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HW VSP is a free software driver that adds a virtual serial port (e.g. COM5) to the operating system and redirects the data from this port via a TCP/IP network to another hardware interface

The RadioFrequency Program is a professional Software dedicated to all HAM, SWL and Radio Listeners. Freeware. Included is a Text-CSV dBase Converter. Connection to the ICOM R8500 Receiver. Special Scanning Feature. Special Search Feature x large dBase.

High wind warning system, programmable, gives progressive series of alarms at three windspeed thresholds. Can be building-mounted or made portable for storm spotters, chasers, etc. Totally unique system!

CW Beacon kit by Expanded Spectrum Systems

HFpack provides an information exchange about transceivers, antennas, systems, HF packs, propagation, new developments and techniques in HF portable operation. Radio Amateurs are invited to participate in egroup and on-the-air nets around the world.

Professional ready-to-use PCB design product.

The 60-page PDF document, "Antenna Systems and Theory For The Non-Technical Ham" by Jim Abercrombie, N4JA, provides a foundational understanding of antenna systems. It explains basic antenna theory, including how antennas work, electromagnetic wave polarization, and the role of frequency. The resource details various antenna types such as flat top dipoles, inverted-V dipoles, shortened loaded dipoles, G5RV dipoles, Carolina Windoms, and end-fed configurations. Vertical antennas, including ground-mounted trapped verticals and inverted-L verticals, are also covered. Directional beam antennas like monoband Yagis, cubical quads, and log-periodic arrays are discussed. Propagation modes, including ground-wave, direct wave, and skywave propagation, are explained in detail, with specific attention to the D, E, and F layers of the ionosphere and their effects on HF communication. Technical concepts such as standing wave ratio, decibels, resistance, and reactance are defined, along with calculations for half-wave resonant dipole lengths. The document addresses feed-line radiation, balun applications, and critical antenna and tower safety considerations. It aims to dispel common antenna myths and educate hams on making informed antenna choices.

The only worldwide amateur radio repeater directory. Supports Android, iPhone, web, RT Systems, CHIRP GPS enabled. AvMap, Garmin, TomTom

Examines JPS Communications' product offerings, focusing on their contributions to Radio over IP (RoIP) and Push-to-Talk over Cellular (PoC) technologies. The resource details how JPS solutions enhance Land Mobile Radio (LMR) capabilities by providing secure and cost-effective methods for communication expansion and interoperability. It highlights the company's 30-year history in developing infrastructure to make communication systems more versatile, secure, and robust, addressing critical needs in various operational environments. The content specifically outlines JPS gateways that bridge traditional radio systems with PoC solutions, facilitating seamless communication across disparate technologies. It also describes multiple approaches for expanding LMR coverage beyond conventional system limitations. The information presented underscores the practical application of these technologies in achieving communications interoperability, irrespective of the underlying systems or protocols, aiming to improve operational efficiency and safety.

All about my hobbies, Ham Radio, Automatic Packet Reporting System and my live streaming web cams and much more!

Optimizing weak signal reception on the HF bands, particularly in the presence of strong local QRM, often necessitates specialized receiving antenna systems. This resource details the _HI-Z Antennas_ product line, focusing on phased vertical arrays designed for superior noise rejection and directivity. It covers components such as the 4-Square and 8-Element array controllers, which allow for rapid switching of receive patterns, and dedicated low-noise preamplifiers to improve system sensitivity. The site also presents various bandpass filters, crucial for mitigating out-of-band interference and enhancing the dynamic range of the receiver. The HI-Z systems are engineered to provide significant front-to-back and side rejection, often yielding **20-30 dB** of attenuation to unwanted signals, which is critical for DXing and contesting. Users can achieve a notable reduction in local noise, allowing for the discernment of signals that would otherwise be buried. The array controllers facilitate quick pattern changes, enabling operators to null out interference or peak weak signals from distant stations, effectively extending the reach of their receive capabilities by improving the signal-to-noise ratio.

Offering transient voltage surge suppressor, TVSS, patch cables, surge arresters, surge protectors for lightning and power surge protection for electrical equipment, IT networks, communication systems, data lines, relay systems and solid state controllers.

This resource provides fundamental guidelines for optimizing mobile amateur radio antenna installations. It addresses critical factors such as achieving an adequate ground plane, minimizing common mode current, and reducing ignition noise. Specific recommendations include mounting antennas on the vehicle's roof for superior radiation patterns and utilizing proper feedline routing to mitigate RF interference within the vehicle's electrical system. The content details the impact of antenna placement on Standing Wave Ratio (SWR) and overall radiated power, emphasizing the importance of a solid electrical connection to the vehicle chassis. It also discusses strategies for noise suppression, such as bonding body panels and employing ferrite chokes on power leads. The information presented is practical for hams seeking to improve their mobile station's efficiency and reduce RF-related operational issues.

Solar panels, solar and wind home power systems, pre-wired power panels. Wholesale prices for everybody. Free solar design.

A 109 pages presentation in PDF File by Jim Brown K9YC on techniques in operatint the top band from a small lot.

Presents the **BayCom** packet radio system, detailing both its hardware and software components specifically designed for amateur radio use. The resource offers insights into the technical specifications and operational aspects of the BayCom modem, which has been a staple for many German packet radio enthusiasts. It covers the integration of these components within a typical amateur radio station setup, enabling reliable digital communication. Further, the site provides a broader context by including general information about the German packet radio network. This encompasses network topology, operational protocols, and historical developments relevant to packet radio in the region. Users can find details on how to connect to and utilize the existing infrastructure, fostering participation in the local digital amateur radio community.

iOS EchoLink client, this free app will allow licenced ham radio operators to use iPhone, iPad or iPod devices to connect to the echoLink system and connect to repeaters or other echolink users.

This document is a must read for anyone considering building a good low cost HF multi-band antenna system. The author combine in this document four important ingredients to produce simple but effective antenna system, like antennas of non resonant length, line attenuation, the transmatch and the balun

Auroral Large Imaging System, ALIS

Presents a construction project for a 1:1 current balun, specifically detailing the _Sorbie Balun and Bottle Choke_ design. The resource outlines the winding technique, employing 4+4 turns of mini coaxial cable on a large ferrite core, and provides insights into the physical assembly. It includes specific material recommendations, such as the type of ferrite and coaxial cable, crucial for achieving the desired impedance transformation and common-mode current suppression. The content covers the practical steps involved in building the balun, from preparing the coaxial cable to securing the windings on the ferrite toroid. It also discusses the integration of the balun into an antenna system, emphasizing its role in maintaining pattern integrity and reducing RF interference in the shack. The resource offers a clear, step-by-step approach, making the project accessible for homebrewers. Illustrations and photographs accompany the text, visually guiding the builder through each stage of construction. The article concludes with performance expectations and considerations for deployment, ensuring the constructed balun functions effectively across the intended frequency range.

This article describe the principles of baluns when referred to devices used to balance unbalanced systems, like a coax cable and a dipole antenna

The A QRP Club is a small group of Amateur Radio enthusiasts who enjoy building, operating and (mostly) talking about Low Power radio communications, equipment and systems.

This page describes how to set up RaspBerry Pi Linux system with already configured AX.25 softwares on SD or micro SD cards

Kenwood TS 990S, Military Auxiliary Radio System modification

The Buddipole Deluxe, a portable HF/VHF antenna system, receives a practical assessment from IW5EDI after a month of field use. The author, constrained by antenna restrictions, highlights the system's crucial role in enabling portable operations, even managing sporadic digital activity from a balcony. Direct comparisons to a fixed 3-band dipole reveal surprisingly comparable signal reports on 15, 17, and 20 meters, underscoring the Buddipole's effectiveness in real-world scenarios. Tuning the Buddipole proves straightforward on bands down to 20 meters, though the review notes significant challenges with SWR on lower bands like 40 meters, where achieving better than 3:1 SWR was problematic. Observations also include SWR variations with dipole rotation and mast height, suggesting environmental factors play a role. The overall manufacturing quality of the antenna and its accessories, including the tripod and carry bag, is deemed good, despite a minor issue with a pole connector. Looking ahead, the author plans to construct a homemade Buddipole version, possibly optimized for the 30-meter band, specifically for PSK31 operations from an apartment. This personal project reflects a common amateur radio practice of adapting commercial designs for specific needs, further extending the utility of portable antenna concepts.

Linux for shortwave and amateur radio monitoring. Supports popular SDR hardware and online streaming from KiwiSDR, WebSDR, and Spyserver sites. Articles about using Linux with your SDR devices.Skywave Linux, an innovative operating system, leverages cutting-edge technology for seamless access to radio signals globally. Ideal for regions with limited internet access, it effortlessly connects to a network of SDR servers, offering high-performance SDR operation without the need for extensive hardware. With pre-installed and configured SDR software, Skywave Linux simplifies signal discovery and operation for all users.

Several bash scripts are provided to automate common amateur radio tasks on Linux and FreeBSD systems, addressing the need for quick access to specific data without navigating web interfaces. These utilities include `call` for fetching US callsign details from callook.info, `qth` for obtaining address information for US and Canadian callsigns, and `grid` for determining grid squares based on license addresses. Each script is designed for command-line execution, allowing for single lookups or interactive sessions, and emphasizes a KISS (Keep It Simple, Stupid) programming philosophy. Another script, `au_kp.sh`, is tailored for weak signal VHF operators, fetching and displaying the NOAA 30-minute Aurora forecast and GFZ Space Weather Kp index data. This script generates static images, requiring re-execution for updates, and is intended to be run as a clickable desktop object for real-time space weather monitoring. It helps operators track propagation conditions, especially during solar cycle peaks. Beyond bash scripts, the resource offers a PHP/web page `fortune` implementation, including Henrik Aasted Sorensen's PHP script, sample HTML/CSS, and a HOWTO guide for creating fortune files. W3DHJ provides several amateur radio-themed fortune files, such as "Ham Humor & Wisdom" with 354 entries and "VHF Rover Humor & Wisdom" with 223 entries, along with other general humor and wisdom collections. These fortune files are designed with embedded HTML for web page display and are refreshed monthly, offering a total of 21,400 entries.

A MacOSX antenna design and electronics/electrical tool package. It is a multipourpose application that allow antenna design and comomn calculations

This graphics-intensive program reveals the load on the output of a matching-network, based on measurements of the components in that network. Adjust the network (tuner) for a flat input, measure or look up the network component values and you will immmediately see the R and jX values of the load on the network, presented as both a schematic with the component values and as a Smith Chart normalized to the specified system impedance.

VHF – Based on realtime APRS reports. This map shows real-time radio propagation from stations operated near 144 MHz. It uses data gathered by Automatic Packet Reporting System-Internet Service (APRS-IS) from packet stations in the amateur radio service. The map shows activity from the past hour. Paths are smoothed to create a color-coded footprint indicating the distance VHF signals are likely to be traveling.

The **TransWorld Antennas TW2010 Traveler HF Portable Vertical Antenna** assembly video provides a visual walkthrough for deploying this popular portable HF antenna. It details the step-by-step process, from unpacking components to final setup, which is crucial for operators preparing for field day operations or DXpeditions. The video focuses on practical aspects, showing how to connect the various elements and secure the antenna for optimal performance. Operators often seek clear assembly instructions for portable antennas like the TW2010 to ensure quick and correct deployment in diverse environments. This visual aid helps clarify potential ambiguities found in written manuals, illustrating the proper handling of the antenna's radial system and telescopic elements. The video serves as a valuable resource for those aiming to achieve efficient operation with the **TW2010 Traveler** in a portable setting. Understanding the assembly sequence can significantly reduce setup time and prevent common errors encountered during initial deployments.

Applied instruments manufactures test and measurement equipment for the broadband telecommunications industry. products include carrier generators, signal level meters, rf switches, spectrum analyzers and a return alignment system.

This article describes an alternative to water as the cooling liquid for amateur radio vacuum tube power amplifiers. This cooling system is designed for adequate vacuum tube cooling, reasonable cost, and very low maintenance. By K8CU

Accessing this interface provides entry to one of the largest databases for amateur radio voice repeaters, encompassing over 8000 entries from more than 60 countries. The resource supports both desktop and mobile access, with a default display based on browser type, or forced via a "force" parameter (e.g., relais.dl3el.de?force=mobile). Users input a QTH-locator to find local repeater information. The database integrates FM-Funknetz servers and hotspots, potentially creating duplicate entries but ensuring new FM-Funknetz repeaters are immediately displayed. DMR repeater information, including status and talkgroup configurations, is sourced directly from DMR+ / ircDDB and Brandmeister systems, with real-time updates for active and default talkgroups. C4FM/Wires-X installations, particularly MMDVM-based gateways not listed in Yaesu's database, are identified through Brandmeister dashboard descriptions, marked with "W-x" or "W-x#MMDVM" for manual entries. D-Star repeater data from ircddb or QuadNet2 is also incorporated, with entries marked (i), (o), or (d) for manual additions. An APRS interface allows searching by callsign, using Sassan, DL3NCK's database, and offers a mobile-friendly, auto-refreshing display that follows an APRS station. Output data can be generated in GPX format for offline smartphone maps or CSV for spreadsheet applications. The database also attempts to determine valid repeater offsets based on IARU region and frequency, indicated by a "." after the frequency.

Understanding the operational impact of Broadband over Power Line (BPL) on amateur radio communications is crucial for any radio amateur, especially given the potential for significant radio frequency interference (RFI). This ARRL tutorial delves into the technical aspects of BPL, explaining how the technology operates by transmitting data over existing electrical power lines, which can inadvertently radiate broadband noise across various amateur bands. My own field experience, particularly on the lower HF bands, has often involved tracking down noise sources that exhibit characteristics consistent with BPL emissions, making this a pertinent topic for maintaining clear receive conditions. The resource further details the specific FCC rules and regulations implemented to restrict BPL deployment. These regulations aim to protect licensed radio services, including amateur radio, from harmful interference. It outlines the technical standards and operational limitations imposed on BPL systems to minimize their impact on the electromagnetic spectrum, a critical aspect for contesters and DXers alike. For those engaged in RFI mitigation, the tutorial provides a foundational understanding of the regulatory framework that can be leveraged when addressing BPL-related interference issues. It serves as a valuable reference for hams seeking to comprehend the technical challenges and regulatory solutions surrounding this pervasive noise source.

Demonstrates the swift setup process for a **Trans World Antenna**, showcasing its utility for portable amateur radio operations. The video highlights the antenna's design for quick deployment, a critical factor for activations like Summits On The Air (SOTA) or Parks On The Air (POTA), where efficiency in establishing a station is paramount. It illustrates the physical components and the sequence of assembly, emphasizing ease of use in varied field environments. The antenna system is presented as a multi-band solution, capable of operating across various HF frequencies. This adaptability makes it a versatile choice for hams engaging in outdoor activities or emergency communications. The visual demonstration provides practical insights into managing the antenna elements and feedline for optimal performance during temporary deployments. The focus remains on the practical aspects of field setup, rather than detailed technical specifications or performance metrics.

This resource, a blog from the Penang Amateur Radio Club (PARC), offers insights into various aspects of amateur radio in Malaysia. One post details monitoring Automatic Terminal Information Service (ATIS) on the 2m band, providing specific frequencies like 122.750 MHz AM for Butterworth and 126.400 MHz AM for Penang, along with sample aviation weather and operational data. Another entry critiques the lengthy and costly process of obtaining an amateur radio license in Malaysia, contrasting it with the more streamlined FCC licensing system in the United States, citing a 1-year wait and RM 414 (USD 125) for 10 years in Malaysia versus 3 weeks and USD 14 for 10 years in the US. The blog also covers internal club matters, such as the 2007 Annual General Meeting (AGM) attendance and council elections, highlighting member dissatisfaction with outdated newsletters and a call for "reformasi." Additionally, it presents local phonetic alphabets in Bahasa Malaysia and Chinese, and discusses monitoring AM broadcast bands for international stations like Voice of America on 1575 kHz and Zhong Yang Ren Min Guang Bo Dian Tai on 1134 kHz, offering alternatives to local 2m repeater chatter. The author, "firstclass," shares personal observations and criticisms regarding the Malaysian ham radio landscape.

A 2 elements delta loop antenna for 14 MHz with a MMana simulation file, dimensions, pictures of this aluminium tube based delta loop antenna, and matching system details.

"Instruments & Systems for Weather & Water Monitoring; weather stations, wind alarms, sensors for wind speed, wind direction, precipitation, temperature, relative humidity, barometric pressure, solar radiation, evaporation, rain & snow gauges, lightning detection."

Marshall G. Emm, N1FN, meticulously examines iambic keying, dissecting its historical introduction in the late 1950s with transistorized electronic keyers and its purported advantages. The resource defines keying systems, electronic keyers, and various paddle types, including single-lever and dual-lever paddles, clarifying the distinction between iambic keyers and the iambic sending technique itself. It details the two main types of squeeze keying: true squeeze for alternating dot-dash strings and character insertion for specific elements within a character. N1FN critically evaluates the actual efficiency gains of iambic keying, referencing Chuck Adams, K7QO's, keystroke analysis. While a straight key to bug transition yields a 34.1% reduction and a bug to non-iambic keyer offers 16.1%, iambic keying provides only an 11% theoretical improvement. However, considering typical QSO text and Morse code's inherent optimization for common letters, the practical efficiency gain is estimated at a modest 4-6%. The article also highlights how iambic keying's reliance on precise timing gates can impose a speed limit, making it less effective above 40 WPM, where many operators revert to non-iambic methods or single-lever paddles.

The _Sci.Electronics FAQ: Repair: RFI/EMI Info_ document, authored by Daniel 9V1ZV, provides a detailed analysis of computer-generated RFI/EMI, focusing on its impact on radio reception. It identifies common RFI sources such as CPU clock rates (e.g., 4.77 MHz to 80 MHz), video card oscillators (e.g., 14.316 MHz), and even keyboard microprocessors, all of which generate square-wave harmonics across HF and L-VHF regions. The resource outlines a systematic procedure for pinpointing RFI origins, including disconnecting peripherals and using a portable AM/SW receiver with a ferrite rod antenna to localize strong interference sources. The document categorizes RFI mitigation into shielding, filtering, and design problems, offering practical solutions for each. It recommends applying conductive sprays like _EMI-LAC_ or _EMV-LACK_ to plastic casings of radios, monitors, and CPUs to create effective Faraday cages, emphasizing proper grounding and avoiding short circuits. For filtering, the guide suggests using line filters, ferrite beads, and toroids on power and data lines, and small value capacitors (e.g., 0.01 uF for serial/parallel, 100 pF for video) to shunt RFI to ground. It also discusses the use of bandpass, high-pass, low-pass, and notch filters on the receiver front-end or antenna feed to combat specific in-band noise.

Gao engineering offers a wide range of affordable, popular and reliable rfid products, dsp, arm and other microprocessor evm and development boards, ides, universal programmers, emulators, dsp learning systems, micro-network terminals, test and measurement products for engineers.

dogparkSDR is a native Macintosh visual radio display and interactive control software for any Flex Radio Systems

PSK Reporter provides a real-time visualization of amateur radio digital mode reception reports, aggregating data from a global network of monitoring stations. This platform is particularly useful for operators utilizing modes such as FT8, FT4, and PSK, allowing them to observe signal propagation paths and assess their station's reach. The interactive maps display reception reports, enabling hams to analyze band conditions and optimize antenna performance for various frequencies and times of day, aiding in understanding ionospheric conditions. Operators can filter reports by callsign, band, mode, and time, gaining insights into specific propagation events or evaluating the effectiveness of their transmit setup. The data collected helps in predicting optimal operating windows for DX contacts across various digital modes. Philip Gladstone is the contact person for comments and discussions regarding the system.

Depiction mapping software can download and integrate maps, elevation plots, weather data, situation reports, damage assessments, volunteer movement, and more. It interface with your APRS ssystem

It is not always possible to tackle the sources of local QRM. What remains is trying to reduce the noise level by means of your antenna system. Learn how to reduce QRM and understand how cancell noises.

PACTOR-II is a fully backward-compatible improvement to the original PACTOR system. It is an adaptive mode that applies different modulation and encoding methods depending on the channel quality.

Operating a ham station often involves encountering radio frequency interference (RFI), RF feedback, or RF burns, which are frequently misattributed to poor equipment grounding. This resource meticulously dissects these assumptions, asserting that RF grounds on the operating desk often merely mask more significant system flaws. It identifies five primary causes for RF problems, including antenna system design flaws, proximity of the antenna to the operating position, DC power supply ground loops, equipment design defects, and poorly installed connectors or defective cables. The content emphasizes that issues like "hot cabinets" or changes in SWR when connecting a ground indicate substantial RF flowing over wiring or cabinets, a phenomenon known as common-mode current. The article provides detailed explanations of common-mode current generation, particularly from single-wire fed antennas like longwires, random wires, and OCF dipoles, which inherently present high levels of RF in the shack. It also illustrates how vertical antennas, lacking a perfect ground system, can excite feed lines with significant common-mode current. Through simulations, the author demonstrates how a dipole without a proper _balun_ can cause RF problems at the operating desk, showing current patterns and voltage distributions on feed line shields. The discussion extends to the proper application of _RF isolators_ and _ferrite beads_, clarifying their role in modifying common-mode impedance on cable shields and cautioning against their use as a band-aid for fundamental system defects. The resource advocates for correcting the actual source of RF problems, such as antenna system issues or poor connector mounting, rather than relying on internal shack grounding or isolators. It highlights that properly functioning two-conductor feed lines, like coaxial or open-wire lines, should result in minimal RF levels at the operating position, even without a desk RF ground. The author shares personal experience, noting that his stations since the late 1970s have operated without RF grounds at the desks, relying instead on proper antenna system design and feed line integrity.

Modification leaves nearly all of the existing Omni agc circuitry intact, simply add an audio detector which modifies the delay characteristics of the original system by G3IXQ

Explains the fundamental principles of Software Defined Radio (SDR) and Digital Signal Processing (DSP) within the amateur radio context, serving as an initial entry point for hams interested in these technologies. It covers the architectural shift from traditional analog hardware to software-centric radio systems, detailing how digital signal processing algorithms are applied to modulate, demodulate, and filter radio signals. The resource compiles a list of external links to _white papers_ and project pages, offering further technical depth. This page provides a foundational understanding of SDR/DSP, enabling operators to grasp concepts like direct sampling and quadrature mixing. It references various projects and discussions, allowing users to explore practical implementations and theoretical underpinnings. The curated links direct users to resources that might cover specific SDR hardware platforms or software applications, facilitating deeper research into the subject.