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- Radio Equipment > HF Amplifiers > Acom 1000
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- Antennas > Bazooka
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- DX Resources > Contest Calendars
- Operating Modes > D-STAR > D-Star Clubs
- Radio Equipment > HF Transceivers > Icom IC-7700
- Radio Equipment > HF Transceivers > Icom IC-7851
- Technical Reference > Mic wiring
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- CB Radio > References
- Radio Equipment > Reviews and Comparisons
- Ham Radio > Clubs > North America > USA > Vermont
- Radio Equipment > HF Transceivers > X1M
- Radio Equipment > HF Transceivers > XIEGU G90
- Radio Equipment > HF Transceivers > Yaesu FT-818
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The Bristol Amateur Radio Club's purpose is to: Facilitate the exchange of information and general cooperation between members to promote amateur radio knowledge, fraternalism and individual operating efficiency
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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.
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The Utility DXers Forum (UDXF) provides a centralized platform for exchanging news and information concerning utility radio stations and signals operating within the 0 to 30 MHz spectrum. It specifically excludes broadcasting, pirate, and amateur radio transmissions, concentrating instead on a diverse array of other signals. The resource details the types of stations covered, including maritime coastal and ship stations, aeronautical ground and aircraft communications (voice, HFDL, Selcalls, Volmet), military operations, various beacons (NDB, driftnet, propagation, pirate, high-frequency), fax transmissions, numbers stations, diplomatic communications, clandestines, and other unusual signals. Further content addresses radar systems such as Over-the-Horizon, Ocean Wave, and CODAR, alongside ionosondes, chirpsounders, ALE-systems, Selcall-systems, and tone calls. Experimental stations and standard frequency and time stations are also within its scope. The forum also acknowledges utility radio-related amateur events like the International Lighthouse Weekend and Night of Nights, providing a broader context for listeners. The site offers sections for modes, hardware, software, a utility radio archive, digital BC & HF conditions, and a utility radio club archive, along with QSLs and pennants.
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Specialized in manufacturing measurement instruments for more than 25 years. Clamp meter, digital multimeter, analog panel meter, thermometer, and led panel meter
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Wide selection of quality, affordable shipping cases including stock and custom, heavy duty, pelican protector, removable top, wheeled, ATA, and more!
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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.
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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.
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A 144 to 148 MHz J-pole antenna, optimized for base station use, is presented with detailed construction plans. This slim, omnidirectional, half-wave antenna is fed at the end through a quarter-wave shorted transmission line, drawing inspiration from the classic _Zepp antenna_. The design emphasizes achieving a 1:1 VSWR and good efficiency on the 2m band, noting that even a one-percent error in calculation can significantly impact performance. The article provides specific dimensions in inches for the radiator, quarter-wave section, and feed point, along with a parts list for construction from inexpensive materials, estimated at approximately **$10** total cost. The resource offers practical construction tips covering copper pipe selection, L and T joint variations, and detailed soldering instructions using a propane torch. It addresses feedline attachment, the critical role of a four-turn, _5-inch diameter_ choke to prevent coax radiation, and proper antenna fastening techniques, including grounding for lightning protection. The author explicitly advises against scaling the design for other bands due to potential efficiency loss and offers guidance on corrosion protection. The antenna design has been released into the public domain for private amateur use.
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A quad turnstile consists of two cubical quad loops oriented in a diamond configuration and angled 90 degrees apart from one another with both diamonds sharing the same top and bottom points
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On March 27, 2017, the FCC adopted final rules for the USA 630-meter band, detailed in Report and Order FCC 17-33, which required PLC coordination with the Utilities Telecom Council before amateur operations could commence. This resource documents the WD2XSH experimental group's activities, including authorized stations, band plans, and frequency assignments within the 465-515 KHz range, with many stations operating between 495-499 KHz and 501-510 KHz. The site also highlights the WRC-12 decision on February 14, 2012, which granted a new **7-kilohertz-wide** secondary allocation between _472-479 kHz_ for the Amateur Radio Service worldwide. The group's efforts included operating with a maximum ERP of **20 Watts** across 45 stations in the continental USA, Alaska, and Hawaii, using emission modes such as CW, PSK-31, FSK-31, and MSK-31. The site provides links to download FCC 17-33 in PDF and DOCx formats, and offers a station location map, a list of stations by callsign and frequency, and an archive of news updates. Reception reports for any 600-meter station are encouraged to help the amateur radio community understand propagation and repeatability on this challenging band.
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A page describing how to setup a magnetic loop antenna with the DIY Magnetic Loop Starter Kit produced by Chamaeleon Antenna. Includes a video and a detailed instructions to setup.
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Fifty-three digital modes, including PSK31, RTTY, and JT65, are explored in this resource, providing detailed descriptions of their underlying technologies and typical use cases. It covers error correction methods like ARQ in PACTOR and FEC in JT65, alongside modulation schemes such as FSK and PSK. The content highlights the evolution of digital communication from traditional TNC-based systems to modern sound card implementations, emphasizing the role of personal computers in advancing these modes. Specific modes like AMTOR, PACTOR, and G-TOR are discussed, noting their baud rates and error correction capabilities. For instance, AMTOR operates at 100 baud, while PACTOR offers 200 baud with Huffman compression. The article also delves into newer modes like MFSK16, which uses 16 tones and continuous Forward Error Correction, and Olivia, capable of decoding signals 10-14 dB below the noise floor. Each mode's bandwidth, speed, and resilience to propagation challenges are examined, such as MT63's 1 KHz bandwidth and 100 WPM rate, or Hellschreiber's 75 Hz bandwidth and 35 WPM text rate. The resource also lists predominant USA HF digital frequencies for bands like 160, 80, and 40 meters, specifying segments for PSK31, RTTY, SSTV, and Packet. It includes links to freeware and shareware sound card software such as Digipan, FLDigi, and MixW, enabling amateurs to experiment with these modes.
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This resource documents numerous QRP (low power) portable amateur radio operations conducted by W1PID, Jim Cluett, primarily from various outdoor locations in New Hampshire. The content includes detailed accounts, photographs, and operational specifics for over 350 individual "QRP Adventures," often involving hiking, biking, or kayaking to remote sites. Each entry typically highlights the location, date, bands and modes used (frequently CW on HF), and notable DX contacts made with minimal power, sometimes as low as 200mW WSPR. The site serves as a chronicle of practical QRP field operation, demonstrating successful DXing and contesting from challenging environments. It showcases diverse operating scenarios, from mountaintops like Cannon Mountain and Knox Mountain to lakeshores, riverbanks, and even marine mobile operations. The documented contacts span numerous DXCC entities across Europe, Asia, and the Americas, providing empirical evidence of QRP's efficacy in varied propagation conditions and terrains. Specific events like the Worked All Germany contest, 13 Colonies Event, and CWT sprints are also featured.
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Kits for AM FM radio, UHF control, big LED displays, games, controls, timers, chasers and flashers
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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.
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The alabama historical radio society - come visit our website and museum where we have a large collection of antique radios. our club does coil winding, has a large library, and a wealth of knowledge in our members.
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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.
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Installing a mobile rig in a vehicle requires careful planning and execution to ensure optimal performance and safety. The process begins with selecting the right equipment, such as the ICOM IC706MKII for low bands and the ALINCO DR-610 for VHF/UHF operations. Proper mounting is crucial; both radios are strategically placed under the back seat of the Silverado, allowing for a clean installation while maintaining passenger comfort. The Hustler antenna, equipped with various resonators, ensures coverage across multiple bands, while the LDG automatic antenna tuner fine-tunes the match for efficient operation. A remote head for the tuner enhances accessibility, making adjustments easier while driving. Each step of the installation is documented to provide insights and tips for fellow operators looking to enhance their mobile setup. The experience shared here reflects practical knowledge gained through hands-on work, aiming to inspire others in the ham community to undertake similar projects.
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The MFJ-971 portable antenna tuner, as stock, lacks a bypass switch and sufficient inductance for efficient 1.8 MHz operation. This modification addresses these limitations by integrating a DPDT switch for direct signal bypass, enhancing operational flexibility. Furthermore, the guide details the addition of a T130-2 iron powder toroid, wound with **29 turns** of enamelled copper wire, to augment the tuner's internal inductance. This increases the maximum inductance from approximately 17µH to around **27µH**, enabling effective impedance matching on the _160-meter band_. The modification involves cutting the wire after the 'L' tap on the original inductor and inserting the additional toroid, ensuring the entire original coil plus the new inductance is engaged when 'L' is selected. This preserves the functionality of other inductance settings while extending low-band performance. The article also highlights a potential RF burn hazard from the variable capacitor nuts on the MFJ-971, even at QRP power levels.
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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.
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This antenna was conceived mainly for high-speed digital transmission via satellite. The antenna is made of two full waves loops , mounted at right angles to each other. Then coupled together, 90 degrees out of phase over a horizontal circular reflector. With this configuration the antenna is omni directional and circularly polarized.
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Michigan Antique Radio Club, or MARC. The MARC was officially founded October 19, 1985 at the Dillon Inn (now the Hampton Inn) in Lansing, Michigan. Our mission: To preserve the history and enhance the knowledge of radio, television and related disciplines
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Fixing the problem with VHF-LED coming on while transmitting UHF
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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.
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The Rochester Amateur Radio Club, Incorporated (RARC) is an ARRL affiliated club located in Rochester, Minnesota. The purpose of the radio club is to: advance general interest and knowledge of amateur radio
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Details the Big Thunder Amateur Radio Club (BTARC), a long-standing amateur radio organization based in Boone County, Illinois, established in 1962. It covers the club's mission to enhance the skills of local hams, promote radio knowledge, and foster social interaction among operators. The resource outlines BTARC's commitment to community service, including emergency communications support through RACES, and its active participation in events like Field Day, fox hunts, and public service communications for local races. Explains the club's history, including the establishment of its first repeater in the 1970s by members WD9JGH, Mike George, K9ORU, and Claude Horsman, WB9PMM, using a VHF Engineering kit and a Sinclair duplexer. It provides specifications for two club-maintained FM repeaters: a 2-meter repeater on 147.375 MHz (+600 KHz shift, 100.0 Hz PL tone) and a 70-cm repeater on 442.825 MHz (+5 MHz shift, 114.8 Hz PL tone). The club hosts a weekly 2-meter net on Sundays at 7:00 PM local time and holds monthly meetings on the second Thursday at the Spring Township Building in Belvidere, IL.
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Fostering community spirit and recognizing contributions within amateur radio clubs often involves tangible tokens of appreciation. **Challenge coins** have emerged as a popular and effective method for achieving these goals, providing a unique way for clubs to acknowledge member participation and milestones. These custom-designed coins can reflect a club's specific identity and achievements, serving as a physical representation of membership and dedication. Clubs can utilize these coins for various purposes, including recognizing membership renewals, commemorating event participation like Field Day, or even as a fundraising mechanism to support club activities and repeater funds. The customization options extend to plating and color, allowing for different tiers of recognition, such as bronze for general membership, silver for life members, or gold for special awards presented by club officers. This flexibility makes them a versatile tool for enhancing engagement. Beyond traditional amateur radio clubs, organizations like the **Military Auxiliary Radio System (MARS)** also benefit significantly from challenge coins, reinforcing their connection to the broader military and amateur radio communities. The production process is simplified with artwork assistance, ensuring clubs can easily bring their unique designs to fruition.
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Decode DTMF from your iPhone. Hold your smartphone close to a DTMF source and this app will decode the numbers being dialled.
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Article on antenna feed impedance and the importance of matching RF andtennas to feeders, including notes on Radiation resistance, loss resistance, and efficiency are also detailed.
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An interesting article about amateur radio portable operations with excellent pictures. Setup includes a 60 watts of portable solar power being controlled by a charge controller, and a batteries powering an FT-897D.
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This resource provides a discussion group platform for amateur radio operators interested in APRS within Argentina. It facilitates technical discussions, sharing of operational experiences, and coordination among users of the Automatic Packet Reporting System in the region. The group serves as a central point for exchanging information on local digipeater networks, IGate deployments, and mobile tracking applications, covering both hardware and software aspects relevant to APRS implementation. The forum enables members to post questions, offer solutions, and disseminate news related to APRS activities specific to Argentina, fostering a community-driven approach to problem-solving and knowledge transfer. It supports the collaborative development and maintenance of the APRS infrastructure, allowing for real-time interaction on topics such as frequency usage, network topology, and integration with other amateur radio services.
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In this article the author shows the receiving loop antenna for 160 meters band installed at his QTH. Diagram and movie available. Article in in Turkish but can be translated in english
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The Union Métropolitaine des Sans-filistes de Montréal (UMS) operates daily nets on **VE2REM** 147.015+ T103.5, **VE2RYV** 146.655- T141.3, and **VE2RVK** 145.430- T141.3, alongside Echolink VE2UMS-L and DMR TG302273. This Montreal-based club, representing hundreds of radio amateurs, provides information for those interested in amateur radio and serves as a communication hub for its members, including a regularly visited ham radio flea market section. The site also highlights significant club initiatives like the AREDN Mesh Network modernization project and an innovative after-school program. The UMS website details upcoming events such as the 2026 sugar shack invitation, Field Day 2025, and monthly meetings scheduled for September 18, 2024. It also features a live log sheet section and a WEB SDR, offering practical tools for members and visitors. The club's president, Bruno VE2VK, extends a welcome, emphasizing the UMS's role in fostering amateur radio in the greater Montreal region, with contact information provided for inquiries.
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Constructing a high-performance RF spectrum analyzer up to 1000 MHz requires careful attention to component selection, shielding, and circuit isolation. This resource details a project that improves upon the _Spectrum Analyzer for the Radio Amateur_ design by Wes Hayward (W7ZOI) and Terry White (K7TAU), incorporating ideas from Scotty Sprowls' project, particularly his 1013.3 MHz IF bandpass cavity filter. The analyzer utilizes a Mini-Circuits SRA-11 mixer with a sweeping local oscillator from 1013 to 2013 MHz, feeding into a 4-pole copper pipe cavity filter. The design employs a second SRA-11 mixer with a fixed 1024 MHz LO to produce a 10.7 MHz final IF. This signal then passes through narrowband resolution filters and is processed by Analog Devices AD603 and AD8307 ICs for IF amplification and logarithmic detection, driving an oscilloscope in X/Y mode. The project emphasizes modular construction, using salvaged components and double-sided FR4 material for PCBs, with critical notes on minimizing spurious images through effective shielding and proper voltage regulation for each module. Key components include a Z-Communications V585ME48 VCO for the first LO and a Z-Comm V583ME01 VCO controlled by a Motorola MC145151 PLL for the second LO. An optional Hittite HMC307 step attenuator and K&L 5L121-1000/T5000-O/O low-pass filter manage RF input. Tuning procedures for the 10.7 MHz IF resolution filter are also detailed, showing before-and-after spectrum views.
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A very well done presentation about End-Fed Half-Wave antennas. This PDF document contains a summary of experiences in how to build custom EFHW antennas. Includes an interesting comparison table of UnUn configurations with recommended toroids, Wire size, turns and capacitors. An useful recap on common errors in building homebrew EFHW Ununs completes the document.
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In this article the author analyze six different type of VHF handheld antennas and as result of his self training on his new vector network analyzer published this interesting report
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This resource is an online tutorial focused on setting up the Raspberry Pi for amateur radio applications. It covers the installation and configuration of various software packages tailored for digital communications and protocols, including _Packet Radio_ with Hamlib and Direwolf, as well as data modes like FLDigi and WSJT-X. The guide also details the integration of hardware components such as GPS clocks for time synchronization and real-time clocks for enhanced functionality. Users will find instructions for installing software like GPredict for satellite tracking and GQRX for software-defined radio (SDR) applications. The tutorial emphasizes practical steps, including the use of command-line inputs in the Raspberry Pi OS terminal, and provides troubleshooting tips for common issues such as faulty SD cards or insufficient power supplies. Operators are encouraged to explore various applications, including APRS iGates and WSPR beacons, to enhance their ham radio experience. The material is designed for licensed amateur radio operators with basic knowledge of electronics and computing.
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Over 1900 ARISS school events have been conducted since 2000, facilitating amateur radio contacts between students and ISS crew members. This resource details the Amateur Radio on the International Space Station (ARISS) program, outlining scheduled contacts, operational procedures, and application processes for educational institutions worldwide. It lists specific upcoming contacts, such as those with Lewis Center for Educational Research in California and Vauban, Ecole et Lycée français de Luxembourg, typically operating on a 145.800 MHz downlink frequency. The content also provides crucial guidelines for radio amateurs, emphasizing the importance of not interfering with scheduled school contacts and utilizing the crossband repeater for general QSOs when available. It clarifies crew availability for casual contacts, noting that astronauts are usually free during personal time, approximately one hour after waking and one hour before sleeping, and often on weekends. Constraints on scheduling, such as avoiding EVA weeks and specific crew rest periods, are also detailed. Furthermore, the resource includes historical statistics on direct versus telebridge contacts, QSL information, and links to related ARISS, AMSAT, ARRL, and NASA websites. It also provides information on applying to host an ARISS contact for schools and youth organizations in various regions, including the United States, Europe, Africa, the Middle East, Canada, Central and South America, Asia, and Australia.
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Knowledge and guide on Amateur Radio mix in Malay & English Language for Malaysian SWL & Amateur Radio Operator.
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Maintaining vintage Eddystone receivers often presents unique challenges, as detailed by Victor Jenkins in his refurbishment of an EA12, where his deep understanding of RF circuits ensures optimal performance for daily shortwave listening. Similarly, Gerry O’Hara VE7GUH, a prolific contributor to the EUG website and a trustee, meticulously documented his restoration of an Eddystone S830/2, even addressing an unusual instability issue with a follow-up postscript article and YouTube videos demonstrating the fix. His work, along with numerous other articles on the "Restorations" page, showcases a master's approach to bringing vintage sets back to factory specifications or better. Beyond technical restorations, the EUG also shares compelling historical narratives. One such story recounts the discovery of a long-lost 78rpm recording featuring Eddystone Radio Ltd.'s founder, George Stratton Laughton, and other key figures discussing the company's wartime and post-war contributions to shortwave communications. This six-minute BBC production, transcribed into an MP3 file by Peter Carney, offers a rare auditory glimpse into the company's legacy, highlighting its role in supplying equipment to police, ministries, and expatriate British workers. The community aspect thrives through shared experiences, like Roger Trickett's anecdote about his Eddystone EC10, which has been continuously powered for 50 of its 54 years, traveling across continents and enduring various modifications. Another intriguing account from Roy GM4VKI details the "S640 Identity Crisis," where a seemingly standard S640 receiver turned out to be a masterfully engineered 80/20-meter SSB transceiver built into the original chassis by GI3ZX, showcasing incredible ingenuity from a bygone era of amateur radio.
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Designing and constructing a two-element receiving loop antenna array for HF operation involves specific considerations for achieving high directivity and noise reduction. This resource details a homebrew system comprising two 30-inch diamond-shaped loops, spaced 20 feet apart, which are fed through mast-mounted preamplifiers and passive signal combiners. The operational principle relies on adjusting phase delays between elements via precise _Belden 8241_ coaxial cable lengths, optimized for specific bands from 160m to 20m. Performance data, derived from _EZ-NEC_ modeling, illustrates consistent 90° azimuth-plane beamwidth and low take-off angles across the target bands, with _Receiving Directivity Factor_ (RDF) values comparable to a 300-foot Beverage antenna. The article presents detailed elevation and azimuth plots for 20m, 30m, 40m, 80m, and 160m, demonstrating the array's ability to provide strong response at low DX angles while also supporting _NVIS_ signals. Key components like the _DX Engineering RPA-1_ preamplifier and _DXE RSC-2_ signal combiner are discussed, alongside the importance of impedance matching to preserve antenna patterns. The construction emphasizes self-contained elements that do not require ground radials, offering a compact solution suitable for suburban environments and stealth installations, with a focus on optimizing receive performance independently from transmit antennas.
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Articles for the sight impaired
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The **LDG Z100 Autotuner** review by GW6ITJ details the unit's practical application and performance in a ham shack environment. Initially acquired to replace an MFJ-902, the Z100 is noted for its ease of use, though the author observes it doesn't quite match the impedance range of the older MFJ unit. This hands-on assessment provides a real-world perspective on its capabilities for 100-watt operation across the HF bands. GW6ITJ specifically mentions the Z100's suitability for 3.5 MHz and higher frequencies, indicating its utility for common HF operations. The review focuses on user experience rather than technical specifications, directing readers to the LDG website for detailed data and manuals. This approach highlights the tuner's operational characteristics from a user's perspective. The author's experience with the Z100 suggests it's a reliable choice for general amateur radio use, particularly for those seeking a straightforward autotuner. The comparison to the MFJ-902 offers a valuable benchmark for hams considering a similar upgrade or new acquisition, emphasizing practical differences in impedance matching.
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Wfview is a program that allows many modern Icom ham radio transceivers (such as the IC-7300, IC-9700, IC-7610, IC-R8600 and many others) to be controlled via a computer. wfview shows the gorgeous spectrum display on whatever display is connected, including projectors, touch screens, and TVs. wfview allows for full radio control from a computer keyboard and basic control from a numeric keypad. It works under Windows, Linux and MacOS
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Presents an alternative construction method for isolated element Yagi antennas, specifically for VHF/UHF operation. The technique utilizes commercially available vibration damping clamps (resin support blocks) to isolate 1/4-inch aluminum rod elements from a 1-inch square aluminum boom, simplifying the build process by eliminating the need for custom-machined insulators. This approach is demonstrated through the construction of 6-element Optimized Wide-Band (OWA) Yagis for the 2-meter, 1.25-meter, and 70-centimeter bands, which are well-suited for portable contesting arrays due to their light weight and decent gain. The document provides detailed specifications for element and boom materials, along with step-by-step procedures for cutting, drilling, and tapping. It also covers the fabrication of a feedpoint bracket for a direct 50-ohm SO-239 coax connection and discusses considerations for horizontal versus vertical polarization, including mast placement. The resulting 6-element models achieve an average free-space gain of 10.2 dBi and a 25 dB front-to-back ratio, with the construction technique being scalable for higher gain designs. Included are parts lists with sources, detailed mechanical drawings for each band, and EZNEC data for the 2-meter and 70-centimeter designs, showing both free-space and 30-foot elevation performance. The designs are optimized from W4RNL's original concepts using HAMCALC, ensuring good gain, passband characteristics, and front-to-back ratios for wideband Yagi operation.
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This simple antenna was installed on the attic. Antenna was matched with help an Automatic ATU in 40, 30, 20, 17, 15, 12 and 10 meter amateur Bands. The Antenna worked satisfactory on the above mentioned bands.
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The antenna described in this article is for 50 MHz, but the design can be scaled for any band, including VHF, UHF, or even the higher HF bands. The antenna is nothing more than a square loop of wire, approximately 30" (or ~76cm) per side. The loop is fed in the middle of one side, and the opposite side to the feed point has a gap in it.
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Tutorial about writing a software SSTV modulator/demodulator using slant correction and several improvements. It requires programming language knowledge and programming skills.