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The IFR-100 PMR446 radio, developed by ICIT Co., Ltd., incorporates a unique _private speaker_ function. This feature enables users to receive communications discreetly, preventing audio from being broadcast aloud from the radio's internal speaker. Instead, the operator can hear transmissions exclusively through a connected earpiece or similar accessory, facilitating private talk mode operations. ICIT Co., Ltd. positions itself as a primary developer and manufacturer of PMR446 equipment within Korea. Their product line emphasizes innovative features designed to enhance user privacy and operational flexibility in short-range, license-free radio communications. The company's focus is on delivering specialized two-way radio solutions. The resource highlights the company's manufacturing capabilities and its commitment to developing distinct functionalities for the PMR446 market. It underscores their role in providing specific communication tools for users requiring secure and private audio reception.

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.

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.

Aggregating real-time contest scores, this online scoreboard serves as a central hub for participants and spectators to monitor live progress during amateur radio competitions. It directly interfaces with widely used contest logging programs, collecting score data as operators make contacts. The platform then processes and displays these scores on dedicated contest pages, offering an immediate overview of standings. Supporting a diverse range of **DX contests**, the system accommodates various operating modes and rulesets. It facilitates score tracking for events like the YB DX RTTY, RSGB Commonwealth (BERU), EA PSK63, and the South America 10 Meter contest, among others. This functionality allows contesters to gauge their performance against competitors instantaneously, fostering dynamic participation. The scoreboard's integration with multiple contest log software applications ensures broad compatibility, making it accessible to a significant portion of the contesting community. It provides a crucial service by centralizing score visibility, enhancing the competitive experience for **amateur radio operators** worldwide.

1:49 UNUN using two stacked FT240-43 cores for end fed halfwave antenna. To match the end fed half wave antenna to the coaxial feeder, it is necessary to have a matching network or transmission line transformer.

A 102-inch vertical whip, commonly a CB antenna, forms the core of this low-profile 10-meter antenna design, optimized for the 28 MHz band. The construction details specify three 8-foot radials made from scrap wire, connected to a common point. This simple yet effective setup is designed for ease of construction and deployment, making it accessible for operators with limited space or materials. The design emphasizes using readily available components, including PVC pipe for the mast and a SO-239 connector for the feedline, ensuring a straightforward build process for a resonant quarter-wave vertical. Field results indicate that this antenna provides good performance for local and DX contacts on 10 meters, despite its compact footprint. The author, N8WRL, shares practical insights into its construction and tuning, highlighting its suitability for temporary or permanent installations where a full-sized antenna might be impractical. Comparisons to more complex designs suggest that this low-profile vertical offers a respectable signal-to-noise ratio and effective radiated power for its size, proving that simple designs can yield satisfying on-air results.

Two different ways to create autotransformer for end fed half wave wire antennas, by using ferrite or air core.

The program can be used to calculate inductors (coils) and their number of turns on ferrite cores, ferrite shells and air coils. These can be used for baluns, Ununs, bandpass filters, low pass filters, resonant circuits, and more. The technical specifications of the cores are already integrated in the program. Application is free and runs on Windows 32 bit versions only. To make it run on Windows 10 64 bit need to be unzipped in a single folder.

SPX Communication Technologies, operating under the TCI International brand, presents a range of radio frequency (RF) solutions primarily for government, defense, and commercial sectors. The offerings include advanced systems for spectrum monitoring, communications intelligence (COMINT), and high-frequency (HF) and medium-frequency (MF) broadcasting and communication antenna systems. Specific product lines encompass _Blackbird_ COMINT systems, _Scout_ spectrum monitoring receivers, and various antenna arrays designed for robust performance in challenging RF environments. The resource details the capabilities of these systems, such as wideband signal detection, direction finding (DF), and signal analysis, crucial for intelligence gathering and regulatory compliance. It also highlights the engineering behind their antenna designs, which are optimized for specific frequency ranges and operational requirements, including high-power broadcast applications and secure military communications. The information presented emphasizes the integration of hardware and software for comprehensive RF situational awareness. The company's focus on empowering partners to "Command the Spectrum" underscores its commitment to delivering critical tools for signal interception, analysis, and management across diverse operational landscapes.

This resource compiles claimed scores, often referred to as "rumor scores," for numerous amateur radio contests, providing a historical snapshot of competitive activity from 1993 through 2007. It lists entries for prominent events such as _CQWW CW_, _ARRL Sweepstakes_, _IOTA Contest_, and various _NAQP_ events, categorized by year and contest. Each entry typically includes the contest name and the month/year of operation, allowing users to quickly navigate to specific contest periods. The site also references the _3830 Web Page_ on Contesting.com as the primary submission portal for these claimed scores. The collection offers a unique perspective on contest participation and performance trends over more than a decade, preceding the widespread adoption of real-time score reporting systems. While not official results, these rumor scores provided early indications of top performers and overall activity levels for a wide array of HF and some VHF contests, including _ARRL 10M_ and _CQWW VHF_. The historical data can be useful for analyzing past contest popularity, identifying consistently strong operators, or simply reminiscing about earlier competitive eras in amateur radio.

The CQ World Wide DX Contest records page details the highest scores achieved in the CQ WW DX Contest across various categories and years. It systematically lists records for both SSB and CW modes, segmenting results by entry class such as Multi-Multi, Multi-Two, Multi-Single High, Multi-Single Low, Single Operator High Power, Single Operator Low Power, Single Operator QRP, Single Operator Assisted High, Single Operator Assisted Low, and Single Operator Assisted QRP. Each record entry specifies the callsign, the operator's callsign in parentheses if different, the year of operation, and the total score achieved. The data is further broken down by individual amateur radio bands, including 160m, 80m, 40m, 20m, 15m, and 10m, allowing for granular analysis of performance within specific frequency segments. The page also includes records for the "ALL" band category, representing cumulative scores across all operational bands. The presented records span from 1948 to 2025, providing a historical perspective on contest performance. This resource also references other CQ contests like CQ WPX, CQ WW RTTY, CQ WPX RTTY, CQ 160, CQ VHF, and WW DIGI, indicating a broader context of contest record keeping. It explicitly states that late logs are not included in the records, ensuring data integrity. The page is maintained by the World Wide Radio Operators Foundation, Inc.

The WB5RVZ Genesis Radio G40 build log documents the construction of a 5W QRP 40m SDR transceiver kit, detailing each phase of assembly from power supply to RF filtering. It provides specific component lists, parts placement diagrams, and testing procedures for stages like the local oscillator, Tayloe detector, and RX op-amps. The resource highlights discrepancies between documentation versions and offers practical advice for builders, including a "virtual build" approach to preemptively address potential ambiguities in component identification and placement. It also addresses a specific "VK6IC Fix" for early board revisions, involving trace cuts and jumper wires for improved performance. The build log presents measured voltages and expected current consumption for various stages, such as the 4.9-5.0 Vdc on the 5V rail and under 100mA for RX current. It outlines critical adjustments like image rejection tuning, a common procedure for direct conversion receivers. The resource also includes practical tips for handling components like the 2N3866 transistor and its heatsink, emphasizing pre-assembly. It details the winding of two 1.45 uH toroidal inductors on T50-6 cores with 17 turns of #20 AWG wire, crucial for the RF path.

Online calculator for Input coil data, LC Resonant Frequency and L match

The normal way to make a good balun is to wind a core with a bifilar winding about 8-10 turns, and then connect the coax to one side and the antenna to the other.

CCAE Software Log provides a dedicated platform for amateur radio operators to manage their QSO records, offering functionalities beyond basic logging. This application supports various operational aspects, including contest participation and general DXing activities, catering to the needs of radio enthusiasts who utilize classic equipment such as Collins radios. The software integrates features for efficient data entry and retrieval, allowing users to maintain a detailed history of their contacts. It is designed to be intuitive for operators focused on collecting and preserving their radio communication logs. The program's development by the European Collins Collector Association (F6HOY) suggests a focus on reliability and specific utility for vintage radio enthusiasts. Its core function is to serve as a robust **logbook software**, facilitating organized record-keeping for ham radio operations.

The **HamRacer** voice keyer, a Windows-based application, is showcased in this video, illustrating its utility for radio amateurs participating in SSB contests. It functions as a synthesized PC-based voice keyer, specifically designed for HF and VHF SSB contest operations, allowing operators to transmit pre-recorded or text-to-speech generated messages during rapid-fire exchanges. The demonstration includes actual recorded QSO examples from a contest, featuring contacts with stations such as SP6OWA, S57O, OK1IEI, 9A1DL, OE1PAB, OK1GTH, and 9A1E. These examples highlight the software's practical application in a live contesting environment, demonstrating how it facilitates contest participation for operators who might otherwise face challenges with traditional voice keying. The resource provides a direct look at the software in action, emphasizing its role in promoting inclusivity within the amateur radio contesting community. It details the use of Windows SAPI for speech synthesis, a core component of HamRacer's functionality.

OpenHamClock is a modern, open-source dashboard for amateur radio operators, designed as a web-based successor to the original HamClock. Deployable locally on a Raspberry Pi or via the cloud, it centralizes essential DX operations into a single, intuitive interface. At its core is an interactive world map that visualizes real-time DX spots, signal paths, satellite tracking, and POTA activators. The software seamlessly integrates critical tools like WSJT-X, DX Cluster, and PSKReporter for monitoring digital traffic. Additionally, it provides vital environmental data, including real-time space weather indices, solar activity, and personalized HF propagation predictions. With customizable themes and a modular architecture, OpenHamClock offers modern operators comprehensive, at-a-glance situational awareness of global radio conditions

Demonstrates the fundamental principles for connecting a personal computer to a ham radio transceiver, specifically for utilizing sound card-based digital mode software like those in the MM Hamsoft suite. It details the basic hardware setup, emphasizing the use of shielded leads and proper audio routing from the radio's output to the sound card's input, and from the sound card's output to the radio's microphone or data input. The resource highlights the critical need for transmit attenuation, suggesting a 100:1 voltage divider to prevent overdriving the transmitter's audio stage, and mentions the optional addition of ferrite beads and decoupling capacitors for RFI mitigation. The guide also points to external resources for more detailed pin-outs and interface schematics, such as a specific QSL.net page, and recommends consulting the help files within MM Hamsoft programs for interfacing specifics. It underscores that while the process is straightforward, understanding the audio level management and proper cabling is key to successful operation. The author, VE5KC, provides practical advice drawn from common issues encountered by operators setting up digital mode stations.

General information page including contest scores, station pictures

The Radio Amateur Megacycle Society

The CQ World Wide DX Contest records document top scores, with the Multi-Multi SSB category showing CN8WW achieving **78,170,508 points** in 2000. These records span from 1948 to 2025, categorizing results by region, operating class (e.g., Single Operator High Power, Low Power, QRP, Assisted), and specific bands like 10M, 15M, 20M, 40M, 80M, and 160M. For instance, EF8R (E77DX) holds the All-Band High Power SSB record with **25,747,775 points** in 2025. Each entry includes the callsign (with operator callsign in parentheses for guest ops), year of operation, and total score. The _CQ WW DX Contest_ also features records for the RTTY and VHF contests, alongside the main SSB and CW categories. QRP records demonstrate significant achievements, such as P40W (W2GD) with 5,097,780 points in the All-Band SSB QRP category in 2000. Multi-Two and Multi-Single categories are also detailed, providing a comprehensive overview of competitive performance.

A great amateur radio shack desk done with a second hand solid core door, measuring 32 inches wide by 80 inches long.

Participating in state QSO parties offers a focused opportunity for amateur radio operators to make contacts within a specific geographic area, often aiming to work all counties or administrative divisions. The Michigan QSO Party (MiQP) serves as an annual event where hams worldwide can connect with stations located in Michigan, contributing to county totals and overall scores. This resource provides the official rules, historical results, and information on planned operations, enabling participants to prepare effectively for the contest. Contesters can access details on scoring, exchange requirements, and various operating categories, ensuring compliance with the _Mad River Radio Club_ (MRRC) sponsored event. The site also offers downloadable Michigan county maps, a crucial tool for those pursuing county hunting awards or planning their operating strategy to maximize **multipliers**. Beyond the contest specifics, the platform facilitates community engagement through a link to the official groups.io mailing list, fostering interaction among participants and organizers. It also directs newcomers to the _ARRL_ for general amateur radio licensing information.

J49I operated from Crete Island (EU-015, KM25PH) during the 2008 _CQ WW DX CW Contest_, focusing on multi-operator category participation. The station's activity centered on maximizing contacts and multiplier acquisition across various HF bands during the competitive event. Operators aimed to achieve a high score by leveraging the island's DXCC entity status. The team, comprising Greek and Italian amateur radio operators, utilized the J49I callsign for this specific contest operation. Their efforts contributed to the overall contest results for the 2008 CW segment, with logs submitted reflecting their performance from the European continent.

The Breeze Shooters is an amateur radio organization based in Western Pennsylvania, established in 1937 by a group of local hams. The club's initial focus was on fostering camaraderie and promoting amateur radio activities among its members. Over the decades, its membership has grown significantly, at one point exceeding 1,800 individuals, making it one of the larger regional ham radio clubs. The organization maintains a casual operational structure, emphasizing member participation in various aspects of the hobby rather than strict formal governance. The club actively supports and organizes events such as the annual Breeze Shooters Hamfest, a significant gathering for the amateur radio community in the region. Members frequently engage in contesting, DXing, and local emergency communications support. The club's history includes a strong tradition of mentoring new hams and providing a platform for experienced operators to share knowledge and resources. Its enduring presence in Western Pennsylvania underscores its role in sustaining local amateur radio interest and activity.

The purpose of this webpage is to document an attempt at this project starting with the 80m core receiver first and also having the parts on hand for then adding the first dual conversion band (40m)

The _Alessandro Volta RTTY Contest_ is an annual digital mode competition focusing on Radioteletype (RTTY) operation, challenging participants to make contacts across various HF bands. This event typically occurs in January, drawing a global field of operators aiming to maximize their QSO count and multiplier accumulation. The contest emphasizes accurate exchange of signal reports and serial numbers, with specific rules governing single operator, multi-operator, and SWL categories. Participants utilize software like _N1MM Logger+_ or _WriteLog_ to manage their logs and generate Cabrillo files for submission. Scoring is based on points per QSO, multiplied by unique DXCC entities and Italian provinces worked on each band. The contest encourages both seasoned RTTY contesters and those new to digital modes to engage in competitive HF activity, promoting skill development in digital communication. Final results and logs are typically published on the contest website, showcasing top performers and providing detailed breakdowns of scores.

The Malaysian Amateur Radio Transmitters' Society (MARTS) serves as the national representative body for amateur radio operators across Malaysia, having been established in 1952. This organization plays a crucial role in advocating for the interests of Malaysian hams, fostering community engagement, and supporting the growth of the amateur radio service within the country. MARTS actively participates in national and international amateur radio affairs, often collaborating with organizations like the _International Amateur Radio Union_ (IARU) to ensure the continued development and recognition of amateur radio. The society's activities encompass a range of services for its members, including the dissemination of information regarding licensing, operating procedures, and technical advancements. MARTS also facilitates various on-air events and provides resources to help members improve their operating skills and expand their knowledge base. The organization's long-standing presence since 1952 underscores its commitment to the amateur radio community in Malaysia. MARTS supports local clubs and individual operators, promoting best practices in radio communication and emergency preparedness.

The Alcorn County ARES group provides crucial **emergency communications** support within Alcorn County, Mississippi, operating under the Amateur Radio Emergency Service framework. This organization mobilizes licensed amateur radio operators to assist public safety agencies during emergencies, natural disasters, and other critical events when conventional communication infrastructure fails or becomes overloaded. Their activities include regular training exercises, participation in local drills, and maintaining readiness to deploy communication assets. Members engage in various aspects of amateur radio, including voice, digital modes, and message handling, ensuring a robust and redundant communication network. The group's focus on preparedness and community service aligns with the core principles of ARES, emphasizing rapid response and effective information relay during crises. They often collaborate with local emergency management agencies, such as the Alcorn County Emergency Management Agency, to integrate amateur radio capabilities into broader disaster response plans. Dustin Brumfield, KD5LAP, serves as the Public Information Officer, facilitating outreach and coordination. The club's operational area is specifically Alcorn County, Mississippi, contributing to local resilience.

The N1HFX thermal cooling fan controller project details a practical circuit designed to manage cooling fan operation based on temperature, a common requirement for high-power amateur radio equipment. This build utilizes a **LM34** temperature sensor, providing a linear voltage output directly proportional to Fahrenheit degrees, simplifying the control logic. The circuit's core functionality involves a comparator that activates the fan when a preset temperature threshold is exceeded, ensuring efficient cooling and reducing unnecessary fan noise. This controller is particularly useful for amplifiers, power supplies, or transceivers that generate significant heat during operation. The design incorporates a _TIP120 Darlington transistor_ to drive the fan, capable of handling up to 5 amps, making it suitable for a range of fan sizes and current requirements. Field results indicate stable temperature regulation, preventing thermal runaway in enclosed environments. Construction involves readily available components, making it an accessible project for hams looking to optimize their station's thermal management.

The Mississippi QSO Party, sponsored by the Mississippi Section of the ARRL, offers a prime opportunity for hams worldwide to make contact with Mississippi stations. This annual event encourages both in-state and out-of-state operators to activate Mississippi counties, promoting activity across the Magnolia State's diverse geographic regions. Participants often operate from various locations, including parks and historical sites, contributing to the unique character of the contacts. Operators typically utilize a mix of HF and VHF bands, employing CW, SSB, and digital modes to maximize their QSO count and multiplier acquisition. The exchange usually involves a signal report and county for Mississippi stations, or state/province/country for others. Results are compiled and published, recognizing top scorers in various categories and encouraging friendly competition among participants. The event serves as a significant annual gathering point for the Mississippi amateur radio community, fostering camaraderie and operational skill development.

KComm, a logging and communication program, was specifically engineered for Elecraft K2, K3, and KX3 transceivers, leveraging the Lazarus cross-platform development tool. It operates natively on Windows XP and can be compiled for Linux, with potential for macOS, prioritizing low resource usage for casual DXers and contest participants. The software integrates with external applications like Fldigi for diverse digital modes and CW Skimmer for advanced Morse decoding, enhancing its functionality beyond basic logging. The design philosophy of KComm emphasizes utilizing the physical radio controls for operational adjustments, rather than replacing the transceiver's front panel. It facilitates keyboard CW operation via the Elecraft serial protocol and capitalizes on the K3 and KX3's built-in decoders for RTTY and PSK31. Additionally, KComm supports PSK31, PSK63, and PSK125 through the AE4JY PSK Core DLL on Windows and integrates with PSKReporter.info for spotting. While not a dedicated contest logging or award tracking program, KComm supports ADIF and Cabrillo export for casual use, allowing logs to be imported into other software. The author, G4ILO, ceased all software development, providing KComm "as is" without further support or updates; however, the source code is available under the GNU GPL for community continuation.

RF amplifier products from NP Technologies, Inc. encompass a wide array of specialized designs, including highly linear Class A broadband amplifiers, crucial for maintaining signal integrity across various frequencies. Their portfolio also features cell band amplifiers, specifically engineered for cellular communication infrastructure, and pulse amplifiers, which are vital in applications requiring high-power, short-duration signal bursts. The company's manufacturing capabilities extend to AM and FM broadcast amplifiers, supporting radio transmission systems, and military VHF amplifiers, designed to meet rigorous defense specifications for robust and reliable communications. NP Technologies, Inc. emphasizes comprehensive development, design, manufacturing, and testing processes for all its RF amplifier offerings. This integrated approach ensures that each product, from initial concept to final deployment, adheres to stringent performance and reliability standards. The company's expertise in these areas allows for the creation of custom solutions tailored to specific client requirements, addressing complex RF challenges in diverse operational environments. Their product range demonstrates a commitment to serving multiple sectors, including commercial broadcasting, telecommunications, and defense. The focus on specialized amplifier types underscores their technical depth in RF engineering.

The Order of Boiled Owls of New York (OBONY) serves as a dedicated hub for amateur radio operators passionate about contesting and DXing. Founded to promote skill development and camaraderie within the competitive ham radio sphere, OBONY members actively participate in major domestic and international contests, striving for top scores and _DXCC_ achievements. The club provides a platform for exchanging operational strategies, technical insights, and logging practices, which are crucial for success in high-stakes events. OBONY's focus extends to fostering a vibrant community where both seasoned contesters and newer operators can learn and grow. They emphasize the importance of ethical operating practices and technical proficiency, contributing to the overall advancement of the amateur radio hobby. Members frequently achieve impressive results, with many logging **thousands of QSOs** during major events and consistently placing well in various categories.

Presents the Carolina DX Association's (CDXA) _Contest Corner_, a dedicated resource for amateur radio contesting activities. It features a curated contest calendar, linking to external resources such as the _WA7BNM Contest Calendar_ and the _ARRL Contest Calendar_, providing a broad overview of upcoming events. The page also details CDXA's internal contest programs, including the "CDXA DX King" and "CDXA DX King Classic" for 2026, with specific links for members to submit their scores. Furthermore, the resource integrates with _3830Scores.com_, encouraging CDXA members to submit their contest results and select the club affiliation for tracking. It provides a direct link to view aggregated scores from participating CDXA members, fostering club competition and recognition. The "CDXA Periodic Table of Contest - 2026" is also mentioned, indicating a structured approach to contest planning for the year.

The Vintage Radio and Phonograph Society (VRPS) is a non-profit historical organization, incorporated in Texas, serving enthusiasts in the Dallas-Fort Worth area and surrounding regions. Its core mission revolves around the **preservation** and **restoration** of antique radios and phonographs, fostering a community for those with a general interest in early wireless technology and vintage audio equipment. The society actively supports the new radio/TV museum in Kilgore, TX, demonstrating its commitment to broader historical preservation efforts. Members engage in activities such as "Show and Tell" days, where they bring items for discussion, and participate in an annual convention. Events like the Spring Auction and the 2026 VRPS Convention, scheduled for October 23-25 at the Grapevine Convention Center, provide opportunities for members to connect, share knowledge, and acquire vintage pieces. The organization also highlights related events, such as the Houston Vintage Radio Association's 2026 convention.

Sponsored by the Oklahoma DX Association

This resource presents a placeholder page for the _Tobacco Valley Amateur Radio Club_ (TVARC), signaling the future establishment of an online presence for this amateur radio organization. The page currently displays a "Coming Soon" message, indicating that the club's official website is in development. It serves as a preliminary marker for the club's digital footprint, suggesting an upcoming platform for members and prospective hams. The current state of the page offers no technical details, operational information, or specific club activities. It functions solely as a temporary landing page, prompting site owners to log in for launch and visitors to check back later. The resource does not provide any data on club repeaters, meeting schedules, or special events, nor does it detail any past achievements like **DX contacts** or **contest scores**.

Constructing an End-Fed Half-Wave (EFHW) antenna offers a practical solution for HF operators seeking a multiband wire antenna without the need for extensive radial systems. This design typically employs a high-impedance transformer at the feed point, matching the antenna's inherent high impedance to a 50-ohm coaxial feedline. The article specifically details a 2012 approach, focusing on a transformer with a 49:1 turns ratio, which is a common configuration for EFHW antennas. The resource outlines the construction of a wire element cut for a half-wavelength on the lowest desired band, with specific coil arrangements enabling operation on harmonically related bands such as 40m, 20m, and 10m. It discusses the physical dimensions and winding details for the matching transformer, often utilizing a ferrite toroid core to achieve the necessary impedance transformation. The content provides insights into the operational principles and practical considerations for deploying such an antenna, including methods for tuning and optimizing performance across multiple amateur radio bands. While acknowledging that the presented information from 2012 may be superseded by newer insights, it serves as a foundational reference for understanding EFHW antenna theory and construction.

Demonstrates MegaPhase's extensive product line of RF and microwave coaxial cable assemblies and components, engineered for demanding applications up to 110 GHz. Key offerings include _Test & Measurement Cables_ with superior phase and amplitude stability, _RF & Microwave Cables_ utilizing _GrooveTube®_ technology for high power systems, and a range of RF components like directional couplers and power dividers. The site details specific cable types such as _Alumibend™_ for space-qualified, ultra-light applications through 90 GHz, and armored cables designed for rigorous environments up to 50 GHz, emphasizing their robust mechanical strength and measurement repeatability. The resource highlights applications across diverse sectors, including space programs like the _Hayabusa_ mission, global security (C5ISR), military airborne systems (MIL-T-81490), telecom, and automated testing. It also provides technical insights through "How To" guides on measuring amplitude/phase stability vs. flexure and proper connector cleaning. The company's commitment to quality is underscored by its rigorous testing protocols and a strong warranty, ensuring reliable operation in critical systems.

The CQ WPX Contest website provides information about the international contest based on working all prefixes, with details on dates, rules, results, log submissions, online certificates, and log checking reports. Users can also access a searchable score database, rules FAQ, and follow updates on the blog and social media. The site is a valuable resource for amateur radio operators participating in the WPX Contest.

Article about isolation transformer construction to perform optimal impedance matching. Winding the FCP isolation transformer, includes interesting table for Winding Turns and Lengths and Core Configurations for T300 T200 T400 toroids

Presents the official results for the _CQ World Wide 160-Meter Contest_, a premier event for Top Band enthusiasts. The resource details final scores for both CW and SSB segments, offering links to comprehensive articles, plaque winner lists, and club score breakdowns. It also includes access to score databases for individual modes and years, along with "Soapbox/QRM Comments" from participants, providing insights into operating conditions and experiences. This archive spans results from 2010 through 2025, with a forward-looking note regarding the 2026 SSB contest date adjustment due to a conflict with the _ARRL DX CW Contest_. The site provides specific links for each year, allowing operators to review detailed outcomes, including top scores, errata, and all-time records, such as the _SX5R_ 2017 SSB performance. The structured presentation facilitates easy navigation through historical contest data.

Low-frequency (LF) radio time signals, operating primarily in the 40–80 kHz range, are broadcast by national physics laboratories for precise clock synchronization. Transmitters like **JJY** (40 kHz, 50 kW; 60 kHz, 50 kW), RTZ (50 kHz, 10 kW ERP), MSF (60 kHz, 15 kW ERP), WWVB (60 kHz, 50 kW ERP), RBU (66.66 kHz, 10 kW), and DCF77 (77.5 kHz, 50 kW) cover vast geographic areas, often several hundred to thousands of kilometers. LF signals offer distinct propagation advantages over higher-band transmissions such as GPS. Their long wavelengths (3–6 km) enable effective diffraction around obstacles like mountains and buildings. The ionosphere and ground act as a waveguide, eliminating the need for line-of-sight and allowing a single powerful station to cover extensive regions. Ground wave propagation minimizes ionospheric variability effects on transmission delay, and signals penetrate most building walls effectively. Robust and low-cost receivers, often priced at 20–30 USD/EUR, are widely used in radio clocks. These receivers typically comprise a tuned ferrite core antenna, a receiver IC (e.g., Atmel T4227, U4223B, MAS1016) for amplification and AM detection, and a microcontroller for decoding the time signal and phase-locking a local clock. Specific components for DCF77, MSF, and WWVB are readily available from vendors like HKW Elektronik and Ultralink.

The Michigan Radio Amateur Youth Network (MRAYN) aims to centralize resources for young operators across Michigan, fostering engagement in amateur radio. This initiative brings together various youth-related clubs and activities, providing a dedicated platform for information exchange and participation. The network supports educational efforts and promotes the hobby among younger generations, ensuring continuity and growth within the amateur radio community. Corey Bulock, KD8BOQ, is listed as a key contact for MRAYN, indicating active leadership in coordinating these youth-centric endeavors. The network's focus includes organizing events and sharing relevant content to keep young hams informed and active. By consolidating information, MRAYN simplifies access to opportunities for youth interested in two-way radio communication, from basic licensing to advanced operating techniques.

This EXCEL Program Worksheet calculates the safe operating conditons for a toroidal transformer operating between 1 and 50 MHz. Manufacturer data for complex permeability, magnetic dimensions, and saturation flux density must be available. Some core types which are commonly used in amateur transmission are included. The program produces limiting winding voltages for linear operation and temperature rise over the range of frequencies and power specified.

A 20-meter window frame stealth antenna, based on a design by _PD7MAA_, utilizes a single 620cm wire loop for discreet installation. The feeding mechanism employs a _4C65_ toroidal core, where the antenna loop functions as a single-turn secondary, and the feedline wraps twice. Tuning is achieved via a 30cm twisted wire stub, allowing for SWR adjustment within the 20m band. This design is specified for QRP operation, with a maximum power limit of **25 Watts** to prevent core saturation or arcing. Wire selection recommendations include thin, insulated copper wire (0.75mm to 1mm) for blending with architectural elements. The guide focuses on practical construction steps for a low-profile 14MHz antenna.

A new ham radio shack desk made of a solid core oak door.

The G5O Contest Group blog documents contest operations and related activities of the Stockport Radio Society. It covers various **HF** and **VHF** contests, providing insights into station setup, antenna configurations, and operational strategies employed during events. The content frequently includes post-contest analyses, discussing scores, propagation conditions, and technical challenges encountered. The blog entries detail specific contest participations, often featuring photographs of the operating environment and equipment used. It serves as a chronicle of the group's contesting history, offering practical examples of multi-operator station management and logistical planning for competitive amateur radio events. The group's focus on both local and international contests is evident through the range of events covered. Regular updates provide a continuous record of the group's engagement in the amateur radio contesting community.

This page provides a detailed guide on the Guanella Current Balun for ham radio operators. The author shares very nice schematics, photos, and explanations on the construction and use of this type of balun. The content explains when a balun is needed and how it can help with common-mode currents in antenna systems. It also discusses the construction process, including winding the balun around a ferrite core. This resource is useful for hams looking to improve their antenna systems and reduce common-mode currents for better performance. This article is in Dutch.