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Query: HT operation
Links: 1112 | Categories: 11
Categories
- Operating Modes > 70 MHz
- Radio Equipment > HF Amplifiers > Alpha 8410
- DX Resources > DX Peditions
- Operating Modes > JT65
- Radio Equipment > HF Transceivers > Kenwood TS-450S
- DX Resources > Log Analysis
- Radio Equipment > HF Transceivers > Ten-Tec Jupiter
- Radio Equipment > Receivers > Ten-Tec RX-340
- Operating Modes > Top Band
- Antennas > Tuners
- Radio Equipment > HF Transceivers > XIEGU G90
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Coax is a very important part of a satellite station. It is almost as important as the antennas you choose. This article discusses choosing coaxial cables for satellite communication, emphasizing factors like line loss. It compares types such as RG-8, RG-58, Belden 9913/9913F, LMR-400, and hardline, highlighting their impact on signal preservation.
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HFCC manages and co-ordinates global databases of international shortwave broadcasting in keeping with International Radio Regulations of the ITU. Operational Schedule, available for free download and iteractive schedule
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Moon bounce EME, meteor scatter and weak signal operations, introduction by ARRL.
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This page is an introduction to the PocketDigi utility for PocketPC PDAs. Allow PSK, RTTY and CW operation from your PDA by n0hr
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Managing extensive QSO data efficiently requires robust logging software capable of handling diverse operational needs, from casual ragchewing to competitive contesting. HAM OFFICE provides a comprehensive solution for amateur radio operators, integrating essential logging functionalities with advanced features for analysis and award tracking. It supports detailed QSO entry, offers various display and evaluation options, and includes helpful functions to guide users through its interface, ensuring a smooth workflow for both new and experienced hams. The software's design emphasizes user-friendliness while incorporating a wide array of functions, making it suitable for different screen sizes and operating preferences. It features innovative databases for enhanced data protection, improved handling despite increased functionality, and significant speed gains from new background calculations. The program runs stably on Windows XP through 11 (32 and 64 bit) and offers a mobile app for QSO entry and analysis on _tablet PCs_ and smartphones. HAM OFFICE is widely adopted, with an estimated **80%** of German contests logged using the software, and it is utilized by amateurs in **58** DXCC entities. The program supports various aspects of amateur radio, including contest logging, detailed evaluations, and integration with internet resources and shack equipment. It also provides specific support for new license classes like DN9 and actively supports initiatives such as the recognition of _Morse Telegraphy_ as a cultural heritage.
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Operating a ZS6BKW antenna often involves understanding its lineage from the _G5RV_ design, with specific modifications by ZS6BKW to optimize performance on several bands. Through computational analysis and field measurements, the antenna's dimensions were refined to allow operation on 10, 12, 17, 20, and 40 meters without an antenna tuner. For 80, 30, and 15 meters, a tuner is necessary, though efficiency on 30 and 15 meters is noted as not particularly high. The physical configuration consists of two 13.755-meter radiating elements fed by a 12.20-meter section of 450-ohm ladder line. Tuning the antenna on the 20-meter band is critical, and any deviation in the ladder line's characteristic impedance necessitates recalculating the element lengths. The design is also referenced in the 12th edition of _Rothammel's Antennenbuch_, page 219. Proper common mode current suppression is crucial at the transition from ladder line to coaxial cable. This can be achieved with a common mode choke, such as several turns of coax wound into a coil or over a ferrite toroid like an Amidon T130. While a 1:1 balun is an option, it may introduce issues.
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A 90-foot vertical antenna constructed from **aluminum irrigation tubing** is detailed, focusing on its innovative raising and lowering mechanism. The resource describes a **45-foot ginpole** system, allowing a single operator to erect or lower the antenna in minutes. It covers the mechanical design, including the pivot base, insulated joints for the tubing sections, and guy wire attachment points. The antenna consists of two 30-foot sections of 4-inch tubing and one 30-foot section of 2-inch tubing, stacked with the smaller diameter at the top. The electrical design incorporates PVC "condulet" boxes at the 30-foot and 60-foot points, housing relays to change the effective height for multi-band operation on 160, 80, 40, and 30 meters. Ferrite rod inductive chokes are used for DC control and to tune out gap capacitance. The antenna is fed with 1000 feet of open wire line, connected to a matching transformer comprising stacked toroids and a coaxial/toroidal balun. Grounding is achieved with a 3x3 foot grid of 16-gauge tinned copper wires with soldered crossovers.
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A compact multiband wire antenna suitable for portable operations.
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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.
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A magnetic loop made just of wire. Suitable for portable usage and for QRP operations.
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This resource details the conversion of an 80m elevated vertical antenna to include 160m operation, focusing on a relay-switched design over a trap-based approach. It presents specific feedpoint impedance values, such as **32 ohms** for 80m and **14 ohms** for 160m, and discusses the challenges of SWR drift encountered with the prior trap system during RTTY contesting. The article thoroughly explains the design choices for elevated radials, referencing _N6LF QEX data_ to debunk common myths regarding radial length and height, demonstrating that non-resonant radials can offer superior current uniformity. The construction section provides practical insights into building the vertical, including guying strategies, material selection from scrap pipe, and weatherproofing the relay assembly. It highlights the use of a common mode choke for the relay switching line, measuring approximately 5K ohms on both 160m and 80m, and details the L/C matching network's role in achieving a 50-ohm match at the end of a 300-foot RG-11 run. The author describes a precise VNA-based radial trimming procedure, achieving resonant values within a 3 KHz range. The content emphasizes the practical application of theoretical antenna principles, particularly concerning the interaction between the vertical element, cap hats, and the matching network. It offers a candid assessment of component selection, such as using junkbox parts and acknowledging the need for future upgrades to static drain resistors. The article serves as a comprehensive case study for advanced antenna builders tackling multi-band vertical designs.
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Freeware windows program by VE3NEA that allow to view and edit the Master Callsign Database file used in many contesting programs, import and export callsigns, auto-download announced DX operations.
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The IndyScan website functions as a personal blog, documenting the author's experiences across various aspects of daily life, including travel, culinary adventures, and media consumption. Content frequently details personal trips, dining experiences in Indiana and other locations, and reviews of books, television shows, and products. The site also includes reflections on local events and personal purchases, providing a snapshot of the author's interests and activities. While the site's primary focus is personal narrative, it occasionally touches upon amateur radio, such as mentions of operating during a trip to Brookville, Indiana, or capturing a weather fax via shortwave radio. These ham radio-related entries are integrated within broader lifestyle updates, offering a glimpse into the author's engagement with the hobby rather than providing technical guides or detailed operational information. The resource serves as a personal journal, not a dedicated technical reference for amateur radio.
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Deciphering weak or noisy **CW** (Continuous Wave) signals often presents a challenge for amateur radio operators, particularly in contest environments or during DXpeditions. CWLab04X addresses this by providing a software solution that leverages **DSP** (Digital Signal Processing) capabilities of a soundcard to decode Morse code. It functions as both a receiver and a sender, supporting traditional CW and a unique "CCW" mode designed to enhance copyability of signals struggling against high noise floors. The program offers two installation methods: a Windows-specific installer for straightforward setup or a zipped package compatible with Windows and Linux systems running Wine. Users must first download and review the accompanying PDF documentation, CWLab04.pdf and CWLab04_Hardware.pdf, which detail the software's operation and the necessary soundcard interface circuit. The hardware PDF outlines a direct connection from the receiver audio output to the soundcard input, with optional conversion of the soundcard output for hard-keying or microphone input. CWLab04X is intended as an operational aid rather than a replacement for skilled human copy, particularly highlighting the effectiveness of its CCW mode in adverse signal conditions. The software was last revised in April 2009, with installation requiring the LV Runtime 602.
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This vertical antenna consist of a 18 meters telescopic pole and allow operations from 160 to 30 meters band, project by Daniel Zimmerman N3OX
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This webpage describe how to set up the Signalink USB interface and Yaesu FT-857D for digital operations by NA4IT
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All Band HF Doublet for operation over all HF bands including 160m.
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FDLog, a Python-based freeware application, addresses the challenge of synchronized logging for multi-station Field Day operations. It facilitates real-time data sharing across a wireless network, enabling operators to monitor band status and active transmitters at a glance. The software's input system is optimized for minimal keystrokes, streamlining the logging process during intense contest periods. Key features include database synchronization over a wireless network, ensuring all connected computers maintain identical log data. FDLog also incorporates a time synchronization function, designed to keep client programs within a second of a designated master machine, mitigating issues previously encountered with NTP. This internal clock sync can be optionally disabled if not required by the operating setup. Developed initially on Windows 2000, FDLog has demonstrated compatibility with _Linux_ and _macOS_ environments, though some font rendering issues may occur on the latter. The program assists in preparing the ARRL Field Day entry form, simplifying the submission of contest results. User feedback and ARRL rule changes drive ongoing development, with a discussion list available for community support and input.
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One specific challenge in the KazShack, operating Single Operator Two Radios (SO2R), involved sharing a K9AY receive antenna between two transceivers without direct RF connection or manual feedline swapping. The solution, detailed in this project, adapts the **W3LPL RX bandpass filter** design to split 160m and 80m signals, feeding them to separate radio inputs while maintaining isolation. This approach also addresses the issue of strong broadcast band interference from a nearby 50KW WPTF transmitter on 680kc. The construction utilizes T-50-3 toroids and NP0 ceramic capacitors, built in a "dead bug" style on copper clad board. Each band's filter coils are identical and resonated to the desired frequency using an MFJ-259 antenna analyzer. A single DPDT relay, controlled by a remote toggle switch mounted on an aluminum panel, facilitates quick band switching between radios, simplifying low-band operations. While some signal loss is noted, the expected lower noise levels from the receive antenna are anticipated to compensate, potentially reducing the need for constant volume adjustments during toggling between transmit and receive antennas.
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For radio amateurs seeking compact and efficient antenna solutions, particularly for restricted spaces or noise reduction, HF loop antennas present a viable option. This resource compiles several articles from the ARRL, detailing the theory, design considerations, and practical construction of various loop configurations. Topics include small transmitting loops, receiving loops, and multi-band designs, often emphasizing their performance characteristics such as directivity, bandwidth, and impedance matching. The collected articles provide insights into the comparative performance of different loop geometries, such as circular versus square loops, and discuss the impact of conductor size and tuning methods on efficiency. Practical applications are explored, including their use in portable operations, stealth installations, and urban environments where noise mitigation is critical. The content often includes construction diagrams, parts lists, and performance data derived from modeling or field tests, enabling hams to replicate or adapt the designs for their specific operating conditions.
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A simple 40 meter CW transmitter, it sports full break-in operation and 250 mW of output power.
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Presents a construction project for a linear-loaded 40-meter rotatable dipole, detailing the design evolution from mid-element coils to 300-ohm twinlead loading. It covers material selection, including repurposed fishing poles and EMT conduit, and outlines the assembly process for the antenna elements and mounting plate. The resource provides specific measurements for element lengths and linear loading sections, along with SWR plots demonstrating the antenna's resonance at 7.035 MHz with a 1.1:1 SWR, and bandwidth up to 7.120 MHz below 2:1 SWR. The article documents the antenna's performance during various RTTY and CW contests, including the SARTG RTTY and SCC RTTY contests in August 2006, and the ARRL DX CW and CQWW WPX RTTY contests in February 2007. It reports successful operation at 500-1000W, noting improved performance after replacing a faulty coax cable. Specific DX contacts from British Columbia, including stations in Europe and South Africa, are listed, illustrating the antenna's capability despite its shortened length and relatively low height of 55 feet. The content highlights practical considerations such as weatherproofing the connections and supporting the fiberglass elements to prevent sagging. It also includes a brief comparison to an inverted-V at similar height and a ground-mounted vertical, noting the rotatable dipole's quieter reception. The author shares insights into the iterative design process and tuning adjustments made to achieve optimal resonance.
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Over two decades of historical DX spots and news are archived on this Japanese resource, providing a retrospective look at amateur radio propagation and activity across various bands. The content is organized chronologically, with separate sections for _50MHz_, _HF DX_, _144MHz_, _EME_, and Satellite clusters, detailing spot data from as early as 1996 through 2014. This extensive archive serves as a valuable historical record for analyzing long-term propagation trends and significant DXpeditions from a Japanese perspective, offering insights into band openings and rare entity activations. The resource also includes links to other DX news sites like _425 DX News_ and _Ohio/Penn DX Bulletin_, along with QSL manager lookups and callbook services, enhancing its utility as a comprehensive DX information hub. While the primary cluster data is historical, the compilation of external links points to active resources for current DX operations. This makes it a useful reference for contesters and DXers researching past conditions or seeking information on specific DX entities and their QSL routes.
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Examines the historical landscape of "boat anchor" amateur radio equipment manufacturers, focusing on the technical innovations and market dynamics that shaped the industry from the pre-WWII era through the transition to SSB. It details the origins and key product lines of prominent U.S. companies like _Collins Radio Company_, _Central Electronics_, and _Barker & Williamson_, highlighting their contributions to receiver and transmitter design. The resource contrasts early AM technology with the advent of SSB, explaining the circuit changes required in receivers and the complete rethinking needed for transmitters. It discusses the impact of military contracts on company survival and the eventual shift towards smaller, self-contained transceivers. Specific examples, such as the _Collins R-390/URR_ receiver and the _Central Electronics 100V/200V_ broadband transmitters, illustrate the engineering prowess and design philosophies of the era, offering insights into their operational characteristics and enduring appeal among collectors.
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TR4W is a contest logging software package supporting over **180** amateur radio contests. The program operates on Windows 7 to windows 11 operating systems. It supports CW keying via serial port, LPT port, or Winkey, with CW speeds ranging from 1 to **99** WPM. Paddle input via LPT port enables the program to function as a keyer, with paddle input aborting computer-generated CW. PTT support includes programmable delay. The software incorporates automatic super check partial and call checking, along with an expanded .DTA database format for names, QTH, grid, and SS check information. A band map displays color-coded aging data. The software features a built-in telnet DXCluster interface, automatically inserting spots into the band map. It supports RTTY operation via the MMTTY engine and includes WAE QTC support for both European and non-European stations. TR4W provides radio interfacing for Elecraft, Icom, Japan Radio, Kenwood, Ten-Tec, and Yaesu transceivers, utilizing serial or USB-to-serial adapters. Networked multiple-rig operation is supported through a client-server model using TCP/IP protocol. Integrated two-radio support (SO2R) is present. The program includes on-the-fly MP3 recording and log backup to USB drives or selected HDD folders. It uses the standard CTY.DAT file for country and beam heading data.
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R25Log is a DOS-based universal logging program designed for active amateur radio operators, combining standard logging functionalities with several new features. It provides a wealth of information, input, and evaluation possibilities, having been tested and proven in real-world QSO operations. The software supports various operating modes and is specifically tailored for efficient log management. The program's capabilities include comprehensive logging for DXing and contesting, offering detailed input fields and robust evaluation tools. Its _freeware_ status and DOS Shell environment make it accessible for users with legacy systems or those preferring a lightweight logging solution. The design emphasizes practical application, allowing operators to manage their logbooks effectively and analyze their contact data, contributing to improved station performance and award tracking.
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The WT0G crazy W dipole, a solution for 160 meter operations
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The Wireless Institute of Australia (WIA) provides an official directory and database of Australian amateur radio repeaters, detailing their locations, frequencies, and operational status. The resource includes downloadable files in PDF and CSV formats, along with a _Google Earth KMZ_ file for visualizing repeater sites across Australia, including Amateur, CB, and Marine repeaters. It also references external resources for various digital modes such as _IRLP_, _Echolink_, _D-STAR_, P25, Fusion, and DMR, providing links to their respective information sites. The WIA repeater data is cross-referenced with the _ACMA database_ to ensure accuracy, with updates typically occurring twice a year. The directory employs a color-coding system, where purple indicates repeaters carrying the WIA broadcast or callback channels, and a 'W' status denotes operational repeaters with the weekly WIA broadcast. The resource also outlines policies for removing unlicensed or non-operational repeaters from the PDF listing after specific timeframes, while retaining them in the CSV file for potential reinstatement.
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Constructing a portable, high-gain antenna for _AO-40_ satellite operations presents unique challenges, particularly regarding mechanical stability and parabolic accuracy. This resource details the build of a 1.2-meter "brolly dish" antenna, utilizing a non-conducting fiberglass umbrella frame as its foundation. The project outlines a method for achieving a parabolic shape using stressed aluminum fly screen mesh, guided by practical geometry and a temporary dowel template. Key steps include selecting an appropriate umbrella with a suitable f/D ratio (ideally >0.25), removing the original fabric, and precisely cutting and attaching eight segments of fly screen to the struts to form the reflective surface. The construction process, which took approximately five hours for the author, _G6LVB_, resulted in a dish with an f/D of 0.27 (depth=270mm, diameter=1160mm, f=310mm). The article also describes a modification to a _TransSystem AIDC_ feed, incorporating a PCB reflector behind the dipole for easier mounting. Performance tests at a squint angle of 15 deg and a range of 50,000km yielded a signal-to-noise ratio of 33dB on the S2 beacon and 23dB for SSB signals, indicating strong reception. The author notes that the modified umbrella may not close fully without risking surface disfigurement.
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Lowering an NVIS or N.V.I.S. antenna very close to the ground enhances NVIS operation
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Presents the amateur radio activities and interests of Kote, operating as 4L4KW. The page features a collection of external links relevant to the ham radio community, including references to other callsigns such as 4L1BR, 4L1W, 4L4MM, and 4L/ZL1RS, indicating potential connections or shared interests within the Georgian amateur radio scene. It also lists several well-known ham radio resources like QRZ.com, DXzone.com, and Contesting.com, suggesting an active engagement with DXing and contesting. The resource includes links to major amateur radio equipment manufacturers such as Icom, Yaesu, and Kenwood, which implies an interest in modern transceivers and station setup. The mention of DX-Summit and "fixed activity on Ham bands" further reinforces a focus on making contacts and participating in on-air operations. The page serves as a digital hub for 4L4KW's ham radio presence.
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The Maik Uniform France website, established on March 27, 2000, serves as a central hub for French CB radio operators interested in DXing. It provides a platform for sharing DX news, logging contacts, and distributing relevant software tools. The resource caters to various CB DX groups, including Papa Alfa Tango, Wisconsin Michigan, Charly Tango, Oscar Sierra, Big Time Operators, WAC Club, Azteca DX, and TX&RX Group, fostering a community around long-distance CB communications. This online presence facilitates the exchange of operational information and resources among CB enthusiasts. While primarily in French, an English option is available. The site's content structure supports the practical application of CB DXing by centralizing information on recent DX activity and providing utilities, thereby assisting operators in improving their DXing capabilities and staying informed about the CB DX scene.
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PA is a JAVA software package containing several programs, SW/VHF/UHF Logbook (imports format from RADIOMAN, VMT), Log conversion to HTML format, Import and export functions for RADIOMAN, CT RES files, BV QSL Labels, CSV etc. Internet DX-Cluster support, Keeps track of your worked Callsigns, Checks your worked Grid Squares per band, Databases for worked Grids and Callsigns Uses K1EA CQWW.CTY country file, Easy command line version for terminal operation Moontracking as clock, Pathloss calculation
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The DL2NBY Contest Calendar, leveraging the Google Calendar system, presents approximately 400 **HF amateur radio contests**, detailing their dates and rules. It covers a broad spectrum of operating modes, including CW, SSB, and various digital modes like RTTY. The calendar integrates contest information from major organizations such as ARRL and DARC, providing a centralized repository for contest operators. This resource offers the capability to integrate contest events directly into a user's personal Google Calendar, streamlining contest planning. It functions as a comprehensive schedule, allowing operators to review upcoming events and prepare for participation across different bands and modes. The calendar's structure facilitates quick access to contest specifics, aiding in strategic contest operation.
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The San Diego Six SHooters Amateur Radio Club, established in April 2001, is dedicated to promoting all modes of operation on the Six Meter Amateur Radio Band.
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The Pocket Loop is a small magnetic loop antenna designed for a carry anywhere operation, it disassembles in 33 centimeters pieces that can be carried even on an attach handbag.
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A 7MHz Full wave loop antenna in diamond shape for field day operations made with three 31 foot Jackite poles
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Presents the design and performance of a 4-element wire Yagi antenna for the 40-meter band, building upon VE3VN's earlier 3-element switchable wire Yagi. The resource details the antenna's evolution, highlighting the transition from a 3-element to a 4-element configuration and the resulting improvements in gain and front-to-back ratio. It provides specific insights into the antenna's construction and expected operational characteristics. VE3VN shares insights from field results, noting the antenna's performance on 40 meters. The discussion includes the antenna's pattern and matching characteristics, crucial for any DXer or contester looking to optimize their signal on this popular HF band. The author's experience with the previous 3-element design informs the enhancements made to this 4-element iteration. The article includes a visual representation of the antenna's current view, offering a practical perspective on its physical layout. It serves as a valuable reference for hams considering a directional wire antenna for 7 MHz operations, demonstrating a practical approach to achieving enhanced directivity and gain.
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The ZS6BKW antenna, a popular multiband wire antenna, offers improved band matching compared to the traditional G5RV. This construction guide details the process, beginning with specific dimensions: 13.11 meters (43 feet) for the 450-ohm ladder line and initial dipole arm lengths of approximately 14.8 meters each. It emphasizes the critical role of an _antenna analyzer_ for accurate tuning, particularly for determining the velocity factor of the ladder line and achieving a 1:1 impedance match. The article outlines the materials required, including a 1:1 current balun, 450-ohm window line, wire for the dipole arms, and a 50-ohm non-inductive resistor for testing. It provides a step-by-step procedure for cutting the ladder line to its electrical half-wavelength, explaining how to calculate the velocity factor using measured and free-space frequencies. For instance, a measured 50-ohm impedance at 12.54 MHz with a calculated free-space half-wavelength frequency of 11.44 MHz yields a velocity factor of 0.91. Final adjustments involve hoisting the antenna to its operational height and fine-tuning the dipole arm lengths to achieve optimal SWR, specifically targeting 14.200 MHz. The _ZS6BKW_ design is noted for its performance on 80m, 40m, 20m, 10m, and 6m, though it is not optimized for 15m operation. The author, _VK4MDX_, shares practical tips for durable construction using stainless steel wire and cable clamps.
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The 11-meter band, often associated with Citizens Band (CB) radio, presents unique challenges and opportunities for long-distance communication, particularly for operators interested in DXing. This group facilitates discussions and information exchange among enthusiasts who operate on this frequency, often utilizing single-sideband (SSB) modulation for improved range and signal clarity compared to traditional AM CB operations. The community provides a platform for members to share experiences, technical insights, and propagation reports relevant to 27 MHz operations. Members engage in discussions covering various aspects of 11-meter DX, including antenna configurations, transceiver modifications, and operating techniques to maximize signal propagation across continents. The forum serves as a central hub for coordinating contacts, sharing QSL information, and celebrating successful long-haul QSOs. Specific topics often include optimizing power output, reducing noise, and understanding solar cycle effects on 27 MHz. The group's activities extend to organizing virtual gatherings and promoting ethical operating practices within the 11-meter DX community. It supports both seasoned operators and those new to the band, fostering a collaborative environment for exploring the capabilities of CB radio beyond local communications.
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80M field expedient antenna, suitable for NVIS operations
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This resource, "Transistor Audio Preamplifier Circuits," offers comprehensive design guidelines for constructing **bipolar transistor** audio preamplifiers. It delves into critical aspects such as quiescent current setting, voltage gain calculation, and the impact of various component choices on circuit performance. The content provides several _schematic diagrams_ illustrating different preamplifier configurations, including single-stage common emitter and two-stage designs, alongside explanations of their operational characteristics and practical implementation considerations. The analysis extends to frequency response, noise performance, and distortion, providing insights into optimizing these parameters for specific audio applications. The resource presents calculated gain figures for various stages, demonstrating how to achieve desired amplification levels. It also discusses the importance of proper power supply decoupling and input/output impedance matching, crucial for integrating these preamplifiers into larger audio systems or ham radio transceivers. The practical application of these designs is evident in their suitability for microphone preamplifiers or general-purpose audio amplification.
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Whether we are tuning up homebrew equipment, checking antenna VSWR, adjusting a linear amplifier, or just monitoring output power during a contest, almost all aspects of ham operation can use a power meter. Paul Wade W1GHZ
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Demonstrates the design and construction of a compact, portable multi-band mini-delta loop antenna, specifically optimized for /P (portable) operations from remote locations like Scottish islands. The resource covers the theoretical underpinnings of half-wave loops, contrasting closed and open configurations, and then details the application of a folded dipole principle to achieve a 50-ohm match for direct coax feed. It presents empirical formulas for calculating element lengths, considering the velocity factor of common wire types, and provides a detailed example for a 20m (14.175 MHz) version. The article includes a comprehensive table of dimensions and allowances for a five-band (20m, 17m, 15m, 12m, 10m) mini-delta beam, along with construction hints for the central support and balun. It specifies a 1:1 trifilar balun wound on a ferrite rod and describes the antenna adjustment process using an _MFJ-259B Antenna Analyser_. Initial test results indicate an SWR of 1:1 at resonance and a bandwidth of approximately 240 kHz on 20m, even at a low height of five feet above ground. The distinctive utility lies in its focus on a practical, easily deployable beam antenna for portable DXing, offering a viable alternative to more complex or larger arrays.
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The Japanese Amateur Radio Teleprinter Society (JARTS) serves as a central hub for RTTY and PSK31 enthusiasts in Japan, providing essential information regarding its annual JARTS RTTY Contest. The resource outlines contest rules, exchange parameters, and scoring specifics, enabling participants to prepare effectively for the event. It also offers insights into the club's broader activities and its role in promoting digital mode operations within the amateur radio community. The site details the contest's operational periods and categories, which typically include single-operator, multi-operator, and SWL entries, often with power output classifications. Participants can find guidelines for log submission and result publication, ensuring adherence to the contest's administrative requirements. The JARTS RTTY Contest is a significant event for digital mode operators, drawing participation from across Asia and beyond. Beyond contest specifics, the resource provides historical context for JARTS, highlighting its foundational role in Japanese amateur radio digital communications. It serves as a primary point of contact for members and prospective participants, fostering engagement in RTTY and PSK31 modes.
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NetLogger displays 6 currently active nets, including the 3838 Breakfast Club on 80 meters SSB and the CornCobNet on 40 meters SSB, providing real-time updates every 20 seconds to monitoring participants. It functions as a specialized logging program designed for amateur radio nets, facilitating the transmission of check-in data via the internet. The system lists net name, frequency, band, mode, server, start time (UTC), elapsed time, number of subscribers, and the callsign of the operator who opened the net. The platform details specific net operations, such as the Florida AM Group on 3.885 MHz AM and the GRAVEYARD NET on 3.967 MHz SSB, illustrating its application across various **HF** bands and modes. NetLogger's utility extends to viewing past nets and offers a **Groups.io** integration for community interaction. It provides a practical solution for organizing and participating in amateur radio nets, offering a centralized system for tracking participants and net activity. The resource details specific net operations, such as the Florida AM Group on 3.885 MHz AM and the GRAVEYARD NET on 3.967 MHz SSB, illustrating its application across various HF bands and modes.
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The Vee Beam antenna project presents a versatile solution for hams, enabling operation across all eight High Frequency bands (80m to 10m) with significant gain on 20m to 10m. This easy-to-construct antenna utilizes two long wires at an angle, enhancing directional performance and minimizing ground losses. With a low visual profile, it is discreet and effective for various applications. The design allows for optimal leg lengths and included angles, ensuring robust performance while maintaining simplicity in construction and operation. The V Beam antenna is an aerial that you can use on all eight High Frequency amateur bands (80, 40, 30, 20, 17, 15, 12 and 10m) with an antenna tuner, and which gives significant gain on the five bands from 20 to 10 meters band.
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This article presents a technical investigation into spurious emissions from the Yaesu FT-847 transceiver when operating on the 70MHz (4-meter) band. The author discovered significant problems with both factory "UK spec" and modified units. Spectrum analysis revealed that when transmitting at 70.2MHz, the radio produces numerous spurious signals, with the most prominent emission at 45.6MHz measuring only 3dB below the fundamental frequency. The study also documents poor power efficiency on 4m (10.3% at 30W output) compared to 6m operation (23.5% at 30W). Tests verified that jumper configurations had no effect on filter selection. The author warns that using these radios on 4m may violate license conditions due to excessive spurious emissions.
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A 4 yagi beam VHF antenna made with PVC easy to carry in a backpack for portable operations
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Presents a dynamic, searchable database of shortwave broadcast schedules from around the world, enabling users to locate active stations or plan listening sessions based on scheduled transmission periods and frequencies. The resource details specific station names, such as _Radio Habana Cuba_, _Deutsche Welle_, and _All India Radio_, alongside their operational times and assigned kilohertz frequencies. It also incorporates a distance calculator, which leverages geographical coordinates to estimate propagation paths, though it notes occasional data inaccuracies leading to transmitters appearing in oceanic locations. The platform's development log highlights continuous updates, including the integration of new seasonal schedules like "A24 frequencies" and "B23 schedule," reflecting the fluid nature of shortwave broadcasting. It documents challenges with geolocation services, particularly concerning Google API changes that impacted distance calculations and required user-side browser configuration adjustments for optimal functionality. The site owner, VAXXi, frequently communicates these technical adjustments and database updates, often acknowledging user contributions and donations. Distinctively, the resource provides a historical perspective through its update archives, illustrating the evolution of shortwave listening over more than a decade since its inception in 2011. It also mentions specific events, such as the BBC adding shortwave broadcasts for Ukraine on 5875 kHz and 15735 kHz, demonstrating its responsiveness to global events impacting broadcast schedules. The site's commitment to user feedback is evident in its bug reporting and feature request mechanisms, contributing to its ongoing refinement.