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Query: 100
Links: 473 | Categories: 13
Categories
- Radio Equipment > HF Amplifiers > Acom 1000
- Radio Equipment > VHF-UHF Mobile > ICOM IC-2100H
- Radio Equipment > HF Transceivers > Icom IC-7100
- Radio Equipment > HF Transceivers > Icom IC-9100
- Radio Equipment > Receivers > Icom IC-R7100
- Radio Equipment > Antenna Tuners > LDG Z-100
- Operating Modes > Satellites > QO-100
- Radio Equipment > HF Amplifiers > Yaesu FL-2100
- Radio Equipment > HF Transceivers > Yaesu FT-100
- Radio Equipment > HF Transceivers > Yaesu FT-1000MP
- Radio Equipment > Microphones > Yaesu MD-100
- Radio Equipment > Scanners > Radio Shack PRO-94
- Radio Equipment > HF Transceivers > Yaesu FT-891
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How to connect an Apple MacOS to a USB Radio transceiver. Get a Mac driver for ICOM IC-7100, IC-7200, IC-7300, IC-7600, IC-7610, IC-7850, IC-9100, PCR2500, Kenwood TS-890S, TS-990S, TS-590S, Elecraft KX3, K3S, Yaesu FTdx3000, FT-891, FT-991 or Ten-Tec Eagle USB direct connect built in USB/Serial adapter.
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The Icom IC-PW1 is a 1000 watt linear amplifier with built-in power supply
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A project by LY3H of a complete Scalar USB network analyzer with freeware windows software, sweep range 100 kHz to 160 MHz, powered by USB.
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The Delta Amateur Radio Club (DARC) serves as a community organization for amateur radio operators in the Memphis, Tennessee area, providing resources and activities centered around two-way radio communication. The club maintains the W4BS repeater system, which operates on 147.060 MHz with a +600 kHz offset and a 100 Hz PL tone, facilitating local VHF communications. DARC actively supports the Amateur Radio Emergency Service (ARES), preparing members for public service and disaster response through training and coordinated drills. The club also hosts regular meetings and events, fostering camaraderie and technical skill development among its members. Membership in the Delta Amateur Radio Club offers opportunities for participation in various amateur radio activities, including field day operations and local nets. The W4BS repeater provides reliable coverage across the Memphis metropolitan area, serving as a critical asset for both daily ragchewing and emergency traffic handling. DARC's affiliation with the Amateur Radio Relay League (ARRL) ensures access to national resources and advocacy, reinforcing the club's commitment to promoting amateur radio and public service within the community. The club's focus on emergency communications strengthens local preparedness.
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Building an End-Fed Half-Wave (EFHW) antenna from a kit, as detailed by Frank Bontenbal, PA2DKW, with process photos by Bob Inderbitzen, NQ1R, offers a practical approach for hams. This specific kit, a collaboration between ARRL and HF Kits, targets 10, 15, 20, and 40 meters, making it a versatile option for HF operations. Unlike a center-fed dipole, the EFHW is a half-wavelength antenna fed at one end, which simplifies deployment, particularly for portable use. The construction guide meticulously outlines the assembly of the 49:1 impedance matching network, crucial for transforming the antenna's high impedance (around 2,500 Ohms) to a transceiver-friendly 50 Ohms. Steps include preparing the enclosure by drilling holes for the coaxial connector and antenna connections, followed by the precise winding of enameled copper wire onto a toroid to create the transformer. The guide emphasizes careful insulation removal and soldering for reliable connections. Final assembly involves integrating a 100 pF capacitor for higher band compensation, soldering the transformer's primary and secondary sides, and conducting SWR tests with a 2K7 resistor or a half-wavelength wire. The document also provides examples of wire lengths for different bands, such as 16 feet for 10 meters or 66 feet for 40 meters, demonstrating the transformer's adaptability for various half-wavelength configurations.
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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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Over 100 FCC districts are analyzed by this resource, providing a predictive database for amateur radio vanity callsign assignments. The system simulates the FCC's application process, calculating the probability of assignment for specific callsigns, such as KD3Q at 94% or N9QC at 97.8%. Data is meticulously organized by FCC district, detailing available, pending, and upcoming callsigns, alongside those currently blocked by renewal or other FCC administrative actions. This allows hams to gauge their chances of securing a desired callsign. The database presents specific application entries, including the date entered, receipt date, process date, the applicant's current callsign, and the vanity callsigns they have applied for. Each entry facilitates examination of predicted outcomes, which categorize potential assignments as assigned, competitive, non-assigned, unneeded, curable, or unknown status. For instance, an application for K7DM clearly shows multiple applicants, indicating a highly competitive assignment scenario. This tool is particularly useful for those seeking a **short callsign** or a **1x2, 2x1, 2x2, 1x3, 2x3, 3x1, 3x2, or 3x3 callsign** that aligns with personal preferences or contest aspirations. It provides a clear, data-driven perspective on the likelihood of obtaining a specific vanity callsign.
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The MiniTioune receiver project, developed by Jean-Pierre F6DZP, consists of the home constructed MiniTiouner hardware which interfaces via a standard USB 2.0 port to a Windows PC running the MiniTioune software. It can be used to receive satellite broadcasts transmissions making it ideal for use on Q-oscar 100 Es hail-2 without any external frequency converters.
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Amateur radio operators in northwestern Wisconsin often seek local community and technical support, which the Barron County Amateur Radio Association (BCARA) provides. This organization facilitates regular meetings, nets, and events, connecting hams across the region for shared learning and operational experiences. Members engage in various aspects of the hobby, from contesting and DXing to emergency communications and technical projects, reinforcing local Elmering traditions. The BCARA maintains a presence on social media, including a Facebook group with over **100** members, enabling real-time communication and event coordination. The club also supports local public service events, demonstrating the practical utility of amateur radio. Their activities encompass both VHF/UHF operations and _HF bands_, ensuring a broad appeal to operators with diverse interests and equipment setups.
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A 10-meter half-wave vertical antenna, designed by Thomas 4L/G8BAG, offers a practical solution for hams with limited space and materials. This "flower pot" design utilizes common hardware store items such as 60mm plastic drain pipes and 75 Ohm coax cable, demonstrating that effective HF operation doesn't require specialized components. The author details the coax preparation, including stripping the outer sleeve and braid at specific measurements like **2510 mm** and 2450 mm, and integrating it into the pipe structure. The construction emphasizes simplicity and low cost, providing an accessible path to getting on the air on the 10m band, especially when a horizontal beam is not feasible. The article notes an SWR of _1.5:1_ with 75 Ohm coax, managed by an MFJ 258 for impedance matching. This temporary solution proved robust, withstanding various weather conditions and achieving contacts across continents, including W, VK, BG, G, JA, and VR2, using 100W SSB from Georgia.
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The loops are made of 10 mm round aluminum tube. No bending pliers was used to gently bend 90 degrees to obtain a square with 53 cm inner sides. Each loop has an impedance of approximately 100 Ohm. To connect both radiators in phase, a quarter wave long feeder of 100 Ohm is required.
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Operating as FY/F5UII, Christian F5UII conducted a DXpedition to French Guiana (FY) from January 13 to 30, 2013. The primary operation utilized the FY5KE radio club station in Kourou, with activity focused on voice modes during specific weekday hours. The resource details the operator's intent to transmit before 12:00z and after 22:00z, or as availability permitted, from the mainland. A significant aspect of this operation involved a dedicated weekend activation of the Salut Islands, specifically **IOTA SA-020**, from January 19-20, 2013. This segment of the DXpedition was conducted from Royal Island (Ile Royale), part of a group including Devil's Island (Ile du Diable) and St. Joseph Island (Ile Saint Joseph), located 14 km offshore from Kourou. The station setup for the IOTA activation included 100 Watts of power, a GPA-030 vertical antenna for 10m, 15m, and 20m, and dipole antennas for 17m and 40m, with antenna deployment contingent on site conditions and propagation. The operator anticipated strong interest for the SA-020 entity.
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The antenna I built was inspired by a portable delta loop designed by Doug DeMaw, W1FB. Given that I constrained myself to a 50-foot roll of speak wire, I scaled my antenna for the 20M band. Using the formula, 1005 divided by the frequency in megahertz, I calculated a total length of 71 feet (21.6 meters) for the center of the 20M band.
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Txtopia provides a browser-based Morse code translator that converts plain text to International Morse Code and decodes Morse back into text, supporting various Unicode dot and dash representations. The tool automatically detects translation direction, normalizes common input variations like middle dots (·), bullets (•), em dashes, and underscores, and explicitly flags unsupported characters or ambiguous sequences with visible placeholders rather than silently dropping them. It accepts spaces, tabs, newlines, and pipes as letter separators, and slashes or blank lines for word boundaries, recording collapsed separators for user review. Users can adjust playback speed from 5 to 40 WPM and tone frequency from 300 to 1000 Hz for CW practice, with playback adhering to international Morse timing. The application operates entirely client-side, ensuring user input remains in the browser without server transmission. It includes a comprehensive reference for the supported Morse alphabet, numbers, and punctuation, aiding in learning and verification. The tool is suitable for checking game clues, verifying tattoo designs, and transcribing messages for ham radio CW practice.
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Presents the construction and performance characteristics of the _Moxon Rectangle_ antenna, a compact, directional HF antenna design. It details the antenna's physical structure, emphasizing its robust build and ease of erection compared to traditional Yagis. The resource provides specific dimensions for building Moxons for the 10m through 40m bands, derived from _W4RNL_'s work, and discusses the critical element spacing for optimal performance. It also covers feeding the antenna with a simple choke balun and achieving a low SWR across the band. Compares the Moxon's performance to a two-element Yagi, noting its superior wind resistance and compact footprint. The author, _VK3BCY_, shares personal experiences with a 20m Moxon, reporting SWRs below 1.3 across the entire band and strong signal reports from DX stations with only 100 Watts. EZNEC Pro modeling data is included to illustrate gain and front-to-back ratios, confirming the antenna's high-performance claims. The article also briefly explores multi-band possibilities and reversible configurations.
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Just a simple signal generator based on ADF4351 module from fleebay allows you to generate one single frequency that can go up or down in 100Khz steps via two push buttons.
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ADIF-to-QSL-label is a GitHub utility designed to generate print-ready PDF QSL labels from ADIF log files. Optimized for the Avery Zweckform 3664 format (A4, 3×8 grid), the tool accommodates up to four QSOs per label. While an HTML version is suggested, the Python script provides extensive customization via the reportlab library. Users can precisely calibrate the layout through single-point configuration, adjusting page margins, global X/Y offsets, and specific column or row nudges. Key features include dynamic column sizing, support for any ADIF field (such as RST or Mode), and debugging tools that print outlines and guides for alignment testing. Configuration is managed via the script, YAML files, or CLI arguments, requiring "Actual size" (100%) printer settings for accuracy.
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Specification of the ICOM IC R7100, VHF UHF Receiver
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The video showcases the setup of a 300 MHz oscillator, a 100W radiofrequency amplifier, and a dipole antenna for transmitting radio waves, leading to the fluorescence of a nearby light bulb. It demonstrates the presence of standing waves on the dipole antenna and how intensity varies along its length. Additionally, the usage of a copper pipe as a receiving antenna is explored, showing changes in intensity depending on alignment and proximity to the transmitter. Finally, a B field antenna sensitive to magnetic fields is introduced, revealing brightness variations in different orientations. The video offers insightful observations on radio wave transmission and reception phenomena.
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The Icom IC-7700 spectrum scope feature a minimum resolution bandwidth of just 100 Hz and provide also an accurate vertical amplitude tracking permitting to use the 7700 as a bench spectrum analyser.
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An Excel sheet calculator for the T2FD wire antenna. The sheet has been proved to work either on LibreOffice and Apple Numbers. Just input the resonating frequency to get the proper size and dimensions.
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Examines current amateur radio satellite operations as of May 2026, providing a practical overview for hams interested in making their first satellite QSOs. The resource differentiates between Low Earth Orbit (LEO) satellites, such as the _ISS_, SO-50, RS-44, FO-29, AO-7, and GreenCube, and the geostationary QO-100. It highlights the distinct operational requirements for each, noting that LEO birds necessitate real-time tracking, antenna rotation, and Doppler compensation. The article emphasizes the critical practice of listening before transmitting and outlines methods for monitoring QO-100 in real time via the Goonhilly Earth Station WebSDR. It also covers tracking LEO satellites using tools like N2YO.com, Heavens-Above, and amsat.org/status. The author's experience with these platforms informs the guidance on equipment considerations and operating practices, ensuring hams understand the nuances of satellite communication in 2026, including the significant impact of QO-100 since its 2019 launch.
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A medium power End Fed Half Wave Antenna coupler, specifically tuned to the QRP frequency of 7030 kHz. Constructed from coil stock and capacitors, it achieves an impedance ratio of 64:1. The coupler has proven effective for power ranges from 2 to 100 Watts on the 40m band.
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SMSS - Swedish Lakes. A Contest where you collect as many lakes as possible of over 100000 lakes.
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Presents an interactive **Ham Bands Explorer** web application, offering a live view of all amateur radio bands overlaid on a world map. This resource displays **CQ zones** and **ITU zones**, with geographical data sourced from HB9HIL/hamradio-zones-geojson under an MIT license. The interface provides a dynamic visualization of global band conditions, enabling operators to observe activity patterns across different regions. Users can select individual countries to retrieve and display their specific band plans, with frequency coverage details loaded from CountryData.json. The tool indicates 100% frequency coverage, ensuring comprehensive data presentation for selected regions. This functionality supports detailed analysis of national regulatory variations within the amateur spectrum. The application integrates both a map view and a live view, facilitating real-time monitoring and geographical context for band usage. It serves as a practical reference for understanding international amateur radio regulations and visualizing propagation characteristics across various frequency allocations.
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How to solve the problems with the ICOM IC R7100 receiver that every time the squelch opens or closes, it produces a clicking noise.
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This utility program shows the impedance and reflection coefficient parameters (SWR, reflection coefficient magnitude Rho, or Return Loss RL in dB) at both ends of a transmission line and the details of power loss in the line. It includes built-in specifications for approximately 100 different line types. You can modify the specs to see how small changes affect the results or to specify custom lines. All program inputs may be changed directly or you can use spin buttons to make the changes.
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Presents two distinct hardware modifications for the Icom IC-7300 transceiver, detailing the necessary steps for each. The first modification, a _MARS_ transmit expansion, involves the physical removal of specific surface-mount diodes (D422) from the main board, enabling transmit capabilities across a broader frequency range, including out-of-band frequencies. It specifies the diode location on US versions of the IC-7300 and suggests using small diagonal cutters if a soldering iron is not preferred or available. The second modification focuses on the internal antenna tuner, aiming to provide wider impedance matching capabilities. This involves adding a **100k ohm** resistor to a designated point within the tuner circuit. The resource also briefly mentions a microphone modification for the _HM219_ and a general power increase, though without specific instructions for the latter two. It emphasizes safety precautions, such as disconnecting power and inspecting the work area.
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Modification to an old cellular phone base station modules, with a fairly reduced output power (10 watts or so), the stock power amplifier modules will cover the 2.3 GHz and 2.4 GHz amateur radio bands.
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A review of the most popular and traditional methods to learn morse conde and a different method that foreseen to learn 100 most common words in CW
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Author is currently developing the HS4HF 4 Band HF Radio Transceiver with a 5.0-inch TFT display, following their previous HSM1 model. They are also working on the Radio HSDRA, an All Band SDR HF Radio Transceiver with unique features such as DSP Digital Modulation, 100W final power, automatic antenna tuner, and more. The development includes a wide 5.0-inch display, touch screen, and various advanced functionalities. Stay updated with the latest developments in the world of HAM radio with Hambuilder Team.
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Repairing an Anritsu MS2711A handheld spectrum analyzer
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Practice these operating techniques so you will be ready to capture that 100-point bonus on Field Day. QST Article
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The "Beginner’s Guide to Small-station EME" by Paul Bock, K4MSG, offers an insightful look into Earth-Moon-Earth communication, a fascinating aspect of VHF and above amateur radio. This presentation demystifies moonbounce, explaining how two-way radio contacts are made by reflecting signals off the Moon. K4MSG highlights the historical context of EME, noting the substantial investment and technical challenges that once characterized these operations, often requiring setups like the W5UN "Mighty Big Array" (MBA). Historically, path loss exceeding 250 dB, spatial polarization offset, Faraday rotation, and galactic noise made EME a formidable pursuit, with CW being the mode of choice for signals that had to be audibly detectable. Equipment limitations in noise figure and coax performance further compounded the difficulty for early moonbouncers. However, the landscape of amateur EME dramatically shifted around 2003 with the introduction of the JT65 software. This innovation, specifically designed for EME, allowed for signal decoding well below the noise floor, making small-station EME a practical reality for more hams using common transceivers and less complex antenna systems.
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Approximately 100 MeshCom nodes are visualized in real-time on a geographical map, providing a dynamic overview of the LoRa mesh network. This resource, hosted by _OE1KFR_, details node positions, telemetry data, and message traffic. Users can measure distances between two selected nodes, view text messages with callsign, destination, and gateway information, and access position data including latitude, longitude, and altitude. The platform supports filtering by regions such as Europe, USA, and Asia, allowing operators to focus on specific geographical areas. The detailed node list table presents comprehensive status information for each node, including gateway callsign, firmware version, hardware type, and environmental telemetry like temperature, pressure, humidity, and CO2 levels. This granular data enables operators to monitor network health and individual node performance, facilitating troubleshooting and optimization of MeshCom deployments. The map interface enhances situational awareness for those engaged in LoRa mesh networking.
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The Shiawassee Amateur Radio Association (SARA), operating under the call sign W8QQQ, serves as a non-profit amateur radio organization in lower central Michigan's Shiawassee County. Its primary objectives include public service, emergency communications, and advancing amateur radio through education and technical excellence. The club maintains a weekly _Skywarn_ 2m net on the N8VDH repeater at 147.02 MHz (+.6 MHz, 100 Hz tone) every Monday at 7:00 PM, actively seeking more local hams to participate. SARA also facilitates VE testing, with upcoming sessions like the one scheduled for April 23, 2026, at 6:30 P.M., requiring pre-registration by April 20. SARA holds monthly meetings at the James P. Capitan Building in Corunna, typically on the second Tuesday of each month at 7:00 PM local time, excluding December's social event. They offer Zoom meeting options for members unable to attend in person. Annual dues are $15.00, with a reduced rate for new licensees, making it a very low-cost club. The organization actively seeks more EMCOMM assistance from all Shiawassee County hams, not just club members, to bolster their ARPSC (ARES/RACES) capabilities, noting that only about **10** out of **200+** county hams are currently active in ARES. They also maintain a Google Group, "W8QQQ," for electronic notifications and club communications.
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The U01 emergency communications antenna is a versatile, multiband antenna designed for 80/60/40/20/17/15/10m bands, known for its reliability and compact size. It features a broadband transformer wound on various core options like FT82-43, FT114-43, or FT140-43, with the latter capable of handling up to 100W. The antenna incorporates a PCB with options for SMA and BNC connectors, and a weather-proofed design for durability. The lightweight construction, using materials like DX Wire UL and Polyester rope, makes it highly portable. The antenna's design has been tested and proven within the DARC Chapter U01, with multiple build options and detailed documentation available for DIY enthusiasts.
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Demonstrates the construction of an **ATU-100 (N7DDC)** automatic antenna tuner, detailing the assembly process from component arrival to final enclosure. The resource covers winding the tandem match transformer, connecting the OLED display, and integrating optional control buttons. Specific attention is given to modifying the EEPROM settings for **QRP operation**, reducing the minimum tuning power to 1 Watt, and addressing potential RF interference with CPU by adding capacitors to button connections. The build log includes practical tips such as adapting RG58 coaxial cable strands for PCB mounting and utilizing a repurposed Macbook Pro cover for the custom enclosure. The author references external GitHub pages for comprehensive information, R0AEK's resources for additional details, and a video by MW0SAW for EEPROM configuration across different ATU-100 variants. Future plans involve field testing the completed tuner during SOTA or other portable activations.
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The RM Italy HLA 300 linear HF amplifier, a solid-state unit designed for 12-14 V operation, is examined through practical experiences and test results. This survey highlights key operational aspects, including the necessity of the ventilated 'V' version for effective cooling, which operates quietly on standby and engages immediately on transmit. Manufacturer specifications claim 300 W CW output with 1-15 W input and 550 W SSB output with 2-20 W input, making it a robust option for many HF operators. PH4U/DC2DC's field tests on his HLA 300, an all-band/all-mode transistor amplifier drawing 45 A, provided valuable insights into its real-world performance. The amplifier features six low-pass filters, covering nine HF bands, a notable inclusion compared to many similar products. Testing revealed that a 1-Volt drop in the 12-14V supply, common with high currents (45-55 Amps) and inadequate cabling, can significantly impact output power, with a 50 W increase observed when voltage rose from 12 V to 13 V under load. Observations also noted that driving the HLA 300 with only 5 W, such as from an FT-817, is insufficient to reach its full potential, suggesting an intermediate amplifier stage is needed to achieve the recommended 20 W input. Modifications, such as removing a 100 pF capacitor, improved performance, and replacing output transformers with BN43-7051 (mix 43) ferrites significantly reduced distortion, as evidenced by spectrum analyzer images from PA1HR's HLA 150 modification.
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Details the history and evolution of **Continuous Wave (CW)** radiotelegraphy, tracing its origins from 1800s railroad telegraphy using Samuel F.B. Morse's electrical code pulses to its exclusive use with spark-gap transmitters in early radio. Explains how vacuum tube oscillators enabled pure, efficient CW signals, forming the backbone for modern digital communication modes. The resource emphasizes that Morse code remains relevant in amateur radio, valued for its ability to penetrate adverse atmospheric conditions and its role in QRP operations. It outlines effective Morse code learning methodologies, specifically endorsing the **Koch** and **Farnsworth** methods, which prioritize learning by sound at higher character speeds (e.g., 20 WPM) with extended inter-character spacing (e.g., 5 WPM). The content stresses the importance of mastering individual characters with 90% accuracy before progressing. It also provides an extensive overview of CW key types, including the Straight Key, Side-Swiper (Cootie), Semi-Automatic Key (Bug), Dual-Lever Paddle (Iambic), and Single-Lever Paddle, detailing their operational characteristics, typical sending speeds (e.g., 20-100+ WPM), and construction considerations. Furthermore, the page presents several homebrew projects, such as a $10 Cootie key, an ultra-simple code oscillator, an Arduino-based CW decoder capable of 70 WPM, and a 4-stage CW audio filter. It also highlights QRP rig builds like the SW+40 and portable setups for POTA/SOTA, and lists prominent CW clubs like the Straight Key Century Club (SKCC) and the American QRP CW Club (NAQCC).
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Exploring digital radio modes, the author rethinks how to adjust transmit and receive levels in WSJT-X. Despite effective communication using Yaesu's settings, a new procedure aims for better performance. For RX, set audio device levels to 100%, disable AGC, and adjust RF gain. For TX, enable "Remember power settings" and adjust power output to avoid ALC engagement. This method ensures reliable communication without signal degradation, enhancing dynamic range and minimizing noise.
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This PA has been designed by Sergey EX8MLE and uses three Mitsubishi RD100HHF1 FETs, Frequency Range 70 to 72 MHz
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Adjust date and time of your Icom transceiver from a Windows PC. Compatible with IC-705, IC-7100, IC-7300, IC-7610, IC-7600, IC-7851 (7850), and, IC-9700
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This project outlines the construction of a simple TEFV (Tilted End-Fed Vertical) antenna suitable for backyard or park installations. The design requires basic materials such as 100 feet of coated stranded copper wire, wood stakes, metal ground rods, a non-conductive fiberglass pole, and essential tools like wire cutters and a soldering iron. The antenna is supported by a 20-33 feet tall pole and includes a 9:1 unun for impedance matching and a resistor for tuning. Step-by-step instructions guide the assembly, from preparing the wire and pole to connecting the unun and resistor, ensuring a functional and durable setup for outdoor use.
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A transmitting antenna 2x15m, about 100 foot doublet antenna fed by a ladder line of about 600 Ohm. Article in Polish and English,
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Exploring LoRaWAN Range, comparing the performance of 1Watt and 100mW LoRa trackers on daily commute. Analyzing APRS tracks, beacon statistics, and visual comparisons to uncover insights and surprises in the world of long-range wireless communication.
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EA4EOZ details the construction and testing of 50 MHz traps, a critical component for multiband antenna designs. The project addresses the challenge of sourcing high-voltage capacitors suitable for trap applications, exploring alternatives to expensive doorknob capacitors. The author successfully fabricated a capacitor using 1.6mm double-sided FR-4 PCB material, achieving a capacitance density of **2.6 pF/cm2**. Utilizing the _VE6YP calculator_, specific L and C values of 30 pF and 0.31 uH were determined for a 2cm diameter coil. Both the FR-4 PCB trap and a coaxial cable trap, constructed from _RG-58_, were built and tuned to approximately 50 MHz using a spectrum analyzer. The coaxial cable trap demonstrated superior performance, exhibiting a notch nearly **20dB deeper** than the FR-4 version. This practical comparison provides insights into trap construction for experimental antennas, with the coaxial cable trap selected for an antenna project intended for operation at up to 100 watts.
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The 222 MHz Transverter project, based on Zack Lau's (W1VT) original July 1993 QEX magazine design, provides an IF of 28 MHz for both transmit and receive paths. Rick Bandla (VE3CVG) contributed supplemental notes and construction details, including modifications to achieve 10 mW output power from an initial 4 mW PEP. The design incorporates three distinct boards: a Local Oscillator (LO), a Transmitter (Tx), and a Receiver (Rx), with an estimated parts cost of just over $150 CDN, significantly less than commercial kits. Construction involves both through-hole and surface-mount components, with specific guidance on mounting MAV and MAR devices, grounding techniques, and component selection. The project details include parts lists, schematics for the LO, Tx, and Rx, and board layouts. Troubleshooting advice emphasizes sequential testing, starting with the LO, then Tx, and finally Rx, using a 194 MHz and 222.100 MHz capable FM handheld for signal tracing. Further enhancements are discussed, such as an optional Tx driver stage to boost output to 100 mW and the potential modification of a Motorola Maxor 80 PA for 222 MHz SSB/CW operation. The resource also covers practical aspects like power attenuation pads for IF radios (e.g., FT817) and considerations for enclosure design, including repurposing a Maxor 80 case. Performance reports indicate successful 70 km contacts with only 4 mW output.
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The *SPACE* Amateur Radio over Internet Protocol (RoIP) system offers public audio transmissions from NASA Mission Control and astronauts, primarily for educational purposes. This service streams NASA public media sources, including *Artemis II* and the ISS public audio channel 2 feed, which predominantly features English communications. Astronaut activities on the ISS typically occur between 0700 UTC and 19:00 UTC, with transmissions most common during early mornings USA time, alongside special events such as launches or spacewalks. Users can connect to the live stream via EchoLink to the *SPACE* conference, via IRLP to the 0100 experimental reflector, or via Allstar to node 516221. EchoLink connections utilize the GSM CODEC, while IRLP and other connections default to uncompressed or u-law CODEC. The service notes that long periods of silence are common, and NASA audio sources can be periodically unavailable or noisy. Daily recordings of these transmissions are published at space.rfnet.link/recordings/, available as .ogg audio files for direct playback or .m3u8 playlist files for network streaming in applications like VLC. Each playlist file provides a list of timestamped audio transmissions, allowing users to review specific segments of interest.
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100 Watts and a Wire is a ham radio talk show was originally launched as an audio podcast on June 22, 2015. Today, you can see the show on YouTube. It features topical conversation, interviews and ham radio news. You can listen anytime by subscribing wherever you get podcasts.