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Query: pic power meter
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The project details a DIY SWR/Wattmeter designed around an _Arduino Uno_ shield, providing capabilities to measure RF power from 2 to **200 watts** and Standing Wave Ratio (SWR) for HF amateur radio bands. This construction features a compact design, integrating the measurement circuitry directly onto a custom PCB that interfaces with the Arduino Uno microcontroller. Key components include a directional coupler for sensing forward and reflected power, precision rectifiers, and analog-to-digital conversion for processing RF signals. The Arduino firmware handles calibration, calculations, and displays the results on an integrated LCD, offering real-time feedback on antenna system performance. The design prioritizes simplicity for homebrewers. Performance specifications indicate accurate readings within the **2-200W** power range, suitable for typical QRP to medium-power HF operations. The project provides schematics and a basic overview of the software logic.
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Presents a catalog of **QRP** transceivers, antenna tuners, and related accessories for amateur radio operators. The product line includes the ZM-2 antenna tuner, designed for efficient impedance matching across HF bands, and the NW-series QRP transceivers, offering low-power CW operation. Additionally, the site details various ladder line insulators and specialized connectors, emphasizing robust construction for field deployment and home station use. Each product listing provides specifications, operational parameters, and pricing information. Compares the features of different **QRP transceiver** models, such as the NW-40 and NW-20, highlighting their respective band coverage and power output capabilities. The ZM-2 tuner's performance is detailed with typical SWR reduction figures for various antenna types, demonstrating its utility for portable and fixed stations. Customer testimonials and product images illustrate the practical application and build quality of EMTECH's offerings, providing insights into their durability and ease of integration into existing amateur radio setups.
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The KD1JV "Melt Solder" Digital QRP SWR/Power Meter operates across the 160m to 6m bands, featuring 9.9-watt and 990-milliwatt power scales, a peak hold mode for SSB, and a VSWR scale from 1:1 to 9.9:1. It utilizes a _Stockton directional coupler_ wound on a single binocular core and an _Atmel AVR ATtiny26L_ microcontroller for processing. The design incorporates _W7EL diode compensation_ in a non-inverting amplifier feedback loop to address diode voltage drop and non-linear behavior at low power levels, with software corrections applied for improved accuracy, particularly at QRP power levels up to 5 watts. Construction details include parts placement, transformer winding instructions for #26 magnet wire, and calibration procedures using a 1.5V alkaline battery or an oscilloscope with a 50-ohm dummy load. Packaging options are discussed for fitting the board into an Altoids tin or a deeper Whitman’s Sampler tin, with considerations for battery life extension by adding a third or fourth battery. Accuracy tests performed at 7 MHz compare readings against a True RMS power meter based on an _Analog Devices AD8361_ chip, showing typical deviations of 0-5% across various power levels.
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Presents the design and construction details for a VHF bicycle-mobile antenna, originally published in QST. The antenna utilizes a modified _Arrow J-Pole_ design, adapted for portable operation on a bicycle frame. Performance characteristics include a reported **1.5:1 SWR** across the 2-meter band, demonstrating effective impedance matching for typical handheld transceivers. Construction involves readily available materials, emphasizing lightweight components suitable for mobile deployment. The document provides a parts list and step-by-step assembly instructions, detailing the radiator and ground plane element lengths for optimal resonance at 146 MHz. Mechanical considerations for mounting on a bicycle are also addressed. The resource covers practical aspects of integrating the antenna with a bicycle, including cable routing and securing methods. It offers insights into achieving reliable VHF communications while operating in a mobile, low-power environment, making it relevant for field day activities or casual portable operation.
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A PIC16F876 microprocessor-based digital SWR/WATTmeter project provides automatic operation across the 1.8 to 60 MHz frequency range. This design displays both SWR and P.E.P. power values, incorporating a bar graph on the second LCD line for instantaneous power tracking. The directional coupler utilizes a single-wire coil on a ferrite FT50-43 toroid, balanced with a 60 pF trimmer, and employs 1N5711 Schottky diodes for detection, ensuring linearity and a power range of 5 to 120 W. The software, developed by IW3EGT, compensates for diode voltage drop for precise readings, updating power every two seconds for stable display of modulated carriers, while the bar graph updates ten times per second for near real-time feedback. Calibration involves two phases: adjusting the directional coupler for minimum SWR on a 50-ohm dummy load at 28 MHz, and calibrating the microprocessor system by inputting a calculated power value (Power (Watt) = (Vout + 0.5)^2 / 100) at 14-21 MHz. The project includes PCB layouts for both the directional coupler (two-layer copper board) and the PIC module (single-sided), with specific instructions for component placement and shielding to prevent RF interference. The design allows for modification of power reading capability by varying the number of turns in the coupler coil, catering to different power levels.
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Details a practical QRP wattmeter construction, leveraging a simplified SWR meter design by JA6HIC. The project focuses on a forward-only power measurement circuit, providing a functional instrument for RF power levels from milliwatts up to 5 watts. It maintains a 50-ohm input and output impedance, suitable for typical QRP transceivers and antenna systems. The resource includes the schematic for the "VSW" (Very Simple Wattmeter) and outlines a six-step alignment procedure. This calibration process involves using a known RF source up to 5W, setting full-scale deflection, and marking power increments. It also addresses minimizing frequency effects on readings with a 100pF trimmer capacitor, noting that measurement error is highest at the lower end of the scale. Construction notes mention using a piece of RG-213 coaxial cable for the inductance and coupler, with the wattmeter assembled in early 2003. The author provides an example measurement showing 0.8W into a dummy load and 1W into a 3-element beam.
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Well documented Amateur Radio HF/VHF antenna projects, high power Russian GS35B RF amplifiers, mobile RFI solutions, related accessories, vintage radios, Six meter equipment, and useful techniques by K8CU are inside.
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An antenna does not have to be resonant to work, as the primary reason for resonance is to eliminate the need for an impedance-matching device. A non-resonant wire dipole fed with open-wire line and an antenna tuner can function as an effective multiband antenna. Two wires are essential for powering an antenna, ideally with a balanced configuration like a dipole fed by parallel-wire line, though coaxial cable can be used with a 1:1 balun to mitigate RF feedback on the shield. Antenna gain is achieved by shaping and aiming RF energy, concentrating it in a particular direction, as seen in beam antennas or shaped radiation patterns of wire antennas. The function of an antenna tuner is to match the transceiver's 50 Ohm output to the antenna system's impedance, which can vary widely. Wire antennas do not always require center feeding; end-fed long wires or off-center-fed dipoles (Windom antennas) can be used, often requiring a counterpoise or radial system. Dipole antennas do not need to be perfectly horizontal; their legs can be bent, inclined, or even vertical, affecting feed point impedance. Vertical antennas shorter than a half wavelength necessitate a ground system, typically comprising radial wires, with more radials generally leading to greater efficiency. A 1:1 SWR indicates an impedance match but does not guarantee a good antenna, as an inefficient antenna with a poor ground system can still show a perfect SWR while wasting RF as heat. Always using the best feed line affordable is crucial for minimizing loss and maximizing RF signal delivery to and from the antenna.
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Pictures and circuit diagramm to build this power amplifier for 2 meters
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The article "Exploring the World of 10 Meter Beacons" by Ken Reitz, KS4ZR, provides an in-depth look at 10-meter beacon operations, focusing on their utility for propagation analysis. It details FCC Rules part 97.203 governing beacon stations, including license requirements, power limits (under 100 watts), and the specified band segment of 28.200-28.300 MHz for U.S. operations. The content highlights the diversity in beacon construction, from converted CB radios to home-brew QRP transmitters, and discusses the robust operating conditions these 24/7 stations endure. The resource presents several case studies of active 10-meter beacon operators like Ron Anderson KA0PSE/B, Domenic Bianco KC9GNK/B, and Bill Hays WJ5O/B, detailing their equipment, antenna setups, and typical signal report volumes. It also introduces the NCDXF/IARU International Beacon Project, which features 18 synchronized beacons worldwide transmitting on 28.200 MHz at varying power levels (100W, 10W, 1W, 100mW) to facilitate propagation testing. The article also covers the PropNet Project utilizing PSK31 on 28.131 MHz and the 250 Synchronized Propagation Beacon Project on 28.250 MHz. Practical advice for monitoring includes using the RST reporting method, understanding the impact of the solar cycle on 10-meter propagation, and tips for setting up a personal beacon, such as frequency selection and power output considerations. The IY4M Guglielmo Marconi Memorial Beacon Robot on 28.195 MHz is also mentioned for its automatic QSO mode. The article concludes with a list of other resources for 10-meter beacon information.
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This resource details the construction of a versatile CW/QRSS beacon, designed around a Microchip _PIC16F84_ microcontroller. The project provides a flexible platform for transmitting either standard CW or very slow QRSS signals, making it suitable for LF, VHF, UHF, and SHF applications. It supports two distinct messages, each configurable for speed (from 0 to **127** WPM for CW, or up to **127** seconds per dot for QRSS) and repetition within a six-phase sequence. The core functionality relies on the PIC's EEPROM, which stores all operational parameters, including message content, transmission speeds, phase configurations, and relay control settings. This design allows for parameter modification directly via programming software like _ICProg_ without altering the main program code. The project includes a detailed schematic, a component list, and an explanation of the EEPROM memory mapping for messages, speeds, phase settings, and inter-phase delays. General-purpose outputs (OUT1, OUT2, OUT3) provide dry relay contacts for external control, enabling functions such as power switching, antenna selection, or frequency changes. A 'TRIGGER' input facilitates controlled starts or continuous free-run operation. Sample EEPROM configurations illustrate how to program specific beacon sequences, including message content and relay states.
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The 11-meter band, often associated with Citizens Band (CB) radio, presents unique challenges and opportunities for long-distance communication, particularly for operators interested in DXing. This group facilitates discussions and information exchange among enthusiasts who operate on this frequency, often utilizing single-sideband (SSB) modulation for improved range and signal clarity compared to traditional AM CB operations. The community provides a platform for members to share experiences, technical insights, and propagation reports relevant to 27 MHz operations. Members engage in discussions covering various aspects of 11-meter DX, including antenna configurations, transceiver modifications, and operating techniques to maximize signal propagation across continents. The forum serves as a central hub for coordinating contacts, sharing QSL information, and celebrating successful long-haul QSOs. Specific topics often include optimizing power output, reducing noise, and understanding solar cycle effects on 27 MHz. The group's activities extend to organizing virtual gatherings and promoting ethical operating practices within the 11-meter DX community. It supports both seasoned operators and those new to the band, fostering a collaborative environment for exploring the capabilities of CB radio beyond local communications.
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The Japanese Amateur Radio Teleprinter Society (JARTS) serves as a central hub for RTTY and PSK31 enthusiasts in Japan, providing essential information regarding its annual JARTS RTTY Contest. The resource outlines contest rules, exchange parameters, and scoring specifics, enabling participants to prepare effectively for the event. It also offers insights into the club's broader activities and its role in promoting digital mode operations within the amateur radio community. The site details the contest's operational periods and categories, which typically include single-operator, multi-operator, and SWL entries, often with power output classifications. Participants can find guidelines for log submission and result publication, ensuring adherence to the contest's administrative requirements. The JARTS RTTY Contest is a significant event for digital mode operators, drawing participation from across Asia and beyond. Beyond contest specifics, the resource provides historical context for JARTS, highlighting its foundational role in Japanese amateur radio digital communications. It serves as a primary point of contact for members and prospective participants, fostering engagement in RTTY and PSK31 modes.
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A fractional bandwidth of up to 30:1 characterizes spiral antennas, making them highly effective across a very wide frequency range, often from 1 GHz to 30 GHz. The resource details two primary types: the **Log-Periodic Spiral Antenna** and the **Archimedean Spiral Antenna**, defining each with specific polar functions and illustrating their planar configurations. It explains that spiral antennas are typically circularly polarized, with a Half-Power Beamwidth (HPBW) of approximately 70-90 degrees, and a peak radiation direction perpendicular to the spiral plane. The content elaborates on critical design parameters affecting radiation, including the total length (outer radius) for lowest frequency, the flare rate ('a' constant) for optimal radiation versus capacitive behavior, the feed structure (often an infinite balun) for high-frequency operation, and the number of turns (typically 1.5 to 3 turns). It also discusses the theoretical impedance of 188 Ohms for Log-Periodic spirals, derived from Babinet's Principle, noting actual impedances are often 100-150 Ohms. The article presents a simple construction method for an Archimedean spiral, demonstrating VSWR and efficiency measurements. Measurements from a constructed spiral antenna show a VSWR that is fairly constant across the band, albeit with a mismatch loss of about 3 dB. The antenna efficiency remains around -5 dB (31.6%) across its operating range, indicating a decent wideband radiator despite opportunities for optimization.
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This article loaded with nice pictures and schematics, describes a 160-10 meter linear amplifier that uses a pair of 3-500Z triode power tubes. It was designed and constructed by William Moneysmith, W4NFR. The amplifier features fast warm up and 1500-Watt RF output with 100-Watts of drive.
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Showcasing a specialized product line, Advanced Receiver Research presents a comprehensive catalog of **low noise preamplifiers** and microwave **Gunnplexers**. The offerings span a broad spectrum of radio frequencies, from VLF, LF, MF, and HF bands up through VHF, UHF, and microwave, catering to diverse applications including amateur radio, commercial installations, and military systems. Their product range includes mast-mount preamplifiers, inline attenuators, power dividers, and various coaxial components. My own experience with similar low-noise front ends for weak-signal work on 2 meters and 70 centimeters underscores the critical role such components play in maximizing receiver sensitivity, especially when chasing distant DX or engaging in EME. The detailed product descriptions and technical specifications provided on the site allow operators to select the optimal preamplifier for their specific band and noise figure requirements, essential for improving signal-to-noise ratio. The site also lists specialized products for unique applications like Nuclear Magnetic Resonance (NMR) and Studio Transmitter Links (STL), demonstrating a depth of engineering capability beyond typical amateur radio fare. This breadth of offerings, coupled with clear ordering and warranty information, positions Advanced Receiver Research as a key supplier for high-performance RF components.
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Antenna tuners are crucial for matching the impedance of antennas to the 50 ohm output impedance of transmitters. The _LDG Z-11 Pro_ is an automatic antenna tuner designed to handle up to 125 watts, making it suitable for a wide range of amateur radio applications. Its compact form factor allows it to pair well with transceivers like the _FT-857D_, providing a portable solution for operators who frequently change locations or setups. The tuner covers the 80 through 6 meter bands, offering a broad impedance match capability. Although it struggles with some loads, it performs well with typical ham antennas, even managing to load an 80 meter dipole on 6 meters. One of the standout features of the _Z-11 Pro_ is its 8000 memory slots, which enable it to remember successful matches and quickly retune when revisiting frequencies. This memory function significantly reduces tuning time, often to less than half a second. The unit is well-constructed, with improved pushbuttons and a sturdy metal case that offers good shielding. However, users should be aware of potential RFI issues and the lack of a power switch, which requires disconnecting the power cord to turn off the unit completely. Overall, the _LDG Z-11 Pro_ is a user-friendly and cost-effective tuner, offering advanced features that enhance its utility in various amateur radio setups.
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A 17 3/4-inch radiating element and 18 3/4-inch ground plane radials form the basis of this quarter-wave ground plane antenna for 2 meters FM. The design, attributed to AA1PG, utilizes a panel-mount SO-239 UHF connector and three lengths of #12 copper wire, with a total material cost estimated at $3.00. Construction involves soldering the elements directly to the SO-239, emphasizing thorough solder flow for robust connections. Recommended feedline includes _RG-8X_ for longer runs, with _RG-58_ acceptable for shorter lengths, cautioning against _RG-174_ for VHF applications due to high loss. The antenna is designed for elevated deployment, such as in trees or on roof gables, to maximize line-of-sight propagation. It aims to improve repeater access compared to typical rubber duck antennas, even with low power output.
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Operating the _Icom IC-746_ HF/VHF transceiver often presents specific technical questions, and this resource compiles a comprehensive Frequently Asked Questions (FAQ) document in an ASCII text format. It details common inquiries and solutions related to the rig's functionality, accessories, and potential modifications. The content is structured into distinct sections addressing general information, power supplies, antennas, microphones, keyers, amplifiers, TNC integration, and optional IF filters. The FAQ provides practical guidance on topics such as configuring the internal automatic antenna tuning unit (ATU), selecting appropriate power supplies, and understanding microphone pin-outs. It also delves into advanced subjects like computer control via CI-V, wiring for PSK31 operation, and troubleshooting common issues like low S-meter readings on 2m FM or loose tuning shafts. Specific questions cover the installation of optional IF filters, comparing Inrad versus Icom filters, and optimizing filter combinations for various modes. Furthermore, the document outlines various hardware and firmware modifications, including those for increasing monitor volume, replacing LCD driver transistors, and implementing a "poor man's TCXO." It even touches upon untested modifications, such as replacing PIN diodes in the demodulator. The FAQ also lists manual errata and discrepancies, offering a robust knowledge base for IC-746 owners seeking to optimize their station or resolve operational challenges.
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KB9AMG's Top WSPR Spots presents a focused online tool for monitoring **2-way WSPR reports**, specifically detailing propagation data from February 2026 through March 2026. This resource aggregates _WSPRnet_ data, allowing radio amateurs to observe weak signal propagation conditions across various bands. The interface is straightforward, presenting callsigns, frequencies, signal-to-noise ratios, and distances for each reported contact, which is crucial for understanding current band openings and signal paths. The utility of this WSPR spotter lies in its ability to quickly visualize global propagation. Users can identify active stations and assess signal viability over long distances, with reports often showing contacts spanning thousands of kilometers. For instance, a typical WSPR report might indicate a signal from Europe reaching North America with a _SNR_ of -25 dB, demonstrating effective low-power communication. This data is invaluable for planning DX operations or evaluating antenna performance under actual propagation conditions.
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A home made 50 MHz KW power amplifier project with picture and PCB schematic by W6PQL
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The 160-meter amateur radio band, spanning 1.8 to 2 MHz, was historically the lowest frequency amateur allocation until the introduction of the 630-meter and 2200-meter bands. ITU Region 1 allocates 1.81–2 MHz, while other regions use 1.8–2 MHz. This band, often called "Top Band" or "Gentleman's Band," was established by the International Radiotelegraph Conference in Washington, D.C., on October 4, 1927, with an initial allocation of 1.715–2 MHz. Effective operation on 160 meters presents significant challenges due to the large antenna sizes required; a quarter-wavelength monopole is over 130 feet, and horizontal dipoles need similar heights. Propagation is typically local during the day, but long-distance contacts are common at night, especially around sunrise and sunset, and during solar minimums. The band experienced a resurgence after the LORAN-A system was phased out in North America in December 1980, leading to the removal of power restrictions.
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A nice review of the Acom 1000 HF and 6 meter RFpower amplifier by Acom in Dutch and with online google translation available. Includes pictures and notes of the popular amplifier by Acom.
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The Boone Area Radio Klub (BARK) serves Boone County, Iowa, as its local amateur radio club, actively welcoming visitors to its meetings and weekly ARES nets. The club maintains a 2-meter repeater on 146.850/250 MHz with a 114.8 Hz tone and a 440 MHz repeater on 443.9+ MHz, both situated at the Boone County Hospital, with a simplex fallback on 146.550 MHz for the 2-meter net. Additionally, BARK supports the Iowa 160-meter ARES net at 1.972.5 MHz, which operates at 9:30 PM on Sundays, featuring a rotating schedule of net controls including KNØR, KBØMPL, NØISU, KEØQEU, and KBØLPI. BARK conducts bimonthly license testing sessions on the second Saturday of even-numbered months, with specific dates like October 19, 2024, at the Hamboree, requiring a $15 fee and prior FCC Registration Number (FRN) acquisition. The club's activities are well-documented through numerous photo galleries from past Field Days (1998, 1999, 2008, 2010, 2013, 2017, 2018, 2019), JOTA events (2013), and special event stations (2010 B&SVRR&M). Members like KBØMPL (Margot Conard) have contributed educational PowerPoint presentations on topics such as "Fun with Handie Talkies," "HF Propagation," and "Digital Mode - FLDIGI - OLIVIA 8/500 - JT65 HF - BAND PLANS." The club's officers, as of May 2018, include WØFS (Clay Conard) as President, NØISU (Mitch Carroll) as Vice-President, and KBØLPI (Eric Sloan) as Treasurer/Secretary, guiding the club's operations and community engagement.
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Low-frequency (LF) radio time signals, operating primarily in the 40–80 kHz range, are broadcast by national physics laboratories for precise clock synchronization. Transmitters like **JJY** (40 kHz, 50 kW; 60 kHz, 50 kW), RTZ (50 kHz, 10 kW ERP), MSF (60 kHz, 15 kW ERP), WWVB (60 kHz, 50 kW ERP), RBU (66.66 kHz, 10 kW), and DCF77 (77.5 kHz, 50 kW) cover vast geographic areas, often several hundred to thousands of kilometers. LF signals offer distinct propagation advantages over higher-band transmissions such as GPS. Their long wavelengths (3–6 km) enable effective diffraction around obstacles like mountains and buildings. The ionosphere and ground act as a waveguide, eliminating the need for line-of-sight and allowing a single powerful station to cover extensive regions. Ground wave propagation minimizes ionospheric variability effects on transmission delay, and signals penetrate most building walls effectively. Robust and low-cost receivers, often priced at 20–30 USD/EUR, are widely used in radio clocks. These receivers typically comprise a tuned ferrite core antenna, a receiver IC (e.g., Atmel T4227, U4223B, MAS1016) for amplification and AM detection, and a microcontroller for decoding the time signal and phase-locking a local clock. Specific components for DCF77, MSF, and WWVB are readily available from vendors like HKW Elektronik and Ultralink.
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Constructing a directional antenna for VHF operations, particularly for 2-meter band contests or local communication, often involves balancing performance with ease of build. The Moxon rectangle, a compact two-element beam, offers a good front-to-back ratio and gain in a smaller footprint compared to a Yagi, making it suitable for portable or temporary setups where space is limited. This design typically uses a driven element and a single reflector, bent into a rectangular shape to achieve its unique radiation pattern. The article details the construction of a 2-meter Moxon antenna, specifically for 144 MHz, utilizing readily available materials like PVC pipe for the frame and copper wire for the elements. It outlines the dimensions for the driven element at 970mm and the reflector at 910mm, with a spacing of 140mm between them, and a 50mm gap at the element ends. The feedpoint is a direct 50-ohm connection, simplifying matching requirements. The project includes a parts list, a basic diagram illustrating the element layout and dimensions, and photographs of the completed antenna. The author notes the antenna's performance during a QRP contest, achieving contacts up to 100km with 5 watts, demonstrating its effectiveness for low-power VHF work.
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Presents an interactive online **Moxon antenna designer** tool, enabling radio amateurs to configure and analyze lightweight Moxon antennas for HF and VHF bands. Users can specify design frequency, element lengths, wire diameter, insulation, and support height. The tool visualizes the antenna in interactive 3D graphics and generates comprehensive performance charts, including azimuth, elevation, 3D, and polarization radiation patterns, VSWR charts, antenna current diagrams, and Smith charts. It also allows selection of various ground types (e.g., very poor soil, salt water, free space) to model environmental effects on antenna performance. The designer provides insights into how physical dimensions and ground conditions influence key antenna parameters like forward gain, front-to-back ratio, and feed-point impedance, which is typically close to 50 ohms. It also includes a feature to model the effect of coaxial cable losses on **VSWR** at the transmitter end, distinguishing it from the feed-point VSWR. This helps operators understand the actual radiated power efficiency versus the apparent match at the transceiver, offering a practical perspective on antenna system performance in portable operations.
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Details the installation and operation of the DX Engineering TFS Series Transmit Four Square System Phasing Units, specifically models like the DXE-TFS4-160B, DXE-TFS4-80B, and DXE-TFS4-40B. It covers system components, required parts, and a discussion of vertical antenna selection, including a table of suitable DX Engineering Monoband Vertical Antennas. Installation procedures are outlined, encompassing site selection, four square layout, topographical considerations, and noise source mitigation. Specific instructions are provided for mounting the phasing unit, antenna feedline connections using 1/4-wave 75-ohm coaxial cables, and control wire routing. The document also includes details on radial system implementation, with a table of radial wire lengths for 160, 80, 75, and 40 meters, and procedures for tuning the vertical antennas for optimal performance. Operational aspects of the Four Square Control Console are described, including front and rear panel functions, control logic (Table 4), and typical transceiver/amplifier interconnections. The system enables directional control with approximately 5 dB gain over a single vertical element in four directions or an omni-directional pattern, achieving typical front-to-back ratios exceeding 20 dB. Lightning protection and initial system testing are also addressed, along with a 5 kW CW and 10 kW PEP SSB power rating and hot switching lockout feature.
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This tutorial demonstrates how to charge laptops or tablets, like the Microsoft Surface, using off-grid 12-volt batteries typically used for ham radio gear. The guide highlights the importance of selecting a reliable USB-C PD adapter, recommending a 15V, 60W minimum with 5–20V, 3–5A capability. Featured tools include a 100W USB-C adapter and a USB multimeter for monitoring power usage. The video also explores the compact, efficient Power Queen 50Ah LiFePO4 battery for portable power solutions.
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An Arduino-based interface provides a remote tuner call command for Icom **IC7700** and **IC7800** transceivers, addressing the lack of a built-in function for external tuners such as the MFJ 998RT. This setup initiates a low-power transmit signal, typically 15 watts, allowing the remote autotuner to perform its matching sequence. The article details the required CI-V line communication and modifications to existing Arduino code, specifically referencing contributions from Jean-Jacques ON7EQ for improved Icom interrogation routines. The system involves a sequence of steps: storing the transceiver's current mode and power, disabling the internal autotuner, activating a control relay to interrupt the amplifier line, switching to RTTY mode at low power, and initiating transmit. The transmit duration is manually controlled by the operator, observing the SWR meter until a low SWR is achieved, then a second button press stops the transmission. A built-in 4-second transmit limit provides a safety measure. After tuning, the routine restores the original mode and power settings, re-enables the internal autotuner, and performs a brief 2-second RTTY transmission for internal tuner adjustment. The circuit diagram includes a Panasonic form 2 relay for amp control and emphasizes critical delays in the Arduino code for stable operation at 9600 baud CI-V communication. Compatibility with logging software like DXLab, N1MM, and N3FJP is noted, with specific interrogation time settings required to avoid conflicts.