local hub for radio enthusiasts in Royton, Oldham, England. This RSGB-affiliated organization welcomes individuals with an interest in any facet of radio communication, fostering a community environment for learning and on-air activity. The club maintains an active calendar, detailing upcoming amateur radio events and specific courses hosted by OARC, providing a structured approach to engagement for its members. Club activities are centered at the No.1855 (Royton) Squadron Air Training Corps on Park Lane, a consistent meeting point for members. This physical location facilitates hands-on learning, equipment demonstrations, and social interaction among hams. OARC's commitment to the hobby is evident through its multiple transmitting licenses, enabling diverse operational experiences for its members across various bands and modes.

A 60-foot available space, for example, might necessitate a shortened multiband dipole array to cover 80, 40, and 15 meters effectively. This resource details the construction of such an antenna, combining full-size and coil-loaded dipoles on a single feedline. It addresses the common challenge of fitting multiple HF bands into restricted physical footprints, providing practical guidance for hams with smaller backyards or portable operations. The core of the offering is an interactive calculator that determines required loading coil inductance and dipole lengths for various amateur bands from 160m to 10m. Users input their available space, and the tool provides dimensions, coil turns, and an efficiency rating (Good or Fair) based on the antenna's electrical length relative to a quarter-wavelength. It also suggests suitable _PVC_ pipe diameters for coil forms. The article further illustrates a center feed-point assembly using an 18-inch section of 2-inch _PVC_ pipe, detailing eye-bolt spacing and coaxial connector installation. It emphasizes the importance of adequate spacing between parallel dipoles and offers customization options for the feed-point, including the addition of a _Balun_ for improved feedline isolation.

The Delta Amateur Radio Club (DARC) serves as a community organization for amateur radio operators in the Memphis, Tennessee area, providing resources and activities centered around two-way radio communication. The club maintains the W4BS repeater system, which operates on 147.060 MHz with a +600 kHz offset and a 100 Hz PL tone, facilitating local VHF communications. DARC actively supports the Amateur Radio Emergency Service (ARES), preparing members for public service and disaster response through training and coordinated drills. The club also hosts regular meetings and events, fostering camaraderie and technical skill development among its members. Membership in the Delta Amateur Radio Club offers opportunities for participation in various amateur radio activities, including field day operations and local nets. The W4BS repeater provides reliable coverage across the Memphis metropolitan area, serving as a critical asset for both daily ragchewing and emergency traffic handling. DARC's affiliation with the Amateur Radio Relay League (ARRL) ensures access to national resources and advocacy, reinforcing the club's commitment to promoting amateur radio and public service within the community. The club's focus on emergency communications strengthens local preparedness.

The Hurricane Watch Net (HWN) is an amateur radio organization dedicated to serving the National Hurricane Center and the public since 1965. It plays a crucial role in disseminating real-time tropical weather information for the Atlantic and Eastern Pacific regions. The HWN operates during hurricane events, providing updates and facilitating communication among amateur radio operators and emergency services. This network is essential for ensuring that communities are informed and prepared for severe weather conditions. In addition to its operational role, the HWN offers educational resources and outreach programs aimed at enhancing public awareness about hurricane preparedness. This includes providing access to tracking maps, storm surge information, and safety guidelines. The HWN encourages amateur radio operators to participate in its activities, fostering a spirit of community and collaboration in the face of natural disasters. By subscribing to their email updates, individuals can stay informed about active storms and receive vital safety information.

Building an End-Fed Half-Wave (EFHW) antenna from a kit, as detailed by Frank Bontenbal, PA2DKW, with process photos by Bob Inderbitzen, NQ1R, offers a practical approach for hams. This specific kit, a collaboration between ARRL and HF Kits, targets 10, 15, 20, and 40 meters, making it a versatile option for HF operations. Unlike a center-fed dipole, the EFHW is a half-wavelength antenna fed at one end, which simplifies deployment, particularly for portable use. The construction guide meticulously outlines the assembly of the 49:1 impedance matching network, crucial for transforming the antenna's high impedance (around 2,500 Ohms) to a transceiver-friendly 50 Ohms. Steps include preparing the enclosure by drilling holes for the coaxial connector and antenna connections, followed by the precise winding of enameled copper wire onto a toroid to create the transformer. The guide emphasizes careful insulation removal and soldering for reliable connections. Final assembly involves integrating a 100 pF capacitor for higher band compensation, soldering the transformer's primary and secondary sides, and conducting SWR tests with a 2K7 resistor or a half-wavelength wire. The document also provides examples of wire lengths for different bands, such as 16 feet for 10 meters or 66 feet for 40 meters, demonstrating the transformer's adaptability for various half-wavelength configurations.

The _G3TSO_ Mobile Antenna Page details construction and tuning methods for mobile antennas operating across **10 to 160 metres**. The content describes a Hustler-based design, optimized for RF performance and vehicle speeds, featuring centre loading. For optimal operation on various bands, the loading coil placement requires clearance from the vehicle body. Antenna resonance is critical for efficient mobile operation. A mobile antenna's base impedance may be as low as 27 ohms, requiring specific matching to achieve maximum radiation, as a minimum SWR at the transmitter does not always indicate resonance or maximum output. Tuning involves physical adjustment of antenna length to achieve resonance at the operating frequency. The _G3TSO_ page outlines a tuning procedure utilizing a low-power signal source and a field strength meter to identify maximum radiation before impedance matching. Loading coil placement, either at the base, center, or top of the antenna, influences radiation efficiency and mechanical stability for mobile installations. Centre-loaded whips, such as the Hustler design, offer a compromise between efficiency and stability, often for single-band operation. Helically wound antennas, including those for **28 MHz**, may present base impedances around 17 ohms, resulting in a 3:1 SWR at resonance. Low resistance grounding at the antenna base is also specified for optimizing performance and minimizing RFI during mobile operation. DXZone Focus: Mobile | Any | Antenna Tuning | HF

This article discusses suitable first HF antenna options for amateur radio operators with limited space. It recommends an Off-Center Fed (OCF) Dipole and a Vertical Dipole, detailing the installation processes, considerations for stealth and ease of setup, and the characteristics that make them ideal for newcomers. Safety warnings and maintenance tips are provided to ensure effective and secure operation.

The antenna I built was inspired by a portable delta loop designed by Doug DeMaw, W1FB. Given that I constrained myself to a 50-foot roll of speak wire, I scaled my antenna for the 20M band. Using the formula, 1005 divided by the frequency in megahertz, I calculated a total length of 71 feet (21.6 meters) for the center of the 20M band.

An ARRL Special Service Club. Meets every Tuesday at Portland Senior Center, 7 Waverly Ave., Portland, CT 06480

Ribbit is a novel digital text messaging mode for VHF/UHF communications for recreational and emergency use which radically increases the density of information transmitted by spectrum used. It leverages the computing power of the modern smartphone to increase the capabilities of any Handy Talkie without requiring any additional hardware or cable. A Ribbit message is fixed in duration at 1250 milliseconds. It is sent over audio modulation with a 2kHz bandwidth centered on 1.5kHz. It is preceded by 400ms of white noise to open analog squelch circuits.

A rotatable 40-meter dipole antenna designed and constructed to fit within backyard constraints. The project utilized two fishing poles attached to a fiberglass center pole, resulting in an easy-to-build, lightweight, and cost-effective antenna. Essential materials included fishing rods, a center support pole, mast support, and basic tools. Linear loading was implemented to achieve the necessary length for optimal performance. The antenna, which proved effective during the contest, is ideal for field days and additional contest bands. Assembly and installation were straightforward, showcasing the antenna's practicality and efficiency.

The article describes the construction of a 1:49 impedance transformer designed to match the high impedance (around 2500Ω) of an end-fed half-wave (EFHW) dipole antenna to the 50Ω impedance of a typical transceiver. The EFHW is a popular portable antenna due to its simple construction, but feeding it can be challenging compared to a center-fed dipole. The transformer was built using an FT240-43 ferrite toroid core, with 2 primary and 14 secondary windings for a 1:49 impedance ratio. A capacitor was added in series with the primary winding to improve performance at higher frequencies. The author compared versions with one and two cores, and found that 100pF worked best for the single core design while 200pF was optimal for the dual core transformer.

Online antenna calculator for a basic 3 elements yagi uda directional antenna. The described antenna design offers a front-to-back ratio of at least 20 dB, a gain exceeding 7.3 dBi, and a bandwidth (SWR < 2) of approximately 7% around the center frequency. It has an input impedance of 50 ohms when using a straight split dipole, which can be substituted with a folded dipole of the same length, increasing the impedance to 200 ohms. A matching balun is required for coaxial feeder connection, and the boom should be made of a dielectric material, like wood.

Discussion about laterally bent-end dipoles. Bent by percentage of length and fine-tuned by angling the bent ends.

AZIWORLD is a user-friendly tool for generating azimuthal maps of the Earth centered on any location. Compatible with Windows XP and later, it supports English and French. Maps can be saved in .bmp format for easy customization. AZIWORLD computes azimuths, distances, and geographical positions, integrating seamlessly with AZIPOINT for automatic antenna pointing. Linux/Ubuntu/Android users can run AZIWORLD via WINE or CROSSOVER. For optimal functionality, installing AZIPOINT alongside AZIWORLD is recommended.

The multiband tuned doublet, or center-fed Zepp, is a simple and efficient HF antenna that operates effectively across most amateur bands using a balanced parallel-wire feedline and antenna tuner. Unlike coax-fed dipoles, it tolerates impedance mismatches with minimal loss. By selecting suitable feedline and dipole lengths, one can achieve stable multi-band operation. While it doesn’t match monoband Yagis, it offers excellent performance, low cost, and broad coverage. Its radiation pattern and efficiency vary with frequency, but it remains a practical and versatile solution for HF operators.

DIY project of a QRP Balun. Using a high permeability ferrite rod and an old B&W dipole center insulator, he constructs a choke type balun for QRP use. The balun aims to create as much inductance as possible at HF, offering a high impedance to common mode currents

Since December 2020, the FCC no longer prints paper amateur radio licenses. Licensees must obtain official electronic copies by logging into the FCC's Universal Licensing System (ULS) with their FRN and password. Detailed instructions are available on the FCC website or by contacting the FCC Licensing Support Center.

The article by Guy Olinger, K2AV, published in the May/June 2012 National Contest Journal, introduces the Folded Counterpoise (FCP), a compact 516-foot single-wire counterpoise elevated at 8 feet, designed for 160-meter operations on small lots like 100x150-foot backyards. Originating from efforts to revive Top Band for W0UCE on a postage-stamp property, the FCP uses strategic folds to cancel ground fields within 33 feet of center, minimizing losses to 0.13-0.53 dB—outperforming sparse or on-ground radials by up to 15 dB in poor soil—while mimicking opposed radials for efficient feedpoint impedance. Paired with a critical 1:1 or 4:1 isolation transformer (e.g., trifilar on T300-2 toroid) to block common-mode currents on coax feeds, it delivers proven results: K2AV's #8 North America low-power contest score, 7+ dB gains at W4KAZ and K5AF, and over 10,000 global web hits for DIY instructions using bare 12 AWG wire and weatherproof enclosures. Ideal for acreage-challenged hams, the FCP also excels on 80 meters with scaled dimensions, offering a low-loss alternative where full radials are impractical

The LKJ Wednesday Night Special Antenna, designed by John Whiteman K5LKJ, is a compact 50-foot coil-loaded dipole for 80-meter operation, ideal for space-limited hams in residential areas. Using two 1-inch diameter PVC coils with 87 turns of #16 magnet wire each—placed 10 feet from the center—it tunes to 3.910 MHz for local nets like BVARC Rag Chew. Constructed with #14 wire, ceramic insulators, and Mini-8X feedline, it handles 1000W, performs well at low heights for NVIS, and requires a tuner for bandwidth. Collaborative tuning by club members ensured success.

A custom center hub for a Spiderbeam yagi antenna, enabling side-mounting on an existing mast. Challenges included structural instability, limited reach for assembly, and interference with a pre-mounted Spiderpole. A new hub using 40x40mm aluminum tubing provided strength, allowed side assembly, and supported fiberglass pole guy lines. The solution facilitated efficient installation and removal, delivering excellent performance compared to a SteppIR yagi.

This page provides information on how to design an Off-Center-Fed Dipole (OCFD) antenna, suitable for amateur HF bands like 80 meters or 40 meters. The antenna design allows for VSWR minima on multiple bands, making it a good choice for multi-band use. Learn how to create an OCFD antenna in either flat-top or inverted-Vee form using a single support. The page also offers tools to generate radiation patterns, VSWR charts, and antenna current diagrams for your specific antenna design, helping hams understand performance factors. Ideal for ham radio operators looking to build their own effective antennas.

When installing a mobile antenna, optimal placement significantly impacts performance. Factors such as gain, antenna type, ground plane availability, mounting style, and environment must be considered. Antenna designs, such as 1/4 wave and 5/8 wave, have distinct radiation patterns ideal for specific settings—urban areas or flat terrains, respectively. Ground plane size requirements differ by frequency, impacting effectiveness. Among vehicle mounting options, the car roof center provides the best ground plane and minimal obstruction, ensuring peak performance, especially at higher frequencies like 800 MHz.

This webpage caters to EMRFD owners, offering insights into building popcorn receiver band-pass filters with Ladpac programs and EMRFD Chapter 3 knowledge. Through practical experiments and Ladpac tools, the author explores coupling capacitors' impact on filter response and return loss optimization. The content emphasizes empirical approaches, encouraging builders to embrace experimentation and learn from mistakes. Detailed examples and workflow suggestions aid hobbyist-level designers in creating customized filters, fostering a deeper understanding of filter design principles.