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Voldatech, a manufacturer based in China, produces a range of RF feeder cables and site components essential for amateur radio installations and telecommunication infrastructure. Their product line includes various types of coaxial cables, such as **50 Ohm** and 75 Ohm options, along with a comprehensive selection of connectors like N-type, UHF, and BNC. These components are critical for maintaining signal integrity and minimizing loss in antenna systems, whether for a home shack or a remote DXpedition setup. The company's focus on _RF Coax cables_ and connectors directly supports the needs of radio amateurs seeking reliable transmission lines for their transceivers and antennas. Amateurs often compare Voldatech's offerings to established brands, evaluating factors such as impedance matching, shielding effectiveness, and durability under various environmental conditions. The availability of diverse cable types allows operators to select optimal solutions for different frequency bands and power levels, from QRP to high-power amplifier setups. Their products are particularly relevant for those constructing new antenna arrays or upgrading existing feedline systems, aiming to achieve maximum power transfer and reduce standing wave ratio (SWR) for efficient signal propagation.

Complete test equipment dealers and distributors directory and test equipment community forum for engineers to share knowledge.

A remote rotor controller, you can use to connect your laptop tablet or smartphone directly to the rotor using it as a Acces point or alternatively it can be connected to existing Wi-Fi network

A list of links to semiconductor manufacturers, including direct links to their datasheets index page

Stand Alone Software Defined Radio, direct sampling receiver from 30 kHz to 1700.00MHz continuous frequency range, LAN interface for remote access

DecoDXLog is a station logbook application for Windows, designed to integrate seamlessly with the _Decodium_ family of software, as well as _WSJT-X_ and JTDX, by receiving QSOs via UDP. It operates around a local SQLite file, providing automatic callbook lookups from QRZ.com XML or HamQTH to complete log entries with name, QTH, and locator data. The software tracks 15 different awards, including DXCC, WAZ, WAS, WPX, IOTA, POTA, and SOTA, calculating progress in real-time and allowing confirmation via LoTW, paper cards, or eQSL. It also features comprehensive statistics, a world map displaying worked locators and cluster spots, and a built-in DX Cluster client that aggregates data from DX Spider/CC Cluster, Reverse Beacon Network, HamAlert, and POTA activations, providing alerts for new DXCC, band, or mode. The application includes a CW keyer/decoder, a contest mode with real-time scoring and Cabrillo export, and robust QSL management for LoTW, QRZ Logbook, eQSL, and Club Log. An optional DecoDXLog Cloud feature enables synchronization of QSOs, station profiles, and settings across multiple devices, ensuring a consistent operating environment. The software is open-source under the GPL-3.0 license, developed by IU8LMC and contributors, and supports lossless ADIF import/export, making it compatible with existing logs. It also integrates with _DecoRotor_ for antenna control, allowing operators to point their antenna directly from the logbook interface.

The RSGB provides a service for its members to exchange QSL cards at a fraction of the cost of sending them direct.

The Bazooka antenna, a coaxial dipole, functions as an omnidirectional antenna with vertical or horizontal polarization. Patented in 1939 and refined in 2006, it features a quarter-wavelength coaxial cable with separated conductors. The outer conductor connects to a sleeve, while the inner conductor extends vertically. Initially complex, it has been simplified for versatile use, including military applications. Adding elements can modify its behavior for NVIS or Yagi-Uda configurations. Experiments in 2007 at the Campus de Pesquisas Geofísicas in Paula Freitas-PR demonstrated consistent VHF and UHF performance, showing reliable return loss measurements despite variable weather.

A W8JK/Moxon antenna variant with 400cm long monopoles is detailed, demonstrating a **1dbd** gain improvement over the traditional Open-Folded W8JK. This design, relying on the _Moxon principle_, achieves higher radiation impedance, leading to increased antenna efficiency and reduced losses. The article includes VNA output data for various HF bands, showing impedance characteristics from 10.1 MHz to 50.1 MHz, and provides NEC model wire definitions for the antenna structure. Field tests performed by F6IIV, Marc, compared his W8JK Moxon style antenna against a Cobweb antenna at the same height. Results indicated the W8JK Moxon variant provided a **6dB** (1 S-meter point) advantage on most bands from 20m to 10m, and a significant 10dB (1.5 S-meter points) advantage on 15m. The antenna features a 2.70m boom and a turning radius of less than 3 meters, making it suitable for limited space installations while maintaining bi-directional performance on most bands.

Although most Preselectors are designed with an internal T/R relay, theoretically enabling direct insertion between the transceiver and the antenna, there is a problem when running CW, especially when running full QSK. The switching time of the internal relay is too slow to follow full QSK. The best way to avoid this problem altogether is to insert the Preselector directly into the transceiver’s RX antenna line, thus avoiding entirely the need to switch the Preselector in and out.

Operating on Airplane scattering. Scattering of radio signals by airplanes. An introduction to operating ariplane scattering, using aircraft to redirect RF that would otherwise be lost in space. Antenna Pointing, Doppler Shift/Digital Modes, using digital modes to operate airscatter.

The build was an experiment to see if a tube receiver could be stable enough to receive digital shortwave radio broadcasts. The tube acts as both an oscillator and mixer, so the receiver is a type of direct conversion receiver.

DXChrono Desktop presents a comprehensive suite of real-time amateur radio data, including NOAA solar indices, HF band conditions, and a worldwide _F5LEN tropo_ overlay for VHF openings. It integrates live spots from Telnet DX Cluster, PSK Reporter, and Reverse Beacon Network, displaying them on a dynamic 3D globe or 2D flat map. Additional features include aurora and MUF layers, QTH display with optional cities and grid/CQ/ITU layers, and dedicated support for SOTA and POTA activations. The software also offers a Watch List for callsign alerts and Sun/Moon Az/El widgets for satellite and EME operations. The application provides extensive contest and logging context through integration with _N1MM Logger+_ UDP, Cloudlog API, QRZ Logbook, and ADIF file support, allowing recent QSOs to be mapped directly. A Special Event mode is available for club stations, enhancing field day operations. DXChrono Desktop runs on Windows, macOS, Linux, and Raspberry Pi 4/5, requiring a 64-bit OS and at least 4 GB RAM for optimal performance, distinguishing it from simpler HamClock-style appliances.

A light portable 2 element Delta beam antenna for 14 MHz. It is basically a two element delta loop wire antenna made for portable usage providing good directivity and a 4.2 dBd gain

A project about reversible unidirectional Beverage antennas plus a remote switching system conveniently controlled by the operator

By CE2NTT; 40-6m; SSB QSL via CE2NTT Direct

Kansas Repeaters directory

A QST Article published in November 1922 is about the origin of Beverage antennas, an unidirectional antenna type that was discovered and experimented for the first time in that period. This article is the introduction to beverage antenna theory, by the homonimous autho H. H. Beverage.

How to connect an Apple MacOS to a USB Radio transceiver. Get a Mac driver for ICOM IC-7100, IC-7200, IC-7300, IC-7600, IC-7610, IC-7850, IC-9100, PCR2500, Kenwood TS-890S, TS-990S, TS-590S, Elecraft KX3, K3S, Yaesu FTdx3000, FT-891, FT-991 or Ten-Tec Eagle USB direct connect built in USB/Serial adapter.

DxDozer is a Windows-based amateur radio logbook designed for both new and experienced DXers, featuring a robust logging system with extensive search capabilities. It offers seamless integration with FT8, displaying received stations from WSJT-X in a DX Cluster-like view, indicating LoTW status and prior contacts, and initiating QSOs directly. The software supports an unlimited number of callsign logbooks and allows multiple operators to log simultaneously to a single database, enhancing its utility for multi-operator stations or contest operations. The application includes a sophisticated DX Cluster with highly configurable filters based on band, mode, continent, worked/confirmed status, and LoTW participation, enabling users to monitor specific calls or countries. DxDozer simplifies QSL management by facilitating one-button uploads to LoTW and ClubLog, and downloads of new confirmed QSOs, with a dedicated field for QSL medium. The software provides both 'Easy' and 'Expert' modes to cater to different user proficiency levels, and is available via a yearly subscription after an initial free trial period.

A hexagonal beam is a form of the Yagi antenna which is based on parasitic principles developed early in the last century in Japan for achieving gain in one direction.How HexBeam antennas works. A hexagonal beam operates exactly like Yagi antenna, but instead of a driven element that is straight like a dipole, it is a wire bent into the shape of the letter M.

This small dual band UHF VHF directional antenna is good choice for portable operations. This antenna is composed by a moxon antenna for the two meters band and it includes two parastatic elements for 70 cm band.

Constructing a directional antenna for VHF operations, particularly for 2-meter band contests or local communication, often involves balancing performance with ease of build. The Moxon rectangle, a compact two-element beam, offers a good front-to-back ratio and gain in a smaller footprint compared to a Yagi, making it suitable for portable or temporary setups where space is limited. This design typically uses a driven element and a single reflector, bent into a rectangular shape to achieve its unique radiation pattern. The article details the construction of a 2-meter Moxon antenna, specifically for 144 MHz, utilizing readily available materials like PVC pipe for the frame and copper wire for the elements. It outlines the dimensions for the driven element at 970mm and the reflector at 910mm, with a spacing of 140mm between them, and a 50mm gap at the element ends. The feedpoint is a direct 50-ohm connection, simplifying matching requirements. The project includes a parts list, a basic diagram illustrating the element layout and dimensions, and photographs of the completed antenna. The author notes the antenna's performance during a QRP contest, achieving contacts up to 100km with 5 watts, demonstrating its effectiveness for low-power VHF work.

The VKFAQ page on Visitors' licences in VK outlines the process for foreign amateur radio operators to obtain reciprocal operating privileges in Australia. It details the varying requirements based on the visitor's home country, ranging from direct use of a home callsign with a VK suffix (e.g., G3PHO/VK1) to needing a full Australian amateur radio license. The resource emphasizes consulting the Australian Communications and Media Authority (ACMA) website for the most current conditions and application procedures, noting that agreements are subject to change. Specific conditions are mentioned for countries with recognized license qualifications, allowing for corresponding Australian licenses. For other countries, a restricted license might be issued, typically permitting 146-148 MHz FM operation with a maximum of 10 watts output. Japanese operators with specific 'telephone or telegraph' licenses may receive privileges for bands above 30 MHz, phone only, also with a 10-watt power limit. Visitor licenses are not automatically renewable but can be extended upon request, provided all conditions are met.

Illustrates the fundamental principles of radio repeaters, detailing their role in extending communication range beyond line-of-sight limitations. It begins by defining _simplex communication_ as a direct radio-to-radio link, effective only when no obstructions impede the signal path. The resource then introduces the concept of a repeater (or base station) strategically positioned on elevated terrain, such as a mountain, to overcome geographical barriers. The article clarifies the repeater's operational mechanism: it receives a signal on one frequency and simultaneously re-transmits it on a different frequency, enabling users on opposite sides of an obstruction to communicate. This _duplex operation_ is likened to satellite communication for VHF propagation, but with a fixed terrestrial station. Specific examples of signal paths are provided, showing how a handheld radio transmits up to the repeater, which then relays the message down to another user, effectively bypassing obstacles like hills or large buildings.

An omnidirectional horizontal polarization antenna for 2 meters band in Italian

Remote Orbitron enables either direct connection between a computer and the shack unit using a serial port OR remote operation from the internet using a WIZ110SR serial to ethernet board.

2 Wavelength ,2 Meter Bi-Square Beam , 5dbd gain. This antennas are very cheeap to build and their radiation pattern is similar to a figure 8 with maximum signal through the loop but they may be used as a near-omnidirectional antenna

Experimental Long Boom Antennas - CP, LPDA, multiband with several NEC Files for 50MHz 144MHz 222 MHz 432MHz but also 902MHz and 1296 MHz Antenna projects. Includes also for each antenna model, in a general comparison table each antenna characteristics including Directive Gain, G/T, E-F/R, H-F/R abd Boom Length. This is a great value comparison table of several commercial and home made VHF UHF antenna projects.

The PCB can produce a High Frequency RF signal in the range of 1MHz to 12.5MHz using an AD9833 Direct Digital Sequence (DDS) frequency synthesizer. The signal can be modulated with different Weak Signal modes such as WSPR, JT9 and JT65 using our Arduino 5V/16MHz Pro Micro software.

An article about the Beverage antennas, super long wire receiving antennas thar are unidirectional and have a very low noise that makes this antenna excellent for low band dxing. By Thomas R. Sundstrom W2XQ, 73, June 1981, 73 Magazine

Receiving **GOES-16** and **GOES-17** weather satellite imagery requires a specific hardware and software configuration, detailed in this practical guide. The author outlines the necessary components, including a Raspberry Pi, an RTL-SDR dongle, a suitable LNA with SAW filter for 1.69 GHz, and a parabolic grid antenna. This setup enables direct reception of high-resolution weather data, a fascinating aspect of amateur radio satellite operations. The installation process begins with preparing the Raspberry Pi, followed by updating the system and installing essential dependencies like `git`, `build-essential`, and `cmake`. A critical step involves compiling and installing `librtlsdr` from source, ensuring proper driver setup and blacklisting conflicting DVB drivers. The guide then walks through testing the RTL-SDR dongle to confirm device recognition and troubleshoot common issues like USB power or driver installation problems. Finally, the instructions cover cloning and building `goestools`, a software suite essential for processing the satellite signals. This compilation, while time-consuming on a Raspberry Pi, is crucial for decoding the raw data into usable imagery. The guide concludes with the initial steps for creating the `goesrecv.conf` configuration file, preparing the system for active satellite reception.

WSJTX-Controller-v2, or Otto, functions as an assistant for the WSJT-X amateur radio program, specifically designed to enhance operational efficiency for weak signal digital modes. The software automates several key tasks, including call management, prioritizing DX stations based on user-defined criteria, and optimizing frequency selection within the WSJT-X interface. It requires a modified version of WSJT-X to function correctly, integrating directly with its core processes to provide augmented control. Otto supports various digital modes, facilitating auto-logging of contacts and generating specific alerts for desired stations or conditions. It is engineered to streamline the workflow for operators engaged in DXing and general weak signal communication, offering features like automatic CQ responses and intelligent band monitoring. The utility is not compatible with certain other amateur radio software and is explicitly noted as unsuitable for contest operations or the WSJT-X Hound mode, indicating its specialized focus on non-contest DX and casual operating. The project's GitHub repository provides the source code and documentation, allowing users to review its implementation and contribute to its development. The software's design emphasizes automation to reduce operator intervention during routine digital mode operations.

The HB9CV antenna calculator aids amateur radio enthusiasts in designing antennas for VHF and UHF bands. By inputting the working frequency, users can obtain crucial dimensions like dipole lengths and distances. The tool, based on the HFSS antenna model, provides data on impedance, VSWR, and gain, optimizing front/back radiation ratios. It includes tips for fine-tuning using a Г-matching balun and compensating capacitor, ensuring effective performance and minimal VSWR for enhanced radio communications and direction finding.

Txtopia provides a browser-based Morse code translator that converts plain text to International Morse Code and decodes Morse back into text, supporting various Unicode dot and dash representations. The tool automatically detects translation direction, normalizes common input variations like middle dots (·), bullets (•), em dashes, and underscores, and explicitly flags unsupported characters or ambiguous sequences with visible placeholders rather than silently dropping them. It accepts spaces, tabs, newlines, and pipes as letter separators, and slashes or blank lines for word boundaries, recording collapsed separators for user review. Users can adjust playback speed from 5 to 40 WPM and tone frequency from 300 to 1000 Hz for CW practice, with playback adhering to international Morse timing. The application operates entirely client-side, ensuring user input remains in the browser without server transmission. It includes a comprehensive reference for the supported Morse alphabet, numbers, and punctuation, aiding in learning and verification. The tool is suitable for checking game clues, verifying tattoo designs, and transcribing messages for ham radio CW practice.

The program serves to assist in a ham-radio activities secretarial with his hobby , such as Printing QSL cards or print labels directly from the program , printing envelopes and mailing envelopes for the feedback you send direct QSL cards, download address for sending cards direct from QRZ.COM or for any station. Checking whether for the QSO and his country is present QSL bureau.

Learn about the practical design and construction of Yagi antennas for ham radio operators. This post explores the benefits of Yagi antennas in receiving and transmitting RF signals, concentrating signal energy in one direction for long-distance communication. Discover the theory behind Yagi antennae, the importance of element size and spacing, and the resources available for sizing and construction. Whether you're interested in OTA television or amateur radio communication, understanding Yagi antenna design can enhance your signal reception and transmission capabilities.

A Lightweight 2m Yagi for SOTA. The boom is 20mm PVC electrical conduit and the elements are 2.4mm aluminium TIG welding rod. The antenna is carried as a single length of conduit with the elements stowed inside the boom, sealing them in with a bung. The driven element is connected directly to 50 Ohm coax with a BN-43-202 balun core to decouple the coax shield.

Presents the construction and performance characteristics of the _Moxon Rectangle_ antenna, a compact, directional HF antenna design. It details the antenna's physical structure, emphasizing its robust build and ease of erection compared to traditional Yagis. The resource provides specific dimensions for building Moxons for the 10m through 40m bands, derived from _W4RNL_'s work, and discusses the critical element spacing for optimal performance. It also covers feeding the antenna with a simple choke balun and achieving a low SWR across the band. Compares the Moxon's performance to a two-element Yagi, noting its superior wind resistance and compact footprint. The author, _VK3BCY_, shares personal experiences with a 20m Moxon, reporting SWRs below 1.3 across the entire band and strong signal reports from DX stations with only 100 Watts. EZNEC Pro modeling data is included to illustrate gain and front-to-back ratios, confirming the antenna's high-performance claims. The article also briefly explores multi-band possibilities and reversible configurations.

The 80-meter Skyloop antenna, a top-performing HF antenna, excels in weak signal work, low-noise operation, and omnidirectional coverage. Ideal for fixed stations, it delivers strong performance at low power, outperforming many alternatives, including 80m half-wave end-fed antennas. Requiring significant space for deployment, it’s well-suited for NVIS and groundwave use. Though not portable, it’s cost-effective and durable, with minor maintenance needs. Tuning may require adjustments for optimal resonance. It’s a standout for base stations, though a lighter portable version could enhance its versatility.

A collection of audio recordings of some DX Peditions used as case studies to evaluate dxspedition operatios behaviour and calling stations. These audio files are excerpts from real pileups recorded directly off the air in MP3 format

This is a simple 2.4 GHz SWR meter which is based around surplus microwave hardware which can be easily found. The main component is a MECA -20/-20 dB Directional Coupler which has a frequency range of approximately 700 MHz to 2.5 GHz.

The Tyler County Amateur Radio Association (TCARA) serves as a focal point for amateur radio operators in Woodville, Texas, and surrounding areas, emphasizing knowledge sharing and skill advancement among its members. The association actively participates in public service communications, including _ARES_, _RACES_, and _Skywarn_ initiatives, demonstrating a commitment to community support through amateur radio. Regular meetings are held on the first Thursday of each month at 6 PM at Calvary Baptist Church, 909 N Magnolia St, Woodville, TX, providing a consistent venue for fellowship and operational planning. TCARA facilitates amateur radio license examinations, offering testing sessions for all license classes, from Technician to Amateur Extra. This commitment to education supports new hams entering the hobby and existing operators upgrading their privileges. Prospective members or individuals interested in licensing, Technician classes, or general club activities are encouraged to reach out via email for further information, indicating a direct channel for engagement.

Details the operational scope and maintenance requirements for the Gloucestershire Repeater Group's amateur radio repeater network. It outlines the financial obligations associated with site rent, electricity, insurance, and professional aerial maintenance, emphasizing the necessity of member support or donations for sustained operation. The resource provides information on accessing individual repeater systems via the site menu. It also announces the 2026 Annual General Meeting (AGM) details, including the date, time, and location at The Robins Nest, Cheltenham Town Football Club, noting the venue is shared with the Cheltenham Amateur Radio Association. The page highlights the availability of the repeaters to all licensed radio amateurs and details how to contribute to their upkeep through membership or direct donations.

Review of the excellent ICOM IC-R8600 Wide Band SDR communications receiver. Featuring Direct Sampling SDR below 30 MHz Hybrid Superhet / SDR above 30 MHz.

The official IOTA web site, designed by the IOTA IT Team to meet the specific needs of those participating in the IOTA programme includes IOTA directory, IOTA spots and all the IOTA programme information.

This utility program shows the impedance and reflection coefficient parameters (SWR, reflection coefficient magnitude Rho, or Return Loss RL in dB) at both ends of a transmission line and the details of power loss in the line. It includes built-in specifications for approximately 100 different line types. You can modify the specs to see how small changes affect the results or to specify custom lines. All program inputs may be changed directly or you can use spin buttons to make the changes.

Otto enhances WSJT-X, the popular weak-signal digital modes program for amateur radio. It automates tasks like managing QSOs, prioritizing DX stations, replying to specific calls, and optimizing band usage. Otto works with a modified WSJT-X version (v2.7.0) to add advanced features such as directed CQs, automatic logging, and multi-stream replies. Its intuitive modes streamline operations, while safety measures ensure controlled transmissions. Ideal for DX enthusiasts, Otto improves efficiency and focus, making weak-signal operations more engaging and productive.

Learn how to build a simple tuned loop antenna for the AM broadcast band to improve the performance of your radio receiver. Discover how to construct a loop antenna with readily available materials, such as balsa and basswood, without the need for specialized woodworking tools. Follow step-by-step instructions to create a portable loop antenna that offers good gain and directivity, ideal for pulling in weak stations. Enhance your Ultralight DX'ing experience and explore the world of FSL antennas through this practical DIY project.

The Beverage we use is a DX Engineering RPS-1 dual directional 360 foot 109,7 m, oriented due North/South, six feet 1,8 m off the ground. The antenna uses 450 ohm ladder line as the antenna, and 75 ohm RG-6u for the feedline. The antenna runs atop the fence between our property and 5 acres of pasture next door.