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The 144-430 portable j-pole antenna is designed for amateur radio operators seeking a lightweight and efficient solution for VHF and UHF communications. This antenna is particularly useful for portable operations, allowing hams to set up quickly in various locations while maintaining excellent performance. Constructed from readily available materials, it can be easily homebrewed, making it an ideal project for both beginners and experienced operators alike. The j-pole design offers a simple yet effective configuration that provides a good match across the 144 MHz and 430 MHz bands. Its vertical polarization and omnidirectional radiation pattern make it suitable for local communications and simplex operations. This antenna can be deployed in various environments, whether in the field or at home, and is well-suited for mobile applications. With proper construction techniques, operators can achieve optimal performance, enhancing their ability to make contacts during contests or casual QSOs.

Operating a handheld transceiver (HT) while bicycle mobile presents a significant challenge due to the lack of an effective ground plane on a bicycle frame. This project addresses that issue by providing construction details for a 2-meter antenna, specifically adapting the _ARRL Hints and Kinks_ design by Charlie Lofgren, W6JJZ, known as the "Bike 'n Hike Special." The antenna is designed to function efficiently on the 144 MHz band, offering a practical solution for portable VHF communication. The design emphasizes simplicity and portability, crucial for mobile operations where space and weight are at a premium. It details the necessary components and assembly steps, allowing amateurs to build a functional antenna that overcomes the inherent limitations of a bicycle as a radio platform. The original concept was published in the ARRL's well-regarded collection of practical amateur radio solutions. This antenna project enables bicycle mobile operators to achieve improved signal performance compared to a stock HT rubber duck, facilitating more reliable contacts while on the move. It represents a straightforward approach to enhancing VHF communications for active hams who combine cycling with their radio hobby.

Explains what amateur radio entails, detailing its dual role as a hobby and a public service, enabling communication among licensed operators using diverse radio equipment for self-training, recreation, and public service. It clarifies that ham radio operators require a government license, regulated globally by the ITU via the IARU, and outlines the privileges and responsibilities that come with operating an amateur radio station, including restrictions against commercial use and broadcasting to the general public. The resource then enumerates various activities hams engage in, such as worldwide HF communication, local VHF/UHF contacts, QRP operation, Packet Radio, Amateur Television, Slow Scan TV, contesting, and satellite communications. It also covers emergency and volunteer services, traffic handling, and the process of becoming a licensed amateur radio operator in the United States, mentioning local clubs, Elmers, and self-study as preparation methods for the FCC multiple-choice test.

Over 25,000 amplifiers and sub-assemblies were produced by Angle Linear for the communications industry over a 40-year period. The company specialized in **high-linearity RF products**, focusing on preamplifiers, bandpass filters, and receiver multicouplers. Specific product lines included PHEMT and GaAs FET preamplifiers, offering both quadrature and single-ended configurations for various signal levels. The offerings encompassed coaxial and combline bandpass filters, along with integrated filter-preamplifier assemblies. The company also provided custom RF assemblies, addressing applications such as MRI preamplifiers, passive radar, and EME (moon bounce). Their product range covered VHF and UHF frequencies, including specific designs for 2m, 70cm, and 23cm bands, often featuring high IP3 performance. Technical documentation, such as filtering application notes and duplexer theory, was also associated with their product offerings.

Operating on the HF bands, Kenwood's TS-990S and TS-890S transceivers represent their flagship offerings, providing advanced features for DXing and contesting. My personal experience with Kenwood gear, particularly the TS-590SG, confirms their reputation for solid receive performance and clean transmit audio, often noted in pileups. The TS-590SG, a popular choice for many hams, delivers reliable performance across the HF and 6-meter bands, making it a versatile station centerpiece. For VHF/UHF enthusiasts, the TH-D75A tribander offers 144, 220, and 430 MHz capabilities in a portable form factor. This handheld unit integrates D-STAR and APRS functionalities, appealing to operators who value digital modes and location-based services on the go. The inclusion of 220 MHz, a less common but valuable band, expands its utility for regional communications and specialized nets. Kenwood's enduring presence in the amateur radio market, dating back to 1955, underscores a commitment to quality and innovation. Their product range, from high-end base stations to feature-rich portables, continues to support a wide array of operating styles and technical requirements within the ham community.

WiNRADiO Communications, a division of Radixon Group, was established in 1996 to commercialize extensive research in radio communications. The company specializes in integrating radio and computing technologies, offering a diverse product range for government, military, security, and amateur radio enthusiasts. Their product line includes the WR-G65DDCe 'EXCALIBUR Sigma' HF/VHF SDR receiver, noted for its capabilities, and the G31DDC EXCALIBUR, recognized for its price/performance ratio in shortwave listening with improved AMS and Noise Blanker features. The company also produces the G39DDC series EXCELSIOR for serious monitoring, WR-G526e/G527e/G528e modular SDR solutions for high-performance applications like phase-coherent direction finding, and the low-cost WR-G305e/G305i VHF/UHF receivers. Professional counterparts, the WR-G315e/G315i, support APCO P25 decoders and trunking options. WiNRADiO's offerings extend to the PFSL-G3 field strength logging system for mobile signal coverage, advanced multichannel telemetry systems like the MS-8323, and specialized antennas such as the AX-31C Log-Periodic and AX-81S active HF antenna. DRM decoder software is available for G3 Series receivers, enabling clear reception of DRM broadcasts. The WSS-420 Weather Satellite Receiving System and various antenna rotators are also part of their product ecosystem. WiNRADiO supports multiple operating systems, with MacRadio for Apple Macintosh users and LiNRADiO for Linux developers, providing drivers and network receiver solutions like the RLX-810.

Demonstrates adapting the _Moxon rectangle_ antenna design for 2-meter VHF operation, highlighting its unique characteristics for specific applications. It details how the antenna's small size and distinctive far-field pattern, typically associated with HF, can be effectively utilized on VHF. The resource provides modeled dimensions for three different element diameters (1/4", 1/2", 1") and discusses the necessary adjustments to maintain optimal performance, such as gap spacing and element lengths, to achieve a 50-Ohm feedpoint impedance. The article presents predicted performance data, including gain (dBi), front-to-back ratio (dB), and feedpoint impedance (R, jX) across 144, 146, and 148 MHz. It analyzes free-space azimuth patterns and discusses the antenna's behavior when horizontally and vertically polarized over ground, including its suitability for fixed installations, repeater applications, and even satellite communications. Construction considerations, such as bending elements and maintaining critical gap distances, are also addressed. Furthermore, the content explores advanced configurations like using two back-to-back rectangles for broader coverage and a crossed-Moxon setup for circular polarization, suggesting potential for urban communication and satellite work. The author, _L. B. Cebik, W4RNL_, emphasizes the Moxon's strengths in broad bandwidth, wide beamwidth, and high front-to-back ratio, rather than maximum gain.

The resource provides detailed information about a five-band indoor magnetic loop antenna designed for amateur radio operators. This antenna is capable of operating on the 20, 17, 15, 12, and 10 meter bands, making it a versatile choice for various HF communications. Constructed from a single 3-meter length of 22 mm copper tube, the design emphasizes compactness and efficiency, which is particularly beneficial for operators with limited space. The page includes insights into the construction process, tuning, and operational tips, catering to both novice and experienced users. In addition to the technical specifications, the resource also discusses the advantages of using a magnetic loop antenna indoors, such as reduced interference and improved performance in urban environments. It serves as a practical guide for those interested in building their own antenna, offering a straightforward approach to antenna design and construction. Overall, this resource is a valuable addition to the toolkit of amateur radio enthusiasts looking to enhance their station with an effective indoor antenna solution.

Some tens of very special audio files recorded during amateur radio activities like aurora traffic, meteor scatter, communications with ISS crew and the sound of various transmission modes that you can hear on HF and VHF bands

Australian dealer, HF linear amplifiers, power supplies, baluns, HF UHF yagis and verticals including multiband HF verticals.

Over 40 years of experience inform the reviews and commentary presented on Dave's Radio Receiver Page, covering a wide array of radio receivers and transceivers. The resource details specific models such as the **ICOM IC-R8600** SDR Communications Receiver, which is lauded as Icom's best wide-band receiver, even surpassing the IC-R9500 in performance. Other notable reviews include the ICOM IC-7300 HF Transceiver, highlighting its direct sampling SDR technology and spectrum scope capabilities, alongside numerous models from Japan Radio Co. (JRC), Kenwood, Yaesu, and various portable shortwave receivers. The content provides practical insights into the performance and characteristics of each radio, often drawing comparisons between models. For instance, the early issues with the AOR AR7030 receiver's Bourns mechanical encoders are thoroughly documented, including AOR's eventual switch to higher-quality Alps encoders. The page also features reviews of antennas like the MFJ-1026 Noise Canceling Signal Enhancer and various power supplies, offering a holistic view of radio monitoring setups. The author's "2 ear / 2 eye method" emphasizes real-world listening experiences over laboratory measurements, providing a unique perspective on equipment utility.

Presents the design and construction details for a VHF bicycle-mobile antenna, originally published in QST. The antenna utilizes a modified _Arrow J-Pole_ design, adapted for portable operation on a bicycle frame. Performance characteristics include a reported **1.5:1 SWR** across the 2-meter band, demonstrating effective impedance matching for typical handheld transceivers. Construction involves readily available materials, emphasizing lightweight components suitable for mobile deployment. The document provides a parts list and step-by-step assembly instructions, detailing the radiator and ground plane element lengths for optimal resonance at 146 MHz. Mechanical considerations for mounting on a bicycle are also addressed. The resource covers practical aspects of integrating the antenna with a bicycle, including cable routing and securing methods. It offers insights into achieving reliable VHF communications while operating in a mobile, low-power environment, making it relevant for field day activities or casual portable operation.

Kv5r Understanding NVIS Antennas and Propagation. This article is not intended to be a complete primer on HF radio propagation or emergency communications.

Automatic Link Establishment (ALE) is a digital signaling protocol enabling HF radio stations to automatically establish communication links, crucial for emergency and disaster relief operations. HFLINK serves as a central international resource for ALE High Frequency Communications, HF Selective Calling (SELCALL), and general HF interoperability. The platform provides extensive information on ALE operation, including frequency networks, band plans, and software like _PCALE_ for amateur radio integration. It also documents significant events such as the _HF Interoperability Exercise (HFIE)_ and the _Global Simulated Emergency Test (GlobalSET)_, which allow ham operators to gain real-world experience in interoperable HF communications, often using specific frequencies like the USA 5 MHz ALE simplex frequency 5371.5 kHz USB. The site features articles on antenna types popular among ALE users, such as autotuners and broadband antennas like the _T2FD_ and the Broadband Butterfly Terminated Dipole (BBTD).

Broadcastify currently hosts 7,266 live public safety radio feeds, providing real-time scanner audio for police, fire, and EMS operations. The platform aggregates transmissions from various emergency services, allowing users to monitor local dispatch and response activities across numerous geographic areas. It functions as a centralized hub for streaming publicly accessible radio traffic, distinctly separate from amateur radio operations or traditional _DXing_ pursuits, focusing instead on unencrypted public safety communications. The resource primarily focuses on public safety radio systems, which typically operate on VHF/UHF frequencies, often employing trunked radio system architectures. It does not involve amateur radio bands but rather provides direct access to publicly available emergency service communications. The content is organized into categories like Top Feeds, New Feeds, and Official Feeds, facilitating navigation through its extensive catalog. Broadcastify's utility stems from its efficient aggregation and streaming infrastructure, offering a direct link to local emergency dispatch and response. The platform also details its operational mechanics and lists official providers, indicating a structured approach to content sourcing and distribution.

Professional antennas in MF, VHF, UHF and SHF frequency range for military applications, civil-professional market, mobile communications, radioamateurs and antennas for special applications - EMC, radiomonitoring, etc.

MQ-1 four band HF beams 20,15,10,6 meters MQ-2 six band HF beams 20,17,15,12,10,6 meters, beam antennas and Hybrid Quad antennas

Point to Point hf ionospheric communications analysis and prediction program

In 1999, W5GVE presented a detailed construction article for a 2-meter _DDRR_ antenna, specifically designed for mobile operation. This unique antenna, a Directional Discontinuity Ring Radiator, offers a compact footprint, making it suitable for vehicular mounting where traditional quarter-wave verticals might be impractical. The design emphasizes ease of homebrewing, utilizing readily available materials and basic workshop tools, allowing radio amateurs to build an effective mobile antenna for the 144 MHz band. The article provides insights into the antenna's performance characteristics, noting its low profile and potential for reduced wind loading compared to taller mobile whips. W5GVE's experience with the DDRR design suggests it can provide reliable communications on the 2-meter band, even in challenging mobile environments. The construction details include specific dimensions and assembly steps, guiding the builder through the process of creating a functional antenna. This project offers a practical alternative for hams seeking a discreet yet effective 2-meter mobile antenna, potentially achieving **3 dB** gain over a standard mobile whip.

The 6 Band Inverted L Antenna MK3 is a versatile multiband antenna designed for amateur radio operators. This antenna covers 160m, 80m, 40m, 20m, 15m, and 10m bands, making it suitable for a wide range of HF communications. The design is based on a W3DZZ configuration, incorporating traps for optimal performance. The MK3 version features a sturdy 5/8th CB mast, replacing the original timber mast, which enhances durability against harsh weather conditions. The antenna's construction allows for effective operation, particularly on the 40m band, where it has been successfully used to contact distant locations including ZL, VK, and Antarctica. Constructing this antenna requires careful attention to detail, especially regarding the radials and grounding. The traps resonate at specific frequencies, and additional resources are available for building coaxial traps. The antenna is designed to work efficiently without an ATU on the lower bands, while higher bands may require tuning. This project is ideal for both beginner and intermediate operators looking to enhance their station with a reliable multiband antenna.

HF Communications Analysis and Prediction Tools for Amateur Radio and communications professionals. Featuring: WinCAP Wizard, Beacon-Time Wizard, GeoAlert-Extreme Wizard, ID Wizard, KTS Clock Screen Saver, NERDAlert 2000

Manufacturers and distributors of coaxial surge protectors, coaxial switches, insultators, HF fixed wire antennas

Understanding high-frequency (HF) skywave propagation is crucial for amateur radio operators seeking to optimize long-distance communications. This resource details the fundamental principles of HF radio propagation, including the properties of electromagnetic waves, the characteristics of various HF bands, and distinct propagation modes such as skywave, ground wave, and line-of-sight. It places significant emphasis on the ionosphere's pivotal role in refracting HF waves, explaining how solar activity directly influences ionospheric conditions and, consequently, propagation paths. The resource integrates real-time monitoring capabilities, featuring dynamic charts and data from DX clusters, WSPRnet, and the Reverse Beacon Network, which allow users to track current band activity and propagation conditions globally. It also delves into advanced topics like Near Vertical Incidence Skywave (NVIS) and gray line propagation, providing insights into ionosonde data and various propagation prediction models. The site presents a detailed analysis of solar-terrestrial interactions, geomagnetic indices, and space weather phenomena, illustrating their direct impact on HF communication reliability. Practical tools and applications are highlighted, including real-time QSO planners, online Maximum Usable Frequency (MUF) maps, and alerts for solar flares or geomagnetic storms. The guide systematically breaks down complex concepts into accessible chapters, offering a structured approach to learning about ionospheric regions, diurnal and seasonal effects, and the interpretation of propagation indicators like foF2, MUF, and Lowest Usable Frequency (LUF). This makes it a robust reference for hams aiming to deepen their technical understanding and improve operational effectiveness.

RF engineering solutions, HF VHF antenna systems and radio communications equipment.

Presents the detailed construction of the _FLA25HV_ antenna, a specialized array optimized for Earth-Moon-Earth (EME) communications on the 2-meter band. This resource provides schematics and practical insights into building a high-gain antenna system capable of reflecting signals off the lunar surface, a challenging but rewarding aspect of amateur radio. It covers the mechanical and electrical considerations essential for achieving the precise pointing and signal strength required for successful moonbounce contacts, often yielding **20 dB** or more gain. Amateur radio operators pursuing EME operations require robust antenna systems and precise tracking capabilities. The FLA25HV design addresses these needs by focusing on element spacing, impedance matching, and structural integrity to withstand environmental factors while maintaining critical alignment for lunar reflections. Such systems are crucial for making contacts over distances exceeding **768,000 km**. This personal page serves as a practical guide for hams interested in constructing their own EME arrays, offering a glimpse into the technical dedication involved in pushing the boundaries of VHF/UHF propagation.

The following frequencies are assigned to datacommunications in the HF bands within the UK By RSGB data communications committee information.

Loop antennae have been used from ELF to UHF since the beginning of radiocommunications. At low frequencies, the main problem for loop antennae is to have enough sensitivity; the antenna being very small respect to the wavelength the collected energy is also small. To increase the output level the loop may be made resonant, so loosing it%u2019s intrinsic aperiodic characteristics.

HD Communications Corp specializes in **RF and microwave amplifiers** engineered for demanding communication, defense, and industrial applications. Their product line includes precision-built, high-power solutions, along with RF connectors, filters, HF cables, and various accessories. The company also supplies tower hardware, valves, and tubes, catering to a broad spectrum of radio frequency infrastructure needs. Beyond amplifiers, HD Communications offers a range of **RF filters**, including low-pass filters, antenna filters, and solutions for RFI/TVI mitigation. Their inventory encompasses essential components like coaxial cable and various connector types, supporting both amateur radio and professional installations. The company operates as a manufacturer and vendor, providing direct sales of its specialized RF products.

Operating Slow Scan Television (SSTV) on Apple macOS systems requires specialized software to encode and decode images for transmission over amateur radio frequencies. MultiScan 3B was an application designed for this purpose, enabling Mac users to engage in SSTV communications. It supported various popular SSTV modes, including Robot Black & Color, Scottie, Martin, PD modes (P3, P5, P7), and AVT, catering to a wide range of operational preferences and compatibility requirements within the SSTV community. The software's capabilities extended to both transmitting and receiving pictures, offering flexibility in how images were processed. Users could select regular, narrow, QRM, and narrow+QRM modes, allowing for adaptation to different band conditions and signal environments. This feature was particularly useful for mitigating interference and optimizing image quality during transmissions on HF bands. MultiScan 3B was built to run on Mac OS X 10.6 and later versions, providing a dedicated solution for Mac users interested in this classic digital mode. Its support for multiple modes and operational settings made it a versatile tool for SSTV enthusiasts.

Olivia MFSK digital communications are becoming popular in amateur radio because Olivia is one of the most robust methods of text keyboarding, that can perform superbly for long distance communications. Olivia frequencies, format and software

The **HFRadioSales.au** resource provides a commercial outlet for amateur and commercial radio operators seeking HF SSB equipment and related services. It focuses on the Australian market, offering new and refurbished transceivers, antennas, tuners, and a wide array of spare parts for brands like Codan, Barrett, and Qmac. The site details its role as a licensed dealer for new Barrett Communications and Codan radio and antenna systems, including specific models such as the Barrett 4050, 2050, and 950, and Codan Envoy and NGT series. This platform supports various applications, including vehicle, 4WD, outback, marine, and base station setups, catering to networks like HF Radio Club, VKS737, and RFDS. It also features commercial-grade antennas from Bushcomm, such as the BBA100C and SWC100, available for fast shipping from their Queensland warehouse. The site includes an FAQ section with general information on mobile HF communications in Australia and timelines for specific transceiver models.

A 2m Moxon antenna project, designed for the 145 MHz amateur radio band, provides a compact, directional solution for VHF communications. This resource details the construction process, specifying materials like PVC pipe for the frame, copper wire for elements, and a SO-239 connector for the feedpoint. The design emphasizes ease of build for hams seeking a gain antenna with good front-to-back ratio for local ragchewing or contesting. The project outlines precise element lengths and spacing, crucial for achieving the desired impedance and radiation pattern. It includes a visual representation of the antenna's dimensions and assembly, allowing for straightforward replication. The Moxon's inherent characteristics offer a practical alternative to larger Yagi arrays, particularly for portable operations or restricted spaces, while still delivering effective directivity and gain.

One of the most useful antennas in the repertoire is the Marconi or quarter wave grounded vertical antenna. Its invention made it possible to halve the length of antennas, simplifying communications, especially at HF and below.

The **2M Moxon antenna** design presented operates at 144 MHz, providing a compact, directional solution for VHF communications. Construction involves aluminum tubing for the elements, with specific dimensions for the driven element and reflector to achieve optimal performance. The design aims for a good front-to-back ratio and a relatively low SWR across the 2-meter band, making it suitable for portable or fixed station use where directivity is beneficial. Element lengths are critical for proper resonance and pattern. The driven element measures approximately 38.5 inches, while the reflector is slightly longer at 40.5 inches. Spacing between the elements is 12 inches, forming the characteristic Moxon rectangle. This configuration yields a gain of about 5.5 dBi and a front-to-back ratio exceeding 20 dB, which is advantageous for reducing interference from unwanted directions. Feedpoint impedance is close to 50 ohms, allowing direct connection to coaxial cable without complex matching networks. The antenna's lightweight structure, typically under 2 pounds, facilitates easy deployment and rotation, making it a practical choice for field operations or as a compact home station antenna.

Mobile antenna placement presents unique challenges for the amateur radio operator, often requiring compromises between RF performance and mechanical considerations. This resource from KV5R.COM offers practical insights into achieving effective installations, drawing on real-world experience with different vehicle types. It details how factors like ground plane availability, proximity to vehicle structures, and antenna type (e.g., **HF mobile**, **VHF/UHF mobile**) influence signal radiation patterns and overall system efficiency. The author discusses common scenarios, from sedans and SUVs to trucks and RVs, highlighting the impact of mounting locations such as the trunk lip, fender, or roof. Specific attention is given to minimizing RF interference and maximizing radiated power, crucial for reliable mobile communications. Understanding the interaction between the antenna and the vehicle's metallic body is key to a successful mobile setup, and this content provides a solid foundation for making informed decisions.

The YB7ZGP Pamaton Repeater operates on a frequency of 146.76 MHz, serving the Martapura District in Banjar, South Kalimantan, Indonesia. This VHF repeater provides local communication infrastructure for amateur radio operators in the region. The repeater's operation is managed by Syah Riyan, indicating a local amateur radio enthusiast or group maintains the station. Repeaters like YB7ZGP are critical for extending the range of VHF/UHF communications, allowing handheld and mobile transceivers to communicate over greater distances than line-of-sight. The 146.76 MHz frequency falls within the 2-meter band, a popular segment for local and regional amateur radio traffic, often utilized for emergency communications and general ragchewing. Information regarding the _Pamaton Repeater_ is presented on a blog platform, suggesting a community-driven effort to disseminate details about this local amateur radio asset.

Establishing a robust, interconnected communication infrastructure across challenging terrain, the Island Trunk System (ITS) provides a network of open amateur radio repeaters for general and emergency communications throughout Vancouver Island, surrounding waters, and parts of the lower mainland on the West Coast of British Columbia, Canada. This system, largely off-grid, relies on solar power and batteries, necessitating careful operation, especially during night hours and low solar charging seasons, to preserve its energy resources. Maintaining the ITS involves significant effort from many hams, who appreciate adherence to regulations, including proper station identification. The system hosts a weekly social net every Monday evening at 8 PM, welcoming all participants, and also supports a Vancouver Island Region Emergency Radio Net each Wednesday at 19:15. Experimental projects like the Newcastle Ridge webcams, linked via 5.8 GHz broadband backhaul over 206 km to Nanaimo and Comox, demonstrate the innovative spirit within the ITS community. A new VHF repeater, operating on 146.880 MHz with a 141.3 Hz PL tone, was installed in Tofino, expanding system coverage.

Deploying robust antenna infrastructure for both fixed and portable operations often requires specialized support structures capable of withstanding environmental stresses while providing optimal radiating element placement. SMC offers a range of solutions, including pneumatic masts and push-up masts, designed to facilitate rapid deployment and reliable long-term support for various antenna types. Their product line encompasses antenna mounts, poles, and complete antenna systems, addressing the critical need for stable and efficient RF communication. The company's offerings extend to HF antennas, including dipoles and _NVIS_ (Near Vertical Incidence Skywave) antennas, which are crucial for short-range regional communications on bands like 80m and 40m. These systems are engineered for durability and performance, ensuring signal integrity across diverse operating conditions. With over **65 years** of experience, SMC has established itself as a global manufacturer in this niche. Their product portfolio also includes antenna support towers, catering to more permanent installations requiring significant height and load capacity for multiple arrays.

The resource presents a detailed schematic for constructing a dual-band vertical antenna, specifically designed for operation on the 2-meter and 70-centimeter amateur radio bands. It illustrates the physical layout, critical dimensions, and component placement necessary for successful replication. Key elements such as the radiating elements, phasing sections, and feed point are clearly depicted, providing a visual guide for radio amateurs undertaking a homebrew antenna project. The diagram specifies the lengths for the VHF and UHF sections, indicating how these elements are integrated to achieve dual-band functionality from a single coaxial feedline. It also implies the use of common materials readily available to most experimenters, focusing on simplicity and effectiveness in its design. The visual format of a GIF image ensures direct access to the construction details without requiring extensive textual interpretation. This schematic serves as a practical reference for hams interested in building a compact, efficient vertical antenna for local and regional FM communications, offering a proven design for immediate implementation.

Presents a curated collection of newsletters dedicated to _Earth-Moon-Earth_ (EME) communications, primarily focusing on the 432 MHz band and higher microwave frequencies. The resource details various EME DX experiences and news contributions from operators like K2UYH (W6/PA0ZN), offering insights into successful moonbounce contacts and operational strategies. It serves as an archive of specialized content for those engaged in or interested in extreme weak-signal propagation via the moon. The newsletters provide practical information on achieving EME contacts, often including details on station setups, antenna arrays, and signal reports from challenging DX. For instance, operators might report achieving contacts over **750,000 km** round trip, demonstrating the feasibility of long-distance communication on UHF and microwave bands. The content differentiates itself by concentrating on the unique technical and operational aspects of EME, which contrasts significantly with terrestrial DXing, providing a specialized knowledge base for advanced amateur radio operators.

Codec2 is an open source low bit rate speech codec designed for communications quality speech at around 2400 bit/s. Applications include low bandwidth HF/VHF digital radio.

Showcasing a specialized product line, Advanced Receiver Research presents a comprehensive catalog of **low noise preamplifiers** and microwave **Gunnplexers**. The offerings span a broad spectrum of radio frequencies, from VLF, LF, MF, and HF bands up through VHF, UHF, and microwave, catering to diverse applications including amateur radio, commercial installations, and military systems. Their product range includes mast-mount preamplifiers, inline attenuators, power dividers, and various coaxial components. My own experience with similar low-noise front ends for weak-signal work on 2 meters and 70 centimeters underscores the critical role such components play in maximizing receiver sensitivity, especially when chasing distant DX or engaging in EME. The detailed product descriptions and technical specifications provided on the site allow operators to select the optimal preamplifier for their specific band and noise figure requirements, essential for improving signal-to-noise ratio. The site also lists specialized products for unique applications like Nuclear Magnetic Resonance (NMR) and Studio Transmitter Links (STL), demonstrating a depth of engineering capability beyond typical amateur radio fare. This breadth of offerings, coupled with clear ordering and warranty information, positions Advanced Receiver Research as a key supplier for high-performance RF components.

Presents a Brazilian online portal dedicated to **amateur radio**, **CB radio**, and shortwave listening (SWL) communities. The platform facilitates free classified advertisements for radio equipment, including HF, VHF, and UHF transceivers, antennas, and accessories. It also aggregates a substantial collection of technical articles from Brazilian amateur radio operators (e.g., PY2DJW, PY1LJ, PY1LL/4LC), covering topics such as CW training with RufzXP, balun importance, and radio wave characteristics. Furthermore, the resource provides extensive links to Brazilian ham radio sites, clubs, international organizations, and official ANATEL (Brazilian National Telecommunications Agency) documents regarding licensing, equipment homologation, and regulations. The portal features sections for user evaluations of transactions, a "Top Ten" list of most visited pages, and a calendar of past and upcoming ham radio events across Brazil, including "Feirinhas" (local swap meets) and "Encontros de Radioamadores" (hamfests). It also includes a directory of ham radio related businesses and services in Brazil, such as antenna manufacturers (Diex), QSL card printers (Arte Final), and repair technicians (PY2MOK). The site also offers propagation maps, DX cluster links (e.g., DX-SUMMIT), and satellite tracking tools, making it a central hub for Brazilian radio amateurs seeking to buy, sell, learn, or connect with the community.

Explore this high-resolution ITU Zones Map, a critical reference resource for amateur radio operators, international broadcasters, and telecommunications engineers. Originally established by the International Telecommunication Union – Radiocommunication Sector (ITU-R) Broadcasting Services Division (1999), this chart accurately divides the globe into 90 specific CIRAF zones. This authoritative visual guide is indispensable for planning High Frequency (HF) radio propagation, scheduling international broadcasts, and verifying locations for radio contests and awards. Distinct from the 40 CQ Zones, the ITU zoning system provides the official administrative framework used for global frequency management. This digitally enhanced version ensures maximum clarity of zone boundaries and numbering (e.g., Zone 28 for Central Europe), making it an essential tool for technical accuracy in logbooks and station management. It serves as a trustworthy standard for educators, hobbyists, and industry professionals alike.

The KP3AV Systems website offers a detailed listing of amateur radio repeaters across Puerto Rico, including operational frequencies and tones for VHF and UHF bands. It features sections dedicated to digital modes like DMR and C4FM, as well as information on FRS, GMRS, and MURS. The resource also includes articles on emergency communications protocols and provides access to Spanish-language manuals for various radio equipment. Recent content covers the new open-source FT2 mode for WSJT-X Improved, upcoming 60-meter band frequency allocations and power restrictions effective February 13, 2026, and discussions on 2-meter contacts with Desecheo Island from Puerto Rico. The site also presents U.S. amateur radio band plans and highlights local contesters like Manuel WP4TZ, offering practical insights into portable operations and contest participation.

Dish antenna and its theory and design for high performance applications such as satellite transmission and reception as well as microwave links. Parabolic Reflector Antenna: Dish Antenna The parabolic reflector antenna which is often called the dish antenna provides an antenna solution applicable for VHF and above where high gain and directivity are needed for all type of radio communications and radio reception.

Kenwood Ibérica's online presence details their extensive product line, including the NEXEDGE NXDN and DMR digital radio systems, alongside traditional analog offerings. The site categorizes transceivers by mode, such as HF / Todo Modo (All Mode), and portable/mobile VHF/UHF units, catering to various amateur radio operating preferences. This includes specific accessories like batteries, chargers, microphones, and programming cables, essential for maintaining and customizing radio equipment. The Spanish portal also highlights Kenwood's broader electronics portfolio, extending beyond amateur radio. This encompasses car electronics, featuring navigation and multimedia systems, as well as marine receivers and speakers. The product range covers everything from CD and CD-less car receivers to power amplifiers and DashCam/RearCam solutions, demonstrating the brand's diverse market reach. Beyond communications gear, the site presents home audio systems, including all-in-one receivers and portable party speakers. This breadth of offerings underscores Kenwood's long-standing presence in both the consumer electronics and two-way radio sectors, providing a centralized resource for product information and support.

A Ham Radio Newsletter dedicated to HF communications and the PACTOR user

Presents a comprehensive listing of VHF and UHF repeater systems operating within Ecuador, detailing their operational frequencies and geographical coverage. The resource includes specific entries for locations such as _Guayaquil_, Cuenca, and Manta, alongside their respective frequency pairs. For instance, the Cerro Azul repeater in Guayaquil operates on **6.760- T**, indicating a transmit offset, while the Sta. Elena system utilizes a 26.660 MHz transmit frequency. The data provides essential information for local and visiting amateur radio operators seeking to utilize regional repeater infrastructure. It delineates coverage areas using two-letter provincial abbreviations, such as AZ for Azuay and GY for Guayas, facilitating route planning and mobile operation. This compilation is particularly useful for those engaged in local communications or emergency preparedness within the Ecuadorian amateur radio community, offering a practical guide to available repeater assets.

The South African Radio League (SARL) serves as the national representative body for amateur radio in South Africa, holding membership in the International Amateur Radio Union (IARU). It actively promotes the hobby, coordinates national amateur radio activities, and provides essential services to its members, including advocacy for spectrum allocation and regulatory liaison with ICASA. The organization frequently publishes updates relevant to the ZS amateur community, such as "HF Update with ZS4BS" and reports on events like the "ZS6STN Field day." SARL supports various aspects of amateur radio, from contesting and DXing to technical experimentation and emergency communications. The league's website lists upcoming events and news, ensuring members stay informed about national and international amateur radio developments. Its focus encompasses all amateur bands, with recent updates highlighting HF activities. The league's digital presence, including its canonical URL _mysarl.org.za_, provides a central hub for South African hams. The site frequently updates with news, event schedules, and technical information, reflecting an active and engaged amateur radio community.