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Presents the VHFDX.EU web cluster, a specialized resource for VHF, UHF, and microwave DX spotting. It details the cluster's functionality, including real-time spot aggregation and a DXCluster Map interface for visualizing activity. The resource highlights its integration with the MMMonVHF backbone, ensuring a robust data flow for monitoring band openings and propagation events across higher frequencies. It also references reviews of the ON4KST and N0UK chat systems, which are frequently used in conjunction with VHF DX operations. The platform offers a mobile-optimized view for on-the-go access to DX spots, catering to portable and mobile operators. It further provides daily ES (Sporadic E) spot summaries, a critical feature for VHF operators tracking this specific propagation mode. The cluster serves as a central point for operators to share and receive information on rare grid squares, contest activity, and general band conditions above 50 MHz.

VK port-a-log is an Android logging app primarily for portable logging. It can be used for SOTA, WWFF or portable operations.

Presents a dedicated logging solution for amateur radio DXpeditions, addressing the unique operational demands of remote or temporary stations. This freeware Windows application provides essential tools for managing QSO data, ensuring accurate record-keeping during high-volume operations. The software supports efficient entry and retrieval of contact information, crucial for verifying DXCC credit and submitting contest logs. It streamlines the process of logging contacts, which is vital when operating from rare entities or during intense pile-ups, helping operators maintain focus on making contacts rather than complex data management. The application aims to simplify the logistical challenges associated with DXpedition logging.

Ham radio activities, from satellite operations, eme communications, dxing and contesting, qsling and direction findings, are just some of ham radio exciting activities

Introduction to WSPR beacons. Article describe WSPR2 and WSPR15 beaconing mode and include a frequency reference table for both WSPR modes

Marshall G. Emm, N1FN, meticulously examines iambic keying, dissecting its historical introduction in the late 1950s with transistorized electronic keyers and its purported advantages. The resource defines keying systems, electronic keyers, and various paddle types, including single-lever and dual-lever paddles, clarifying the distinction between iambic keyers and the iambic sending technique itself. It details the two main types of squeeze keying: true squeeze for alternating dot-dash strings and character insertion for specific elements within a character. N1FN critically evaluates the actual efficiency gains of iambic keying, referencing Chuck Adams, K7QO's, keystroke analysis. While a straight key to bug transition yields a 34.1% reduction and a bug to non-iambic keyer offers 16.1%, iambic keying provides only an 11% theoretical improvement. However, considering typical QSO text and Morse code's inherent optimization for common letters, the practical efficiency gain is estimated at a modest 4-6%. The article also highlights how iambic keying's reliance on precise timing gates can impose a speed limit, making it less effective above 40 WPM, where many operators revert to non-iambic methods or single-lever paddles.

Tape measurement yagi. The longest part is 530 mm, easy fit to your backpack. Very easy and fast deploy. Great for SOTA and portable operation. Can be used in horizontal or vertical polarization. Based on DK7ZB design

For radio amateurs seeking to verify contacts or identify stations from Tajikistan, the _Tajikistan EY Callbook_ serves as a dedicated online resource. This callbook, compiled and maintained by Irage M. Tursoon-Zadeh, _EY8WW_, offers a focused database of callsigns within the EY prefix region. It provides a practical utility for DXers and contesters aiming to confirm QSLs or prepare for operations involving stations in this specific geographic area, streamlining the process of identifying active hams. The resource's utility is particularly evident for those engaged in award programs like _DXCC_ or _WAZ_ where accurate callsign verification is crucial for credit. Unlike broader, worldwide callbooks, this specialized listing ensures high relevance and accuracy for its target region, reflecting the local expertise of EY8WW. Its direct focus on Tajikistan makes it a valuable, albeit niche, tool for operators with specific interest in Central Asian DX.

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.

A reference table of frequencies where you may find AM operations activity

Vapex Tech offers over **150 different battery products** tailored for diverse applications, including specific models for Icom, Kenwood, and Yaesu handheld transceivers. The product catalog details specifications for NiMH, LiPo, and LiFePO4 chemistries, providing crucial data on voltage, capacity, and discharge rates. Customers can browse by application, such as _Airsoft Batteries_ or _Model Control Batteries_, or directly by consumer battery types like AA and AAA cells. The resource presents a structured e-commerce platform where users can filter products by category, view detailed item descriptions, and proceed with online purchases. Each product listing includes high-resolution images and key technical parameters, enabling informed selection for specific radio equipment. Operational hours are clearly stated as 9am-5pm Mon-Fri and 9am-12pm Sat, with contact information including a sales email and phone number for direct inquiries. The site also features a "Latest News" section, indicating ongoing updates regarding product availability or company information.

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.

The World of LF, by G3YXM reference site for longwave operations. Introduction to operating on 136 and 501 Khz

The web pages of VU2PTT, Prasad Rajagopal, also AT2PTT, AT0PTT. Information on ham radio operations, Contest log book searches

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.

An interesting presentation of a real multiband Fan Dipole antenna, optimized for better DX operation performances, considering the terrain, position, DX destination path and other influencing factors

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.

Presents an Italian association, Club 27 Catania, which is affiliated with Protezione Civile FIR-CB. The resource indicates a focus on CB radio and various DX groups, including Papa Alfa Tango, Wisconsin Michigan, Charly Tango, Oscar Sierra, Big Time Operators, WAC Club, Azteca DX, and TX&RX Group. The page itself is a placeholder, stating "We’re getting things ready" and "Loading your experience… This won’t take long," suggesting future content will detail the club's activities and affiliations. The current state of the resource provides minimal information beyond its name and affiliations. It does not offer details on club events, membership, technical discussions, or operational specifics. The listed DX groups imply a focus on long-distance communications within the CB radio spectrum, but no specific results, comparisons of operating techniques, or practical applications are available on the present page.

The requested resource, identified by the title "Micamold XTR" and description referencing the _Micamold XTR-1_ transmitter manufactured in 1948 by MICAMOLD Radio Corp., is currently unavailable, returning a 404 error. This indicates the specific content detailing the vintage radio equipment, its technical specifications, or historical context is not present at the given URL. The original intent was likely to provide information on this particular piece of antique radio gear, potentially covering its design, operation, or restoration aspects relevant to collectors and enthusiasts of historical amateur radio equipment. The absence of the page means no technical details, schematics, or operational insights regarding the _XTR-1_ transmitter can be retrieved. Users seeking information on this specific "boat anchor" radio would need to pursue alternative sources or attempt to contact the original website owner directly, as suggested by the QSL.net error message. The QSL.net platform, which hosts over 30,000 individual amateur radio websites, provides free services but does not maintain the content of individual hosted pages.

Reviews of two types of poles used on portable operation to support wire antenna and accessories to plant poles in the ground by N4KGL

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.

NewLogOSH is a logging application for amateur radio operators, featuring integrated support for various digital modes including FT4, FT8, RTTY, and PSK. The software incorporates DXCluster connectivity and radio interfacing capabilities, allowing for seamless operation with transceivers. Its database is built within the SQLite environment, providing a robust and portable data storage solution for logging QSOs and managing station information. The program's architecture focuses on practical functionality for daily amateur radio operations. Operators can utilize NewLogOSH for contest logging, general DXing, and managing their station's contact history. The inclusion of FT4 and FT8 modes reflects current trends in digital communication, while RTTY and PSK support caters to established digital protocols. The DXCluster integration provides real-time spot information, aiding in DX hunting and propagation analysis. Its SQLite backend ensures data integrity and ease of backup, making it a reliable tool for maintaining comprehensive station logs.

Operational mode QRPp QRSS Running as an MEPT Manned Experimental Propagation Transmitter

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.

Presents a concise guide for Amateur Radio operators participating in Jamboree-on-the-Air (JOTA), an annual event connecting approximately 500,000 Scouts and Guides worldwide via ham radio. The resource details how to initiate a voice contact, including the use of "CQ Jamboree JOTA" and proper signal reporting with the RST system. It also outlines the typical exchange information, such as name, QTH, Scout rank, and age, encouraging participants to practice their responses. Authored by Bill Wetherill, N2WG, the brochure provides a practical phonetics chart and a comprehensive Morse code dictionary, including punctuation and prosigns like AR and SK. It clarifies rules for third-party operation under the direct supervision of a licensed operator, noting restrictions on international contacts without specific government agreements. Additionally, the guide lists recommended World Scout Frequencies for SSB and CW across 80, 40, 20, 17, 15, 12, and 10 meters, emphasizing courteous operating procedures. It includes a section on common Q-signals like QRM, QRN, and QSL, alongside the Amateur's Code, which stresses considerate, loyal, progressive, friendly, balanced, and patriotic conduct.

This resource, intended to present historical score records for the _ARRL International DX Contest_, currently displays a "Page not found" error. The page's original purpose was to document top scores and records for both Phone and CW segments of the contest, offering a historical perspective on competitive amateur radio operating. Without the content, no specific technical details regarding past contest results, callsigns of record holders, or score breakdowns can be extracted. The resource's current state prevents any analysis of score comparisons, operational strategies of top stations, or the evolution of contest performance over time.

The LU2EE Radio Club Tandil maintains a minimal web presence, primarily serving as a directory listing under the `qsl.net` domain. The resource itself offers no direct content, instead presenting an "Index of /l/lu2ee" page with a link to the "Parent Directory." This structure suggests a placeholder or an outdated web address rather than an active information hub, providing only the club's callsign and location. Without specific content, the resource does not offer technical details, operational results, or practical applications. It functions solely as a basic identifier for the _LU2EE_ club in _Tandil_, Argentina, without further elaboration on activities, membership, or technical contributions to the amateur radio community.

137.7 kHz QRSS beacon exciter is described, utilizing a single chip for operation on the 2200m amateur band. The design focuses on simplicity and efficiency for weak signal applications, providing a compact solution for generating QRSS signals. This project targets the DX portion of the band, enabling long-distance communication with minimal power output. The resource details the construction and functionality of the **QRSS beacon**, emphasizing its **low-power operation** and suitability for experimental amateur radio. It provides insights into the circuit's architecture and potential for integration into existing station setups. The design aims to offer a practical and accessible entry point for amateurs interested in weak signal modes on the LF/MF bands.

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.

Linux for shortwave and amateur radio monitoring. Supports popular SDR hardware and online streaming from KiwiSDR, WebSDR, and Spyserver sites. Articles about using Linux with your SDR devices.Skywave Linux, an innovative operating system, leverages cutting-edge technology for seamless access to radio signals globally. Ideal for regions with limited internet access, it effortlessly connects to a network of SDR servers, offering high-performance SDR operation without the need for extensive hardware. With pre-installed and configured SDR software, Skywave Linux simplifies signal discovery and operation for all users.

The mid florida dx association was formed in february 2005. to promote friendship and cooperation among amateur radio (wireless) operators primarily

715 days, 6 hours, 58 minutes, and 29 seconds of uptime are reported for the YSFReflector-Dashboard by DG9VH, which monitors the IT C4FM SUD / ITALY-SUD reflector. This dashboard, compiled on December 1, 2017, provides real-time operational statistics for the reflector, including system information, disk usage, and connected YSFGateways. The dashboard also features a "Last Heard List" and an "All Heard List," displaying callsigns, durations, and timestamps (Europe/Rome) of stations active on the reflector. These lists offer a quick overview of recent activity, which can be useful for tracking **C4FM** traffic. While the resource is titled "IZ7AUH-6 DX Web Cluster," the primary content displayed is a **YSFReflector** dashboard. This suggests the platform might serve a dual purpose, offering both traditional DX cluster services and monitoring for Yaesu System Fusion reflectors.

VP5X contest group website. VP5X is licensed to KY1V for contest operation from the Turks & Caicos Islands.

Amateur radio operators seeking local community and emergency communications involvement often look for active clubs. The Rock River Radio Club (RRRC) provides a platform for hams in Wisconsin to participate in weekly nets and monthly meetings, fostering camaraderie and operational readiness. Their activities include regular ARES/RACES nets, which are crucial for maintaining proficiency in emergency communication protocols and equipment. The club hosts weekly nets on both VHF/UHF and HF bands, allowing members to practice various modes and frequencies. These include a Monday evening net on the Juneau Repeater at _146.64 MHz_ (PL 123.0) and a Thursday evening net on the Knowles Repeater at _442.975 MHz_ (PL 123.0). An HF net operates on Saturdays at **3.947 MHz**, with an additional ARES/RACES net on Sundays at **3.967 MHz**. Monthly club meetings are held on the first Tuesday of each month at 7 PM in Randolph, Wisconsin, providing a consistent gathering point for members and prospective hams. The club also engages in public demonstrations, such as those at the Experimental Aircraft Association (EAA) Dodge County Chapter Fly-In, showcasing amateur radio to a broader audience.

Homebrewing portable antennas for field day operations

Presents the Sacramento Amateur Radio Club (W6AK), detailing its long-standing presence in the amateur radio community since 1914. The club's affiliation with the **ARRL** is highlighted, indicating its adherence to national amateur radio standards and participation in broader organizational activities. Content includes recent operational activities, such as participation at the Yolo County Fairgrounds, and social gatherings like meet-and-greets at East Portal Park, fostering member engagement. The resource also provides insights into the club's governance, listing current board members and their **call signs**, including the President Mike McDermott (KF6RUQ) and Vice President Jay Ballinger (N6SAC). Information on past elections and board position fillings offers transparency into the club's operational structure. The site functions as a central hub for club news and event announcements, reflecting its role in coordinating local amateur radio endeavors.

Amateur radio operations during heartquake in italy

Facilitates logging of amateur radio contacts directly within a web browser, enabling seamless operation across various devices including Windows, macOS, Linux, iOS, and Android. This web-based application stores all log data securely in the cloud, providing accessibility from any internet-connected location. It supports importing existing log data via CSV files, with future plans for _ADIF_ file import, and offers a robust QSL card generation feature, producing print-ready PDF files in standard 148mm x 100mm dimensions. The platform integrates with Japanese government databases to automatically populate callsign-related information such as station location and license issue dates, streamlining data entry. It also assists with JCC/JCG searches for accurate QTH logging. The service leverages SSL encryption for all communications and benefits from security oversight by certified information security professionals. Users can register using email/password or existing Facebook/Google accounts, and the beta version is currently available for free. The system has processed over **5,297,881** logs, with **28,369** logs recorded in the past 24 hours.

For amateur radio operators focused on **county hunting** awards, WD8LQB CountyLog offers a specialized logging solution for Windows. This software facilitates the logging of contacts specifically by county, a critical feature for those pursuing awards like the USA Counties Award. It includes functionality to export log data in **ADIF** format, ensuring compatibility with other logging programs and award submission systems. The program also provides access to the "Who's on the Air Database," a valuable resource for identifying active stations and planning county-specific operations. WD8LQB CountyLog is available in both a free limited version and a commercial version, allowing operators to choose based on their operational needs and budget. Its design prioritizes ease of use for county-focused logging, streamlining the process of recording contacts and managing the necessary data for award applications. The software's ability to integrate with external databases enhances its utility for real-time operational planning and post-contact verification.

The MMMonVHF database, curated by DL8EBW, currently lists 63,455 entries for VHF operators, providing a searchable resource for locating stations active on 144 MHz and higher bands. Operators can register their callsigns to be included, with specific criteria such as participation in _MS_ (Meteor Scatter), _WSJT_ modes, or _EME_ (Earth-Moon-Earth) operations required for inclusion in the `call3.txt` file. This resource facilitates VHF DX expeditions and contest planning by allowing users to identify potential contacts within a geographical area. The database supports various VHF/UHF operating modes, including those focused on weak signal propagation. Statistical data regarding the database entries is also presented, offering insights into the distribution of registered VHF activity.

This is a computer program for Amateur Radio transmission and reception using a computer and radio transceiver The program equips your computer with a one sentence at a time chat-mode for operation on the HF bands. You use it in the same way as you would Skype or cell-phone TXTing. This facilitates rapid-fire QSOs and especially makes nets easier by ZL2AFP

Indexes over 100 digitized amateur radio callbooks, primarily from the early to mid-20th century, providing a historical record of callsign assignments and licensee data. The collection facilitates research into past amateur radio operations, tracing callsign lineage, and identifying operators from specific eras. Each entry typically includes the callsign, licensee name, and geographic location as published in the original printed volumes. Users can browse the collection by publication date or utilize the search function to locate specific callsigns or names within the archived documents. The resource serves as a valuable repository for historical amateur radio data, supporting genealogical and operational research. Access to these scanned documents is provided directly through the Internet Archive platform, ensuring long-term preservation and availability of these historical amateur radio records.

1.5 dB of matched line loss can be calculated for a given transmission line using this online tool, which employs a model calibrated from empirical data. The calculator allows radio amateurs to input specific transmission line types, such as _RG-8_ or _RG-58_, and then determine the expected signal attenuation. This is crucial for optimizing antenna system efficiency and understanding power delivery to the radiating element, especially for HF and VHF operations where feedline losses can significantly impact performance. Beyond matched loss, the calculator also provides an estimate for mismatched loss if the Standing Wave Ratio (SWR) is specified. This feature helps operators quantify the additional power loss due to impedance discontinuities between the transceiver, feedline, and antenna, which is a common concern in amateur radio installations. Accurate loss calculations are vital for effective station design and for predicting actual radiated power. The tool's utility extends to various operating scenarios, from fixed station setups to portable deployments, aiding in the selection of appropriate feedline lengths and types to minimize signal degradation. Understanding these losses is a fundamental aspect of maximizing the effectiveness of any amateur radio antenna system.

This article is about a 4 element yagi VHF antenna designed to be easy to be assembled and suited for portable operations

The Associazione Radioamatori Italiani (ARI) Bergamo section provides a local hub for amateur radio operators in the Lombardy region of Italy. This resource details upcoming events such as the annual _Panettonata di Natale_ and important administrative updates like the 2026 membership renewal process. It also highlights special operating activities, including a commemorative radio activation for the 101st anniversary of the Gleno Dam disaster, which involved operators from both the Bergamo and Vallecamonica ARI sections. The site serves as a central point for local hams to stay informed about club activities and operational opportunities. Members can find information regarding payment methods for annual dues and event schedules. The Gleno Dam activation, for instance, is a significant event, demonstrating the club's engagement in historical remembrance through amateur radio. Such activities foster community spirit and provide opportunities for members to participate in public service and special event operations, often generating **hundreds of QSOs** and promoting the hobby.

It is our purpose to further the exchange of information and cooperation between members, to promote radio knowledge, fraternalism and individual operating efficiency

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

A VHF UHF mobile operation setup with APRS tracking by wd6cmu

remoteAudio is an multi platform Audio streaming application for Amateur Radio purposes. The most typical use case for this software is the remote operation of an amateur radio station. remoteAudio supports multiple users and multiple audio sources. At any time multiple clients can listen simultaneously on the same radio, although remoteAudio only allows one user to transmit.

To encouraging all aspects of Amateur Radio operation, including public service and radio experimentation for scientific improvement of the art.