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This document is a must read for anyone considering building a good low cost HF multi-band antenna system. The author combine in this document four important ingredients to produce simple but effective antenna system, like antennas of non resonant length, line attenuation, the transmatch and the balun
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North West CB Radio is a page with radio modifications’s, Local Portland’s Traffic info, Trucker things like CB slang, DX info and a forum. Also we host The Saturday Night Stomp Fest in the Portland area. Results are posted weekly.
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W1MX, the MIT Radio Society, stands as America's oldest college amateur station, providing a vibrant hub for MIT students, faculty, and staff interested in RF engineering, telecommunications, and radio science. The club, formerly known as 1XM, fosters a growing membership and hosts regular business meetings on the first Tuesday of each month at 7:30 PM ET, alongside weekly social gatherings every Friday at 7:00 PM ET in room 50-358. No prior radio experience is necessary to participate, and interested students are encouraged to attend a social meeting for a station tour and to learn about typical club activities. The society emphasizes experiential learning opportunities, actively seeking support to build a new and improved station at MIT. The club maintains a consistent presence in 50-358 during semesters and IAP, often extending into the summer, with the exception of club trips. Members can also access a dedicated webpage displaying the last 30 days of door activity, updating every five minutes, while a public frame shows the current door status and recent activity.
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The ZL1BPU Rotator Controller has been designed as an add-on unit for the popular Kenpro KR-400 and Yaesu G-400 rotators. The controller consists of a small circuit board which fits inside the rotator control box
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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.
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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.
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The TransWorld Antennas TW4040 The Adventurer Monobander™ is a portable HF antenna designed for rapid deployment in field operations, including **SOTA** and **POTA** activations. This manual details the antenna's assembly, tuning procedures, and operational guidelines for optimal performance on the 40-meter band. It outlines the specific components, such as the telescoping whip and base unit, required for proper setup. Instructions cover mast erection, radial wire deployment, and impedance matching to achieve a low **VSWR** across the designated frequency segment. The document also provides guidance on antenna orientation and environmental considerations for portable use. It specifies the antenna's power handling capabilities and physical dimensions when fully deployed and collapsed for transport.
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A presentation of the Yagi Antennas, and other interesting tid-bits by Brian Mileshosky. The document provides an in-depth exploration of the Yagi-Uda antenna, detailing its historical development, design principles, and performance characteristics. Originally described in the 1920s, the Yagi antenna features a driven element and parasitic elements, including reflectors and directors, which collectively determine its behavior. The document highlights how element lengths, diameters, and spacing influence gain, impedance, and directivity. It also discusses the antenna's reciprocal nature and presents data on typical gain values for various element configurations. Additionally, the text covers practical considerations, such as the construction of a "Tape Measure Yagi" for amateur use, and touches on related antenna types like dipoles and their application in Near Vertical Incident Skywave (NVIS) communication.
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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.
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President Karami Radio Society. Amateur Radio Club Station OD5RAK, Tripoli - Lebanon
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Guidelines for optimal speaker placement inside our ham radio shacks
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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
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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.
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Lido Radio Products specializes in **no-holes mounting solutions** for a wide array of mobile electronic devices, including amateur radio transceivers, smartphones, and tablets. Their product line features cup holders, vent mounts, and window mounts, designed to secure equipment without permanent modifications to a vehicle's interior. The company supports various brands such as Icom, Yaesu, Kenwood, Motorola, Hytera, and Vertex, catering to both amateur radio operators and land mobile users. My own experience with similar mounting systems for mobile operations confirms the utility of a secure, non-invasive setup. A stable mount prevents equipment from becoming a projectile during sudden stops or turns, a critical safety consideration for any mobile station. Lido's focus on specific radio brands suggests a tailored approach to fit and function. They also provide individual parts to customize existing mounts, allowing operators to adapt solutions to unique shack or vehicle configurations. This modularity is a significant advantage for hams who frequently reconfigure their mobile setups or integrate new gear.
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A project to implement a simple and efficient CW Keyer and a side tone generator with Arduino
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Discover the huge amount of components inside Compact Fluorescent Lights
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The dipole shown in this document is installed in an inverted Vee configuration, with two leg elements on each side held parallel to each other by 21cm spacers. The upper leg is for 40m and the lower leg for 20m. The spacers are made of 7mm plastic garden hose support for garden sprayers cut to 21cm.
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A manufacturer of standby and prime power generator sets for industrial, telecommunication, commercial, small business, mobile and residential applications.
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Jefferson Amateur Radio Club JARC was originally founded in 1956. We're located just outside of New Orleans, Louisiana in the suburb of Metairie
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The BTech DMR-6X2 dual-band DMR handheld radio is thoroughly reviewed, detailing its features and performance for amateur radio operators. This resource covers the radio's capabilities for both VHF and UHF frequencies, supporting Tier II DMR digital and FM analog modes. It highlights key specifications such as its **136-174 MHz** and **400-480 MHz** frequency ranges, CTCSS/DCS, DTMF, 2-TONE, and 5-TONE signaling, and its _digital simplex repeater_ function. The review provides a comprehensive unboxing experience, listing included accessories like two Li-Ion batteries (2100 and 3100 mAh), a programming cable, and a 37-page English user guide. It also specifies the radio's physical dimensions of 5.1 x 2.4 x 1.5 inches and weights of 9.9 oz with the 2100 mAh battery and 10.8 oz with the 3100 mAh battery, offering practical insights for hams considering this transceiver.
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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.
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The Superantennas MP-1 portable HF antenna is analyzed for its design and field performance, particularly its high-Q loading coil and 3/8-inch mounting. The review details the antenna's construction, including an 8-inch vertical section, a large-diameter loading coil tuned by a sleeve, and a 4-foot whip that disassembles into six rods for transport. Initial testing with the supplied 10-foot ribbon cable "ground plane" yielded poor SWR and RF hot conditions, indicating an inadequate ground system. Further experimentation with longer radials and resonant counterpoises for each band improved matching and eliminated RF hot issues, but introduced significant operational complexity. The author notes the difficulty in optimizing both counterpoise length and coil setting without an antenna analyzer, and the sensitivity of the MP-1 to counterpoise deployment. The review also discusses the recommendation to tune for maximum received signals rather than minimum SWR, often necessitating an external ATU due to the antenna's typical low impedance. The **MP-1**'s critical dependence on resonant counterpoises for effective operation, especially when elevated, is highlighted as a major drawback for portable use. The author ultimately sold the antenna, concluding that despite its sound technical design, its fussy nature and the need for extensive counterpoise management or an ATU detract from its portability and convenience compared to simpler, less expensive dipole solutions. The **Superantennas MP-1** is deemed a flawed portable antenna, requiring considerable effort to achieve its claimed performance.
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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.
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The SETI League, Inc., founded in 1994, focused on participatory science, developing technology to seek definitive answers to the question of extraterrestrial intelligence. The organization operated in five dozen countries across all seven continents, maintaining the quest for cosmic companions through the efforts of its 1500 members. Although the organization shuttered its virtual doors after thirty years in 2024, the website remains for educational and historical purposes, documenting past research and activities. Key technical resources include the _SETI League Mini-Manual_ for constructing a 12 GHz radio telescope under $200, and software like _SETIFox for Windows_ and _Radio Eyes_ for radio astronomy sky viewing. The site also features _Project Argus_ detections, moonbounce signal detections, and space probe signal detections, providing concrete examples of amateur radio astronomy applications. Publications such as the quarterly newsletter _SearchLites_ and various articles by Dr. SETI (H. Paul Shuch, Ph.D.) are available, alongside information on the Third Penn State SETI Symposium in 2025. The site also offers insights into hydrogen line emission observations, presented in time domain, frequency domain, waterfall, and surface plot formats.
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137 kHz propagation analysis details ground wave and sky wave mechanisms, drawing heavily from **CCIR Rec. 368-6** for ground wave field strength predictions and **CCIR Rep. 265-7** for sky wave modeling. The resource presents field strength values for 1 W ERP at varying distances, considering ground conductivity and permittivity for ground wave, and ionospheric height (70km daytime, 90km nighttime) for sky wave. Key factors like ionospheric focusing (factor "D"), reflection coefficient ("RC"), and antenna ground pattern factors ("Ft", "Fr") are quantified for 137 kHz, enabling calculation of sky wave field strength. Practical coverage ranges are derived for 137 kHz, showing useful ground wave coverage up to 1600 km over seawater and 1100 km over average ground, assuming a -9 dBuV/m noise floor. Sky wave coverage extends beyond 2200 km during night-time and winter daytime, but is negligible during summer daytime at solar minimum. The document also compares ground wave and sky wave strengths, identifying crossover distances at 550 km (night-time), 750 km (winter daytime), and 1250 km (summer daytime), where interference fading can occur. Adjustments for solar maximum conditions are provided, indicating 2-11 dB higher sky wave values depending on distance and season.
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Electroswitch Electronic Products specializes in the design and manufacture of various switch types, including rotary, toggle, pushbutton, and rocker switches, as well as encoders and indicator lights. The company provides commercial and MIL-spec compliant components, detailing features such as spring return, push/pull to turn, adjustable stop, concentric shaft, and keylock configurations for their rotary switch lines. Specific product series like the M5-series enclosed frame rotary switches are highlighted, demonstrating their engineering capabilities. The resource offers a Rotary Switch Configurator to assist customers in selecting appropriate components based on application requirements. It categorizes switches by construction, such as enclosed frame, open frame, military grade, sealed, subminiature, blade, and power options for rotary switches. Toggle switches are presented in miniature, full-size, military grade, and sealed variants, while pushbutton switches include ultra-miniature, miniature, standard, and sealed types. Further product details cover rocker switches in subminiature, miniature, and sealed configurations, alongside thumb switches. Encoder offerings include magnetic and mechanical types with options like concentric shafts and push-to-turn functionality. Indicator lights are available for both commercial rectangular panel mount and MIL-spec applications, featuring configurations such as Press-to-Test, Watertight, EMI Shielded, and Dimmable options.
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This wire antenna for 40 and 20 meter band feature a good SWR. Horizontal side of the antenna is placed at two meters above the ground. Impedance of the antenna are depending by the height of the base from the ground and conditions of the ground
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A considerably shortened Magnetic Loop antenna with performance of a single conductor text book magnetic loop.
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BeaconSpot.uk provides an accurate, real-time picture of microwave and VHF/UHF beacons operating across Europe, alongside a worldwide listing of 6-meter beacons. The platform allows users to retrieve detailed data for individual beacons, facilitating in-depth analysis of signal characteristics and propagation paths. Interactive maps visualize beacon distribution by frequency band and display spot coverage for each station, offering a clear geographical overview of active beacons. The system integrates real-time DXCluster spots, sourced from contributors like Alain, ON4KST, and Pascal, F5LEN, and enables users to submit outgoing spots directly to the DXCluster. Beacon keepers can manage their beacon data, receive email alerts upon being spotted, and track their station's ODX (Outstanding DX) records. For every received spot, the distance to the beacon is automatically calculated and displayed, aiding propagation studies.
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DIXPRS is an APRS Internet Gateway and Digipeater software for HAM radio use. It is designed to be portable and platform independent as much as possible. To reach this goal it is written in Python with minimal dependency considering older versions of operating systems and Python.
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The RSGB Band Plan is normally published annually in the February edition of RadCom and additionally reviewed mid-year. It is derived from the IARU Region 1 Band Plan taking into account any proposed national variations or special amendments, which are considered necessary by the relevant spectrum manager.
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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.
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Announces the retirement of Brand Electronics, a manufacturer specializing in **power meters** and various ham radio accessories, effective 2025. The company has served the amateur radio community for over 35 years, providing equipment for station setup and operation. The product line historically included accessories compatible with major transceivers from Icom, Yaesu, and Kenwood, alongside components and technical references for homebrew projects. Their offerings supported accurate RF power measurement, crucial for optimizing antenna systems and ensuring legal limit compliance. This notice serves as a final update regarding the company's operational status, marking the cessation of manufacturing and sales activities. The site provides no further details on product support or inventory liquidation.
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The article, "Using 75 Ohm CATV Coaxial Cable," details methods for employing readily available 75-ohm CATV hardline in standard 50-ohm amateur radio setups. It addresses the inherent impedance mismatch and practical considerations, such as connector compatibility, for hams seeking cost-effective, low-loss feedline solutions. The resource specifically contrasts common 50-ohm cables like RG-8, RG213, and _LMR-400_ with 75-ohm hardline, highlighting the latter's lower loss characteristics, particularly at VHF and UHF frequencies. It explores two primary approaches to manage the impedance difference: direct connection with an acceptable SWR compromise and precise impedance transformation. The direct connection method acknowledges that a perfect 1:1 SWR is not always critical, especially when using low-loss coax. For impedance transformation, the article explains the use of half-wavelength sections of coax to reflect the antenna's 50-ohm impedance back to the transmitter, noting its single-frequency effectiveness. It also briefly mentions transformer designs using toroid cores and a technique involving two 1/12 wavelength sections of feedline for broader bandwidth. The content further clarifies the concept of _velocity factor_ for calculating electrical versus physical cable lengths, providing a generic formula for precise length determination. It notes that while half-wave matching is practical for 10 meters and above, it can result in excessively long runs for lower bands like 160 meters, potentially adding **250 feet** of cable. The article also mentions achieving a usable bandwidth of 28.000 MHz up to at least **28.8 MHz** on 10 meters with specific transformation techniques.
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A synthesized 2.3 GHz Amateur Television (ATV) transmitter design, conceived by Ian G6TVJ, is presented, targeting broadcast-quality video performance on the 13cm band and extending up to 2.6 GHz. The core of the design utilizes a commercial Z-comm Voltage Controlled Oscillator (VCO) that tunes from 2.2-2.7 GHz, providing a +10 dBm output and simplifying RF alignment. This VCO's stability, originally intended for narrowband applications, readily accepts high-frequency video modulation, contributing to the transmitter's robust performance. The exciter stage, incorporating a Mini Circuits VNA 25 MMIC amplifier, boosts the signal to +16dBm, while a Plessey SP4982 prescaler divides the output frequency for the synthesizer. The synthesizer employs a Motorola MC145151 CMOS parallel IC, favored over the common Plessey SP5060 for its superior video modulation characteristics and ease of programming without microprocessors. This choice addresses issues like LF tilt and distorted field syncs often seen with SP5060 designs, particularly when operating through repeaters or over long distances. The MC145151 divides the signal further, enabling precise frequency stepping, with programming handled by EPROMs for channel selection and LED display. The loop filter network, critical for video integrity, was developed through experimentation to prevent the PLL from reacting to video modulation, ensuring a clean transmitted picture. The transmitter incorporates a Down East Microwave commercial power amplifier module, delivering approximately 1.6W output, driven by the exciter through a 3dB attenuator. Construction involves surface-mount SHF components on micro-strip lines etched onto double-sided fiberglass board, housed within a tinplate box. The design boasts no AC coupling in the video path, preserving low-frequency response, a common failing in other ATV transmitters. Performance tests with a 50Hz square wave revealed no LF distortion, and a calibrated "Pulse & Bar" signal showed a near 100% HF response, demonstrating its capability for high-quality ATV transmissions.
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OZ9FW CDG2000 High-end transceiver homebrew project
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Hjemmeside for amatorradioklubb LA1G, Grenlandgruppen av NRRL
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Having Fun & Fellowship since 1955. The Keystone VHF Club has extensive facilities right outside Rocky Ridge Park just northeast of York, PA.
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The intent of this article is to help the semi-non-technical person understand what is inside the Drake TR-7(A) Transceiver, how it works, and discusses simple adjustment and modifications the end-user can perform
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The Broadcast Employees Amateur Radio Society, Inc. (BEARS) operates an extensive network of **VHF and UHF repeaters** across New York, the Hudson Valley, Long Island, and New Jersey, accessible to all licensed amateur radio operators. This resource details the club's structure as a 501c3 tax-exempt non-profit, emphasizing its role in providing ham radio training, testing, and critical communications support to various public and private emergency response agencies. Key repeaters include W2ABC/RPT on 147.27 MHz with a 141.3 PL tone, serving as a central point for club activities and broader network access. BEARS is also a founding member of the **Disney Amateur Radio Interconnect (DARI)**, a consortium of open, linked VHF and UHF repeaters spanning major metropolitan areas such as Philadelphia, Baltimore/Washington DC, Orlando, Bristol, Los Angeles, and Boston. This interconnected system facilitates wide-area communication for members and supports emergency preparedness efforts across multiple regions. The club's focus extends beyond Disney employees, welcoming aspiring and current hams from outside the company to participate in its activities and utilize its robust repeater infrastructure.
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100-watt UHF repeater (444.500+ PL100) and a 6-meter repeater (53.68- PL114.8) are owned and maintained by South County ARES to support emergency communications for Belmont, East Palo Alto, Foster City, Menlo Park/Atherton, Redwood City, San Carlos, San Mateo, and Woodside/Portola Valley. The organization emphasizes training, including weekly nets and practice sessions, to improve message passing accuracy and brevity, crucial skills for **emergency communication**. Resources like the San Mateo County Sheriff's Office Ham Radio Frequency Plan Recommendation and **Chirp-compatible CSV files** for Baofeng radios are provided. Participation in community events is encouraged to build skills and connections among members. The group operates without collecting dues, relying on donations and member contributions of time and expertise. Training pages are available for new hams and those seeking license upgrades, along with a "Tips for New Hams" section. The site also features a monthly calendar of events, including board meetings, general meetings, and hospital nets, alongside a newsletter, the "South County Communicator," and various operational documents like the Net Control Manual and SCARES Handbook.
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Battery-powered monitor designed to provide an audible indication of keying for those whose rigs lack a CW sidetone
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Evaluates the **LDG Z100 autotuner**, a device designed to automatically match antenna impedance for optimal transmission efficiency. The review discusses its performance in comparison to the MFJ-902, noting that while the Z100 is a reliable autotuner, it does not match the range of impedances that the MFJ-902 can handle. The Z100 is suitable for operators seeking a 100-watt autotuner that covers HF bands, providing a practical solution for those who require automatic tuning without manual adjustments. The review highlights the Z100's operational context, focusing on its use in HF bands and its practical application in amateur radio setups. While it offers a straightforward tuning process, the Z100's limitations in impedance matching are noted, making it less versatile than some competitors. This comparison provides valuable insights for operators considering an upgrade or replacement for their current autotuner. The Z100's performance is positioned within the broader market of autotuners, offering a clear perspective on its strengths and weaknesses in real-world amateur radio operations.
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Demonstrates the complete design and development process for a **Low Noise Microwave Amplifier** (LNA), beginning with conceptual design and progressing through prototyping. The tutorial series covers the initial stages of a single-ended first gain stage, focusing on critical parameters such as noise figure, gain, and stability. It systematically details the theoretical underpinnings and practical considerations for achieving optimal performance in microwave frequency applications. This resource provides a structured approach to LNA construction, enabling radio amateurs and RF engineers to understand the iterative steps involved in realizing high-performance receive-side amplification. It offers insights into component selection, impedance matching networks, and the measurement techniques required to validate design specifications, particularly for **microwave** band operation where noise performance is paramount.
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Inches and meters Javascript Wavelength Calculator allow to input a frequency in MHz and calculate wavelenght in several units considering also fractions of wavelenght and the velocity factor. Includes an usefull inch to meter converter
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First started in the early 80's by a small group of Hams that resided in Cle Elum, Washington.
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K1JJ presents a compilation of insights regarding vertical radial ground systems, specifically applied to 160m vertical arrays. The resource details 19 distinct observations and recommendations, emphasizing that ground radials primarily reduce ground losses rather than influencing pattern formation. It explains that RF current flows inefficiently through average soil, necessitating copper radials to create a low-resistance path back to the antenna base. The content suggests that **50-60 radials** are generally sufficient to achieve optimal efficiency, with diminishing returns beyond that number, and that radials should be laid on the surface for best performance. The discussion also addresses practical aspects such as wire gauge, installation techniques using 'U' shaped staples, and methods for connecting radials in multi-element arrays. It highlights the importance of radial length, stating that 1/4 wave radials are a crucial minimum, and that for 160m, radials should be at least _100 feet_ long. The resource critically examines the efficacy of elevated radials versus ground radials, noting that while a few elevated radials may suffice for VHF, HF applications, particularly on 160m, require extensive ground radial systems to efficiently collect RF currents in the near field. It also touches on the impact of radial systems on parasitic elements and the significance of symmetrical radial patterns for minimizing losses. Further practical advice includes wire type recommendations, proper soldering and weatherproofing techniques for radial connections, and considerations for integrating steel towers into the ground system. The author shares personal experience with installing 60 quarter-wave and half-wave radials under each of three in-line verticals, expressing satisfaction with the results.
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For UK resident amateur radio operators. Sell unwanted Ham gear for free
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Noise Canceller kit originally developed about 1989 by G4WMX and GW3DIX and improved by DK9NL and DG0KW.The VK5TM Noise Canceller is another version of the design, with the HF Vox circuit removed and a couple of other minor changes, including the use of SMD JFETs and a double-sided pcb.
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Twenty-four repeaters, including D-STAR and Fusion systems, are maintained and operated by MARCA Inc., primarily located on Arizona mountaintops and around the Phoenix metropolitan area. The organization, holding the callsign _W7MOT_, facilitates a wide range of amateur radio activities, such as ARRL Field Day events near Forest Lakes, Arizona, and participation in ARRL FMT contests. Members engage in antenna experimentation, construction, and maintenance trips to repeater sites. The club's interests span diverse topics, including HF voice, digital modes like _WSPR_, _WSJT-X_ (FT8, FT4), and CW, alongside DXing, MESH networking, and EOC operations. It supports technologies from SDR radio building to antique radio restoration and computer-based operations like Echolink, fostering a Single Board Computer (SBC) and Raspberry Pi group. Monthly meetings, held on the third Tuesday, feature business discussions and guest presentations, with informal summer gatherings and an annual holiday dinner in December. Monthly VE testing sessions for Technician, General, and Extra Class licenses are conducted by Ray Vasquez, K4RMV. Post-meeting discussions often cover specialized interests such as repeater operations, technical topics, D-STAR, SDR, APRS, Fusion, and Raspberry Pi projects.