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- Operating Modes > WEFAX
- Manufacturers > Antennas > VHF UHF Microwave > Yagi Antennas
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List of latest published Weather Fax world wide schedule including frequencies and modes.
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The Wireless Institute of Australia (WIA) provides an official directory and database of Australian amateur radio repeaters, detailing their locations, frequencies, and operational status. The resource includes downloadable files in PDF and CSV formats, along with a _Google Earth KMZ_ file for visualizing repeater sites across Australia, including Amateur, CB, and Marine repeaters. It also references external resources for various digital modes such as _IRLP_, _Echolink_, _D-STAR_, P25, Fusion, and DMR, providing links to their respective information sites. The WIA repeater data is cross-referenced with the _ACMA database_ to ensure accuracy, with updates typically occurring twice a year. The directory employs a color-coding system, where purple indicates repeaters carrying the WIA broadcast or callback channels, and a 'W' status denotes operational repeaters with the weekly WIA broadcast. The resource also outlines policies for removing unlicensed or non-operational repeaters from the PDF listing after specific timeframes, while retaining them in the CSV file for potential reinstatement.
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The ZS6BKW antenna, a popular multiband wire antenna, offers improved band matching compared to the traditional G5RV. This construction guide details the process, beginning with specific dimensions: 13.11 meters (43 feet) for the 450-ohm ladder line and initial dipole arm lengths of approximately 14.8 meters each. It emphasizes the critical role of an _antenna analyzer_ for accurate tuning, particularly for determining the velocity factor of the ladder line and achieving a 1:1 impedance match. The article outlines the materials required, including a 1:1 current balun, 450-ohm window line, wire for the dipole arms, and a 50-ohm non-inductive resistor for testing. It provides a step-by-step procedure for cutting the ladder line to its electrical half-wavelength, explaining how to calculate the velocity factor using measured and free-space frequencies. For instance, a measured 50-ohm impedance at 12.54 MHz with a calculated free-space half-wavelength frequency of 11.44 MHz yields a velocity factor of 0.91. Final adjustments involve hoisting the antenna to its operational height and fine-tuning the dipole arm lengths to achieve optimal SWR, specifically targeting 14.200 MHz. The _ZS6BKW_ design is noted for its performance on 80m, 40m, 20m, 10m, and 6m, though it is not optimized for 15m operation. The author, _VK4MDX_, shares practical tips for durable construction using stainless steel wire and cable clamps.
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Website dedicated to Coastal Radio Stations, includes frequency lists for memdium frequencies maritime stations
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The Voice of America (VOA) website serves as a primary digital platform for its international news and information services, broadcasting in 44 languages. The resource presents a wide array of current events, geopolitical analyses, and cultural reports, reflecting a global perspective on news originating from the United States. Content spans various regions, including Africa, Asia, the Middle East, and specific country-focused reports from VOA's language services, such as VOA Uzbek, VOA Kurdish, and VOA Russian. The site features top stories, special reports, and sections like "All About America" and "VOA Explains," providing in-depth context on US-related topics and global issues. The VOA platform offers a continuous stream of updated news articles, covering political developments like government shutdowns, diplomatic relations, and international conflicts, alongside social and economic issues. It also includes sections for "Worth Watching" videos and "From VOA's Language Services," highlighting the breadth of its multimedia output. The content is designed to inform a worldwide audience, often presenting multiple perspectives on complex international events and US foreign policy, making it a significant reference for those monitoring global news and shortwave broadcast content.
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Demonstrates the construction and measurement of a single-turn HF receiving loop antenna, built from common materials like electrical conduit and lamp cord. The resource details the physical dimensions, including a 4-meter circumference, and calculates the theoretical inductance at approximately _6.4 uH_. It outlines a method for determining resonant frequencies across the 4-17 MHz range using a _C Jig_ and a _VR-500 receiver_, coupling the loop with a ferrite ring. The article also discusses the impact of receiver coupling on the loop's Q factor, noting a degradation in sharpness due to the transformer's reflected impedance. Analyzes the observed resonant frequency patterns, highlighting an unexpected rise in the loop's effective inductance at higher frequencies, particularly above 13 MHz. While some increase is attributed to distributed capacitance, the rate of rise suggests further investigation. The experimental setup provides practical insights into the challenges of maintaining high Q in simple receiving loops and offers a comparative reference for other homebrew antenna projects, such as those by _VK2TPM_.
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United States and Canadian call sign/scanner frequency databases, Worldwide airport frequencies, FIPS codes, Mass Media searches for DXing and more!
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Presents a dynamic, searchable database of shortwave broadcast schedules from around the world, enabling users to locate active stations or plan listening sessions based on scheduled transmission periods and frequencies. The resource details specific station names, such as _Radio Habana Cuba_, _Deutsche Welle_, and _All India Radio_, alongside their operational times and assigned kilohertz frequencies. It also incorporates a distance calculator, which leverages geographical coordinates to estimate propagation paths, though it notes occasional data inaccuracies leading to transmitters appearing in oceanic locations. The platform's development log highlights continuous updates, including the integration of new seasonal schedules like "A24 frequencies" and "B23 schedule," reflecting the fluid nature of shortwave broadcasting. It documents challenges with geolocation services, particularly concerning Google API changes that impacted distance calculations and required user-side browser configuration adjustments for optimal functionality. The site owner, VAXXi, frequently communicates these technical adjustments and database updates, often acknowledging user contributions and donations. Distinctively, the resource provides a historical perspective through its update archives, illustrating the evolution of shortwave listening over more than a decade since its inception in 2011. It also mentions specific events, such as the BBC adding shortwave broadcasts for Ukraine on 5875 kHz and 15735 kHz, demonstrating its responsiveness to global events impacting broadcast schedules. The site's commitment to user feedback is evident in its bug reporting and feature request mechanisms, contributing to its ongoing refinement.
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DX Finder presents a real-time DX cluster service tailored for amateur radio operators engaged in DX chasing and contesting. The platform aggregates DX spots, Reverse Beacon Network (RBN) data, and PSK Reporter information, displaying current activity across various amateur bands. It provides a centralized interface for monitoring propagation conditions and identifying rare DX entities, aiding operators in making timely contacts. The service integrates multiple data streams to offer a comprehensive view of global amateur radio activity. Users can access real-time spotting data, which includes callsigns, frequencies, modes, and signal reports, facilitating efficient station operation. The inclusion of RBN and PSK Reporter data enhances situational awareness, allowing operators to assess band openings and signal paths more effectively. DX Finder supports both web and Telnet access, catering to different operational preferences. It also features a dedicated JOTA cluster, specifically designed to support the Jamboree On The Air event.
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F5AD describes the ATV repeaters in the south of France, and methods, frequencies, modulations used in ATV in France and in Europ. (French and English)
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It is a application which can be used for troubleshooting CB radio faults, by giving a graphical display of the normal operating frequencies generated by various parts of the CB radios circuits, it can help you identify if a frequency is incorrect or even missing. Another good use for this software is simulating possible frequency expansions, as it allows you to choose any frequency that the PLL is capable of generating, so you can see what the radio will allow you to get !
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Welcome to scannewbedford.com. This site was built for people who would like to hear a live broadcast of New Bedford Massachusetts public services. There are also a few frequencies from other local towns such as Dartmouth, and Fairhaven being broadcasted on our live audio feed. The web site is free for everyone to use and pass along to another friend. Thank you and enjoy the Scan New Bedford Live Scanner Audio Broadcast of New Bedford`s Police, Fire, and EMS.
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Over 1,000 stations in approximately 60 countries were worked using this modified twin-lead folded dipole, demonstrating its effectiveness with just 4 watts on 20 meters. This design, adapted from an ARRL Handbook concept, eliminates the shorting strap found in traditional folded dipoles, simplifying construction while maintaining performance. It utilizes readily available 300-ohm TV antenna feeder ribbon, making it a cost-effective solution for radio amateurs. The antenna's robust construction allows it to handle up to 100 watts without issues, even without a **balun**. The inclusion of a variable trimmer capacitor at the stub provides flexibility for tuning across different frequencies within a band, a practical feature for operators using transceivers like the Icom 735. Formulas are provided to calculate the precise dimensions for any desired operating frequency, enabling customization for various **HF bands**.
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Frequencies, links for scanners, email lists, online audio and more for Maryland, DC, and parts of Delaware and Virginia
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An engineering oriented organization specializing in the design and manufacture of high performance parabolic antennas, 3dB high power RF couplers, Antenna power splitters, directional RF couplers and more items for RF transmission from HF through Microwave frequencies.
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Grahams Goldcoast Australia Radio Scanner Frequencies
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Scanning information and frequencies by Clay Irving N2VKG
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The main purpose of the county hunter's net is to facilitate the operations of those hams seeking to work all counties in the United State. It is also a useful place for CW emergency communications as there is almost always someone monitoring the frequencies.
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Frequency database for Germany. Emergency services, aircrafts, radio and paging system with over 2000 frequencies from all over Germany.
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This modification will allow the MkIIG to transmit on most of the frequencies that it receives on.
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The Considerate Operator's Guide shows frequencies generally recognized for certain modes or activities (all frequencies are in MHz).
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Detection and recording of Schumann resonances and other electromagnetic phenomena at frequencies below 50 Hz By Hans Michlmayr
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The Resonant Feedline Dipole (RFD) HF antenna design utilizes a single piece of coaxial cable and a stranded wire section, forming a 1/4-wavelength radiator. This configuration, based on a 1997 ARRL Handbook design (page 20.17), functions by RF traveling on the inside of the coax shield and returning on the outside, creating the second half of the dipole. A choke wound into the feedline prevents RF current from flowing back down the feedline. Construction details include using RG-58a/u coax for a 75m version, with a 1/4-wavelength section of stranded wire soldered to the center conductor. The document provides choke dimensions for RG-213, RG-8, and RG-58 coax across 3.5 MHz to 28 MHz, specifying cable length and number of turns. Dipole dimensions are also tabulated for frequencies from 3.6 MHz to 28.4 MHz, listing overall length and individual leg lengths. Field tests included deployment near Bryson City at 5 feet off the ground and as a sloper during WCARS Field Day in Asheville, yielding successful local and regional contacts.
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Description, frequencies and sound samples of most popular amateur radio digital modes by DG8FBV
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Details the Northern Amateur Relay Council of California (NARCC) as the regional coordinating body for amateur radio repeaters operating on the 10-meter band and above. It outlines NARCC's function in managing frequency allocations to minimize interference and ensure efficient spectrum use across Northern California. The resource specifies that NARCC operates in cooperation with the FCC and ARRL, indicating its recognized authority within the amateur radio community. The organization's role centers on repeater coordination, a critical aspect of VHF/UHF operations where multiple stations share limited frequency segments. It highlights the support received from local amateur radio operators, underscoring a community-driven approach to spectrum management. The site serves as a primary reference for hams seeking to establish or operate repeaters within the designated service area. NARCC's activities directly impact the operational landscape for _VHF_ and _UHF_ enthusiasts, providing essential guidelines and coordinated frequencies. This ensures orderly communication and prevents conflicts, particularly in densely populated areas of Northern California.
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In this article, the author discusses the importance of good transformers for Beverages, especially for common-mode isolation. The author recommends #43 ferrite for the transformer, and provides the turns required for different core types. The author also recommends using lower permeability ferrites for better performance at lower frequencies.
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The lists are the most comprehensive compilations of frequencies for the Greater Cleveland area
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One point eight MHz to 30 MHz is the operational bandwidth for this 4:1 Ruthroff voltage balun, designed to interface an unbalanced T-Match network with a balanced antenna system. The project details the construction using a _T200-2_ powdered iron toroid core, tightly wrapped in PVC electrical tape for insulation, and wound with 17 double bifilar turns of 1.25mm enamelled copper wire. This outboard balun offers flexibility, allowing hams to trial various baluns based on antenna system and impedance characteristics, rather than integrating it directly into the tuner. The resource includes a schematic of the balun, a wiring diagram showing winding connections, and a table suggesting alternative toroid cores like the T80-2 or T400-2 with corresponding winding counts. Component sourcing is straightforward, listing items such as the _Amidon_ T-200-2 core, SO-239 connector, and a sealed polycarbonate enclosure from Jaycar. Performance evaluation was conducted using an _AIM 4170C_ antenna analyser, demonstrating efficient 1:4 voltage transformation across the specified HF spectrum. Further efficiency tests involved measuring RF power loss at various frequencies, revealing minimal loss—less than 0.7 dB from 3.6 MHz to 30 MHz, and only 2.0 dB at 1.8 MHz. These measurements, performed under ideal 50-ohm conditions, confirm the balun's effectiveness as a low-loss interface for multi-band antenna systems. The page also links to several other balun and unun projects, including 1:1 current and voltage baluns, and 9:1 voltage ununs, providing a broader context for impedance matching solutions.
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Presents a curated collection of newsletters dedicated to _Earth-Moon-Earth_ (EME) communications, primarily focusing on the 432 MHz band and higher microwave frequencies. The resource details various EME DX experiences and news contributions from operators like K2UYH (W6/PA0ZN), offering insights into successful moonbounce contacts and operational strategies. It serves as an archive of specialized content for those engaged in or interested in extreme weak-signal propagation via the moon. The newsletters provide practical information on achieving EME contacts, often including details on station setups, antenna arrays, and signal reports from challenging DX. For instance, operators might report achieving contacts over **750,000 km** round trip, demonstrating the feasibility of long-distance communication on UHF and microwave bands. The content differentiates itself by concentrating on the unique technical and operational aspects of EME, which contrasts significantly with terrestrial DXing, providing a specialized knowledge base for advanced amateur radio operators.
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Memorandum on the Beverage Wave Antenna for Reception of Frequencies in the 550 - 1500 Kilocycle Band", FCC Report 9.2.1, by Benjamin Wolf and Adolph Andersen
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Presents a QRP AM/CW transmitter project specifically designed for the 10-meter band, utilizing a crystal oscillator and a collector-modulated AM oscillator. The design employs a 2N2219(A) transistor in a Colpitts configuration, generating 100 to 350 mW of RF output power depending on the 9-18 Volt supply voltage and modulation depth. Frequency stability is maintained by a 28 MHz crystal, with fine-tuning possible via a Ct1 trimmer capacitor for approximately 1 kHz adjustment. The resource details the RF oscillator stage, implemented with a 2N2219 NPN transistor, emphasizing frequency stability and low power dissipation. It also covers the amplitude modulation stage, managed by a 2N2905 PNP transistor, which impresses audio information onto the carrier. Selective components (C3, C4, C7, C5) enhance voice frequencies within a +/- 5 kHz bandwidth, and modulation depth is controlled by R2 and R3. The project includes a 3-element L-type narrow bandpass filter (Ct3, L3, C10) to suppress harmonics and ensure a clean output signal. The project provides a complete schematic diagram, a comprehensive parts list including specific capacitor, resistor, and inductor values, and construction notes for the coils (L1, L2, L3). It also offers practical advice on enclosure requirements, suggesting an all-metal case or a PVC box with graphite paint for RF shielding. Operational parameters such as current draw (27mA@9V to 45mA@16V) and input impedance (50 Ohms) are specified, alongside guidance on antenna matching and the importance of a valid amateur radio license for 10-meter band operation.
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This handy and cheap portable dipole can be folded and backpacked, carried in use, and adjusted to a very wide range of frequencies by KV5R
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RadioComm can be used to program your Icom radio's memory, or to create nice radio-frequency spectra or to interface your radio to a huge database of frequencies.
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Diplexer is a passive device, a special filter circuit that seperates 2 different bands, not to be confused with the duplexer that usually separate 2 different frequencies on the same band.
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EchoLink and IRLP Internet Radio Linking Project Node's, Hurricane Watch Audio Feed's and Info, Live Scanner/Other Feed's from the USA, Local Ham Frequencies, Online Receiver's, Shoutcast Live Audio Feed's from the USA, Southern California Frequencies and more
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Operating on the 2200m band (135.7-137.8 kHz) often presents challenges for amateur radio transceivers, which typically exhibit poor receiver performance at these very low frequencies. This project addresses the issue by providing a design for a dedicated 137 kHz antenna preamplifier, specifically tailored to improve signal reception for radios such as the _Yaesu FT-817_. The preamplifier circuit utilizes a low-noise FET input stage, crucial for minimizing self-generated noise and maximizing the signal-to-noise ratio from weak LF signals. The design includes a detailed schematic, component values, and construction notes, enabling homebrewers to build a functional unit. The goal is to achieve significant gain, making the faint signals on 2200m more discernible and improving overall band usability. Key design considerations include impedance matching to typical antenna systems and ensuring stable operation across the narrow LF segment. The circuit aims for a **low noise figure** and sufficient amplification to overcome the inherent limitations of general-purpose HF transceivers when operating below **200 kHz**.
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Operating an 80/40/20M fan dipole for DX is analyzed through EZNEC modeling, focusing on the antenna's performance in a real-world, low-height installation. The resource details the physical construction and SWR measurements of the fan dipole, comparing them against EZNEC simulations. It also incorporates High Frequency Terrain Analysis (HFTA) data to illustrate typical DX elevation angles for various regions from New England, providing a crucial context for evaluating antenna patterns. The analysis presents EZNEC-generated azimuth and elevation patterns for each band (80M, 40M, 20M) at specific frequencies, showing gain figures at different elevation angles relevant to DX propagation. It compares the modeled SWR with measured SWR, attributing discrepancies to coax attenuation. The study concludes with observations on the antenna's azimuth performance (omnidirectional within ±1.5 dB) and its less optimal elevation gain at desired DX angles, highlighting the impact of low antenna height on DX capabilities.
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The webpage provides guidance on working 6 Meter DX, focusing on effective operating habits, preparation, and knowledge of the band. It emphasizes the importance of monitoring, clear frequencies, and using CW for weak signals. It also mentions the significance of knowing countries and individual stations on the air to increase chances of working DX. The page recommends utilizing resources like newsletters and websites to stay updated on 6-meter activity and offers suggestions for improving operating skills.
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Discussion group dedicated to those who enjoy monitoring radio frequencies in the VLF radio spectrum and slightly below the VLF spectrum (3-30 KHz).
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Approximately 1,500 unique DX spots are typically visible on the _ODXC Web Monitor_ at any given time, providing real-time intelligence for amateur radio operators seeking DX contacts. This service aggregates spotting data from the _RW3XA-8 Obninsk DX Cluster_ node, presenting it through a straightforward web interface. Users can monitor current activity across various HF bands, identifying stations calling CQ DX or reporting rare entities. The platform supports both traditional telnet access for those using dedicated cluster clients and a Java-based web interface, catering to different operational preferences. It serves as a practical tool for contesters and DXers to track propagation, identify active stations, and plan their operating strategies. The cluster data includes callsigns, frequencies, modes, and spotter information, crucial for effective DX hunting. Integration with other spotting networks like _RBN_ and _PSK Reporter_ enhances its utility.
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The Yaesu VX-5R, manufactured between 199x and 200x, offers a transmit frequency range covering 50-52 MHz, 144-146 MHz, and 430-440 MHz for European models, with US versions extending to 50-54 MHz, 144-148 MHz, and 430-450 MHz. Its receiver boasts an impressive wideband capability from 0.5 MHz to 999 MHz, with cellular frequencies blocked in some regions. The unit provides up to 5 watts RF output on 6 meters and 2 meters, and 4.5 watts on 70 centimeters, with selectable lower power settings down to 300 mW. This handheld transceiver utilizes a double conversion superheterodyne receiver system, featuring a 47.25 MHz first IF for FM and 45.8 MHz for WFM. Key specifications include a frequency stability of ±5 ppm across a wide temperature range and a current drain of 25-150 mA on receive. The VX-5R supports 220 regular memory channels with alpha tags, 3 home channels, and 10 NOAA weather channels, all stored in non-volatile EEPROM. Additional features include CTCSS/PL and DCS with tone search, ARS, ARTS, an internal voltmeter, and a Spectra-Scope. The device operates on a 7.2 VDC battery pack or 10-16 VDC external power, weighing 255 grams with dimensions of 58x88x27 mm. The VX-5R was also available as the metallic silver VX-5RS.
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Fill out the form to design a bandpass filter as described in the January 1985 issue of Ham Radio Magazine. These filters are generally limited to frequencies above 200 MHZ because their size is slightly longer than 1/4 wavelength
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Project of receive only filters optimized for minimal loss and very high rejection of frequencies below 75% of the filter center frequency by K1TTT
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Frequency allocation in Santa Barbara California
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The KP3AV Systems website offers a detailed listing of amateur radio repeaters across Puerto Rico, including operational frequencies and tones for VHF and UHF bands. It features sections dedicated to digital modes like DMR and C4FM, as well as information on FRS, GMRS, and MURS. The resource also includes articles on emergency communications protocols and provides access to Spanish-language manuals for various radio equipment. Recent content covers the new open-source FT2 mode for WSJT-X Improved, upcoming 60-meter band frequency allocations and power restrictions effective February 13, 2026, and discussions on 2-meter contacts with Desecheo Island from Puerto Rico. The site also presents U.S. amateur radio band plans and highlights local contesters like Manuel WP4TZ, offering practical insights into portable operations and contest participation.
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The X80 multi-band HF vertical antenna, a commercial iteration of the Rybakov design, exhibits a physical length of 5.5 meters, or approximately 18 feet, and is constructed from aluminum tubing. It operates as a non-resonant vertical, requiring an external antenna tuner for impedance matching across its intended operating frequencies. The antenna's design incorporates a 1:4 UNUN at its base, facilitating a nominal 50-ohm feed point impedance for the coaxial cable. Performance observations indicate effective operation on 40 meters, 20 meters, 15 meters, and 10 meters, with reduced efficiency on 80 meters and 160 meters due to its relatively short electrical length for these lower bands. Comparative analysis with a G5RV dipole and a half-wave end-fed antenna reveals the X80 offers a lower take-off angle, beneficial for DX contacts, particularly on the higher HF bands. Field tests conducted with an Icom IC-706MKIIG transceiver and an LDG AT-100ProII autotuner demonstrate the X80's ability to achieve acceptable SWR across 80m through 10m. The antenna's compact footprint and ease of deployment make it suitable for restricted spaces or portable operations, though its performance on 80 meters is noted as a compromise compared to full-size resonant antennas.
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List of scanner frequencies used in the US for emergency or inter-agency communications, allocated nationally.
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Demonstrates the operational status and reception reports for the SK6RUD/SA6RR QRPP beacons, which transmit on 478.9 kHz, 1995 kHz, 10.131 MHz, and 40.673 MHz. These beacons utilize extremely low power, with the 630-meter beacon operating at approximately 0.1 watt ERP into an L-antenna, showcasing the potential for long-distance contacts under favorable propagation conditions. The site details the specific frequencies and antenna types employed, such as a vertical at 500 kHz and a 1/4 vertical for higher bands. The resource compiles over 10,530 reception reports from amateur radio operators worldwide, logging details such as date, time, band, RST signal report, locator, distance, and receiver setup. Notable long-distance reports include a 500 kHz reception by AA1A-Dave from 5832 km in 2008 and a 10.133 MHz reception by ZL2FT-Jason from 17680 km in 2010, illustrating the global reach of these low-power transmissions. Each log entry provides specific equipment used by the reporting station, including transceivers like the Yaesu FT817, ICOM IC-7300, and various antenna configurations such as coaxial mag loops, inverted Ls, and end-fed wires. The primary objective of the SK6RUD beacons is to challenge conventional notions of power requirements for effective two-way communication, proving that contacts over significant distances are achievable with minimal output. The site also includes a submission form for new reception reports, fostering community engagement and continuous data collection on propagation phenomena across different bands. The detailed logs offer practical insights into real-world propagation characteristics and the efficacy of QRPP operations.