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Working with SDR#, adjusting frequency correction and basic setup.
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Win-EQF provides a comprehensive logging solution for amateur radio operators, integrating station control and DX resource management within a single application. It supports various operating modes and offers features for efficient logbook management, essential for contesters and DXers alike. The software is designed to streamline the process of recording contacts and managing station operations, which is crucial for achieving awards like **DXCC** or **WAZ**. Operators can utilize Win-EQF to maintain detailed records of their QSOs, track award progress, and interface with other station hardware. Its robust logging capabilities ensure accurate data capture for every contact, from basic information to specific contest exchanges. The program also facilitates the use of external DX resources, helping operators identify and pursue rare DX entities. This tool is particularly useful for those seeking to optimize their station workflow and enhance their overall operating experience.
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SDR# (read SDR Sharp) is a high performance Software Defined Radio application. SDR sharp is a fully featured SDR capable of handling samplerates from kHz level soundcards up to multi hundred MHz dedicated samplers, thanks to its multi-core architecture.
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The U.S. Amateur Radio Callsign Lookup service, hosted by the University of Arkansas at Little Rock (UALR), offers a direct interface for querying the FCC's amateur radio license database. This resource is specifically designed for rapid retrieval of licensee information, including callsign, name, address, license class, and expiration date, all critical data points for QSLing and contact verification. The underlying database is refreshed daily, ensuring that the presented information reflects the most current FCC licensing records available. This service distinguishes itself by its direct reliance on official FCC data, processed and maintained by a university institution, which lends a degree of authoritative accuracy to its lookups. Users can input a specific callsign to instantly access detailed license particulars, facilitating efficient station identification and record-keeping for DXers and contesters alike. The daily update cycle minimizes discrepancies often found in less frequently synchronized callbook services. The UALR callsign lookup functions as a straightforward, no-frills utility, prioritizing data integrity and accessibility for the amateur radio community. Its operational simplicity and consistent data refresh schedule make it a reliable reference for verifying U.S. amateur radio licenses.
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Demonstrates the essential steps for winding **toroidal cores**, a fundamental skill for amateur radio operators engaged in homebrewing and kit building. It addresses the critical aspects of selecting the correct core material and wire gauge, emphasizing the importance of precise turn counting and consistent winding tension to ensure optimal circuit performance. The resource details methods for preparing the wire, including techniques for safely removing enamel insulation from leads using flame, sandpaper, or a solder pot, and provides guidance on tinning the exposed wire. Explains the process of mounting the wound toroid onto a printed circuit board, highlighting the need for careful lead placement and secure soldering to prevent shorts and ensure mechanical stability. It also offers a practical formula for calculating the required wire length based on the desired number of turns and the specific **toroid** size, referencing common core types like T-50 and FT-240. The guide stresses the importance of verifying the inductance of the wound component, often using an inductance meter, to confirm it matches design specifications. Provides practical tips for handling multi-filar windings and managing short lead lengths, which can be particularly challenging. It underscores the necessity of meticulous attention to detail throughout the winding and installation process to achieve reliable and efficient RF circuits.
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Demonstrates the construction of two distinct wideband RF preamplifiers, detailing their component requirements and performance characteristics. The first design leverages monolithic microwave integrated circuits (MMICs) such as the MAR-6, MAR-8, or PGA103, offering a broad frequency response from DC to 2 GHz with a gain of 22.5 dB at 100 MHz and a noise figure typically below 3 dB. This MMIC-based amplifier incorporates protection against power supply transients and features a 50 Ohm input/output impedance, operating from an 8-20 volt supply with low current drain. The second preamplifier design utilizes a BSX-20 transistor, providing amplification across the 14 MHz to 550 MHz range. This simpler, more economical build achieves an average gain of 12 dB at 145 MHz and a noise figure of approximately 1.1 dB. It operates from a 7-15 volt battery supply with a current draw of 6 mA. Both projects emphasize critical construction techniques, such as maintaining short RF connections, ensuring 50 Ohm impedance paths, and mounting the circuit within a shielded enclosure to optimize performance and minimize noise. The resource also discusses phantom power options for antenna-mounted preamplifiers and precautions for use with transceivers, including output protection diodes and static bleeders.
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Terrasat Communications specializes in advanced RF technology for satellite communication, focusing on _Intelligent Block Up Converters_ (IBUCs) and Solid State Power Amplifiers (SSPAs). These products are engineered to enhance satellite link performance, offering features like extended frequency ranges and high power efficiency. The IBUC series, for instance, integrates a BUC with an SSPA, enabling operators to install, configure, and monitor units for both commercial and military satellite applications, ensuring reliable, high-performance connectivity worldwide. The company's offerings support various satellite bands, including C, X, Ku, and Ka, providing solutions for diverse operational requirements. Their technology is designed for robust field performance, with products like the _IBUC2_ and _IBUCG_ models demonstrating the integration of advanced diagnostics and control capabilities, which are crucial for maintaining optimal signal integrity in demanding environments. Terrasat's focus on _SSPA_ technology underscores a commitment to power efficiency and compact design.
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MorseMaker is an up-to-date replacement for the Morse Machine shown further down this page. It has been re-written using a different programming language and is now entirely 'stand-alone' requiring no run-time support files. This version also works with Windows XP and can use the soundcard but please note that, unlike its predecessor, it does not split the alphabet into smaller 'learning' blocks and does not incorporate the Morse reader.
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Constructing a functional spectrum analyzer for the 0-100 MHz range presents a significant challenge for radio amateurs, often requiring specialized components and careful calibration. This project details a homebrew spectrum analyzer design utilizing common integrated circuits like the _SA605D_ FM receiver IC and _MAR-6_ MMIC amplifiers, aiming for a cost-effective solution. The design incorporates a low-pass filter, RF amplification, a voltage-controlled oscillator (VCO) for downconversion, and multiple IF stages at 150 MHz and 10.7 MHz, with a resolution bandwidth (RBW) of 15 kHz. Critical components such as the _SBL-1_ mixer and varicap diodes are specified, alongside instructions for winding inductors and tuning filters. The analyzer's performance is discussed in terms of input level limitations, specifically the 1dB-compression point and third-order intercept point, to ensure accurate measurements and prevent component damage. The _SA605D_'s logarithmic Received Signal Strength Indicator (RSSI) output serves as the detector, driving the Y-input of an oscilloscope, while a _TL084_ op-amp generates the sweep signal for the X-input. Potential enhancements include adding a step attenuator, improving front-end filtering, and implementing switchable IF filters for variable RBW, allowing for greater versatility in analyzing RF signals.
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Over **10 million** antennas and flags have been sold worldwide by Firestik Antenna Company, a veteran-owned manufacturer specializing in both CB and amateur radio communication products. Their offerings include a range of antennas, mounting accessories, and coaxial cables, designed for various mobile and fixed applications. The company provides technical support and maintains a network of dealers for product availability. Firestik products are known for their fiberglass construction, which is evident in their _Firestik_ and _Firefly_ antenna lines. The company also produces unique items like the "342 mile per hour Firestik flag," highlighting their diverse manufacturing capabilities beyond just radio antennas. They emphasize their commitment to quality and customer service, including direct technical assistance. The company is located in Tempe, Arizona, and operates under the registered trademark of _Pal International Corporation_. They actively protect their brand, including variations like Firestick and Firestix, ensuring proper representation of their products in the market.
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The Deutscher Amateur-Radio-Club (DARC) e.V. serves as the largest association for radio amateurs in Germany and Europe, structured into 24 districts and approximately 960 local chapters nationwide. Its core mission involves fostering amateur radio and establishing favorable conditions for the Amateur Radio Service. The DARC actively participates in international affairs as a member of the **International Amateur Radio Union (IARU)**, ensuring German interests are represented on a global scale. Recent activities include the announcement of the FUNK.TAG in Kassel for April 25, 2026, and the HAMCamp at **HAM RADIO** in Friedrichshafen from June 26-28, 2026, offering discounted participation for young operators up to 27 years old. The club also supports special events, such as a short-term award and special callsign DB15ØWG to commemorate the 150th anniversary of the Weimar–Gera railway line, active from April 1 to June 30. Regular updates, like the Deutschland-Rundspruch 11/2026, cover topics from the status of 70 MHz band permissions to satellite deployments like Ten-Koh 2, and contest results such as the WWA YL event. Propagation forecasts, including Kp indices and solar flux values, are provided by Hartmut Büttig, DL1VDL, offering insights into HF conditions and Gray-Line DX opportunities. The DARC also reports on district elections and space-related events like the Bochumer Weltraumtag, highlighting the diverse engagement of its members.
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The Crossed Field Antenna (CFA) is one of the applications of Correction of Maxwell's Equations which was used over 150 years ago which was proved these days that the Magnetic Field Source is only the Displacement Current not the Conduction Current . These Corrections was made by an Egyptian Doctor Engineer Fathi Kabbary , who reached the New Correct Theory which shows that the height and efficiency of the antenna doesn't depend on the wavelength
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The antenna is an inexpensive, multiband, end fed HF antenna. It has a matching network consisting of a toroid core and an antenna lead of 30
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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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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.
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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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Demonstrates practical solutions for reducing **Radio Frequency Interference (RFI)** in amateur radio operating environments, specifically addressing issues with PC monitors, receivers, and transceivers. The resource compiles advice from experienced operators regarding the selection and application of ferrite cores, including split cores and toroidal cores. It details specific material types like **43, 73, 75, and 77 ferrite**, outlining their effective frequency ranges for RFI suppression, such as 43 material for 30-400 MHz and 77 material for 2-30 MHz. The content provides part numbers for various ferrite products from manufacturers like Fair-Rite Products Corp, distributed by Amidon, and discusses their impedance characteristics across different HF bands. It compares the performance of various ferrite materials at frequencies like 4 MHz, noting that 75 material offers 27 ohms, 73 material 17 ohms, and 43 material just under 10 ohms. Additionally, it touches upon the use of bypass capacitors in conjunction with ferrites to create low-pass filters, emphasizing the importance of identifying common-mode versus differential-mode RFI paths for effective mitigation.
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Presents a detailed construction guide for a **Quadrifilar Helix Antenna** (QHA) optimized for 137 MHz, specifically for receiving weather satellite transmissions. The resource outlines the author's experience building previous QHA designs, highlighting challenges with tuning and nulls, and then focuses on a refined design by John Boyer, documented by Steve Blackmore, which proved easier to build and yielded superior reception. The guide provides precise element dimensions, including 1.5m of 32mm PVC pipe for the mast and 8mm soft copper tubing for the helix elements. It specifies lengths for horizontal tubes (190mm, 90mm) and helix elements (903mm, 1002mm), along with instructions for drilling, assembly, and forming a **balun** by wrapping RG58 coax around the mast. The text emphasizes critical steps like ensuring elements are square and twisting in the correct direction to avoid phase issues. It includes references to original QST articles by Buck Ruperto (W3KH) and the WxSat program for decoding satellite transmissions, contextualizing the antenna's purpose. The article concludes with a sample NOAA 12 image from September 1998, demonstrating the antenna's reception capabilities.
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OM International sideband society incorporated nets 75M, 40M, and 20M Nets begin one hour earlier during Daylight Savings Time
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Have you ever wanted to listen in on a serious SO2R DX contest effort? hear what the low bands sound like from New England? enjoy a contest without having access to a radio? This is your chance!
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The page provides a utility to record QSOs for amateur radio operators, allowing them to send the recorded signal back to the other station. It addresses challenges with VOX capability in radios and offers solutions for different radio models.
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Ferrite Toroids. Iron Powder Toroids. Ferrite Beads. Split Cores. Cable clamp-ons. Balun Cores. W2FMI Baluns and Ununs. Inductive components for EMI Suppression and RFI Suppresion, power supplies, HAM radio.
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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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QRPPAL, developed by WB2QAP, functions as a freeware QRP logging application for Windows 3.1 and Windows 95, initially introduced at the 1996 Dayton Hamvention FDIM QRP symposium. The software integrates the original "Logger" program, which was specifically designed for ARCI contest dupe checking and logging, alongside versions tailored for NW-QRP, MI-QRP Club, and Colorado QRP Club contests. It is distributed as a self-extracting archive, _qrppal!.exe_, approximately 1.2 MB in size, which unpacks _qrppal.exe_ and _setup.exe_ for installation. The program's modular design incorporates extensive QRP-centric databases, covering ARCI awards, QRP club listings, QRP periodicals, kit/vendor directories, and detailed rig reviews, often with photos. Noted reviewer Bob Gobrick, _VO1DRB_, described it as a "QRP Internet Web Site in a box" due to its comprehensive data modules, which are also user-modifiable. Installation involves running _setup.exe_ to create batch files like _setup95.bat_, which then establish a c:\qrppal directory and deploy the program files. Users initiate the application by typing "qrp pal.tkn" after setup. The Colorado QRP Club contest version should be avoided due to specific first name exchange requirements not supported by that module.
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Enables users to convert plain text into _Morse Code_ and, conversely, decode Morse sequences back into readable text. This web-based utility provides a straightforward interface for rapid translation, proving useful for both learning and practical application. It processes input efficiently, displaying the corresponding Morse or text output instantly. Operators can leverage this tool for generating practice copy or for deciphering received CW signals, making it a handy resource for those honing their code skills. The translator handles various character inputs, converting them into standard International Morse Code elements. This simple utility supports quick lookups and real-time conversions, facilitating a better understanding of CW structure and timing. It operates entirely online, requiring no software installation.
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Differential Global Positioning Service (DGPS) is a land-based augmentation system that receives and processes signals from orbiting GPS satellites, calculates corrections from known positions and broadcasts these corrections via a Medium Frequency (MF) Transmitter to DGPS users in the Broadcast Site's coverage area.
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OPCLOG provides a straightforward logging solution for amateur radio operators, enabling the systematic recording of contacts. The software primarily focuses on basic QSO management, allowing users to input essential contact details such as callsign, date, time, frequency, and mode. Its core utility lies in its ability to export log data in the _ADIF_ (Amateur Data Interchange Format) standard, which is crucial for interoperability with other ham radio applications and services. This ADIF export functionality facilitates the creation of personalized QSL cards, streamlining the process for operators who prefer custom designs over generic templates. The program's design emphasizes ease of use for individual station logging, rather than complex contest or DXpedition management. It offers a practical tool for maintaining a personal logbook, supporting the fundamental requirements for tracking contacts and preparing for awards. The software's simplicity ensures a low learning curve, making it accessible for operators focused on routine logging tasks.
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CWRX, a freeware Windows application, decodes Morse code (CW) signals directly from a sound card's audio input, presenting the decoded text on screen. It supports various receive bandwidths and filtering options, allowing operators to optimize signal reception in different QRM conditions. The program's core functionality focuses on robust CW decoding algorithms, crucial for weak signal work and contesting environments. Developed by OZ1IVA, Lars Harbo, this utility provides a straightforward interface for real-time CW interpretation. It integrates basic logging capabilities, enabling users to record decoded transmissions for later review or contest submission. The software is specifically tailored for the Windows operating system, ensuring compatibility with common shack computer setups. Its design emphasizes ease of use for amateur radio operators seeking a dedicated CW decoding solution. The program's small footprint and direct functionality make it a practical tool for both casual listening and more intensive operating sessions, without requiring extensive system resources.
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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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Online calculators for toroid coil, air-core coil inductance, XL, XC, and more.
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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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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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Provides a robust logging solution for amateur radio operators, specifically designed for the Windows operating system. This software streamlines the process of recording contacts, offering built-in _US_ and _Canadian callbooks_ to facilitate rapid lookup and data entry during active operating sessions. The program supports interfacing with external callbook databases such as _Buckmaster Hamcall_ and _RAC CD_, enhancing its utility for DXers and contesters who require quick access to station information. MicroLog is a freeware application, making it accessible for hams seeking a functional logging tool without a financial outlay. Its design focuses on ease of use, ensuring that operators can efficiently manage their log entries and retrieve necessary contact details. The software's continuous development, with updates like the January 8, 2026 version, indicates ongoing maintenance and feature refinement.
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Radio Free Asia (RFA) is a private, non-profit corporation broadcasting news and information in 9 languages to listeners in Asia
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Windows remote control for Yaesu or Icom. Displays the current transceiver settings frequency, mode, and others on the PC in an old-fashioned way that corresponds to the look of receivers in 70's. DX-Cluster Watch (DCW) is an application that automatically refreshes a web page with the dx-cluster content, parses spot lines from it, keeps a consolidated list and inserts the spots to VLR as frequency markers by OK1FIG
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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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GW4ALG's _136 kHz Pages_ document the evolution of vertical antennas for the 2200m band, starting with a prototype mounted on a house wall. This initial design, despite achieving the first **395 km** GM-GW QSO, suffered from significant insulation breakdown, high RF losses due to proximity to the house, and difficult tuning adjustments. The author details the challenges of maintaining resonance and matching with a variometer in the loft, noting that adding three earth spikes offered no measurable improvement over a simple water tap connection. The subsequent experimental 12m vertical, relocated away from the house, significantly reduced dielectric losses and proved far more effective. This antenna enabled GW4ALG to set a world DX record on 136 kHz with a **1916 km** QSO to OH1TN, and an intra-UK record of **703 km** to GM3YXM/P. The resource further explores the use of helium-filled balloons to extend the vertical radiator, achieving heights up to 27m, typically 20m, for enhanced low-band performance. Practical advice on balloon types, inflation, and critical insulation between the wire and balloon is provided, emphasizing safety and avoiding arcing.
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Demonstrates the construction and measurement of a single-turn HF receiving loop antenna, built from common materials like electrical conduit and lamp cord. The resource details the physical dimensions, including a 4-meter circumference, and calculates the theoretical inductance at approximately _6.4 uH_. It outlines a method for determining resonant frequencies across the 4-17 MHz range using a _C Jig_ and a _VR-500 receiver_, coupling the loop with a ferrite ring. The article also discusses the impact of receiver coupling on the loop's Q factor, noting a degradation in sharpness due to the transformer's reflected impedance. Analyzes the observed resonant frequency patterns, highlighting an unexpected rise in the loop's effective inductance at higher frequencies, particularly above 13 MHz. While some increase is attributed to distributed capacitance, the rate of rise suggests further investigation. The experimental setup provides practical insights into the challenges of maintaining high Q in simple receiving loops and offers a comparative reference for other homebrew antenna projects, such as those by _VK2TPM_.
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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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VFO Stabilizer for Kenwood 120, 520, 820, 530, 830 Yaesu FT-101, 901,2 TenTec 580, 540, Triton, Corsair, Omni series, Swan 350, 500cx, Collins KWM 2 and 2A, Drake TR4, T4, R4, Heathkit HW101, SB 104a....and many others
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To save a little time from calculating and experime nting when winding toroid cores here a chart of the most commonly used cores
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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.
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A 500-watt mobile antenna project details the conversion of an old 10m hamstick into a highly efficient, multiband "bugstick" for HF operation. The core modification involves replacing the original coil with 25 turns of 6 turns-per-inch, 1.5-inch diameter coil stock, fabricated from #14 wire. This design, intended for a 3-magnet mount on a vehicle cab, achieves resonance on multiple bands by shorting out specific turns on the coil, similar to a **bugcatcher** antenna. Measurements taken with an MFJ-259 analyzer on a GMC pickup show 0 turns shorted for 20 meters (14.2 MHz), 10 turns for 17 meters, 16 turns for 15 meters, 19 turns for 12 meters, and 23 turns for 10 meters. The construction emphasizes using UV-resistant tie-wraps and #14 solid wire with crimp lugs for robust RF connections, bypassing the fiberglass rod for current flow. A bonus section details a 40-meter version, utilizing 48 turns of 8 TPI, 2-inch diameter coil stock.
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Announce your callsign at least once every ten minutes. HamTime runs in the corner of the screen and gives you an audible alarm when that announcement is due.
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International Components Corporation has an extensive range of electronic components consisting of audible signal devices, speakers, microphones, capacitors, electron tubes, connectors, and accessories designed in recognition of the diversity of applications and special characteristics encountered by designers in today's complex world.