Search results

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.

The Acom 1500 HF+6M Linear Amplifier is a high-quality and user-friendly amplifier that provides excellent performance and reliability. G6NHU, who previously owned an Acom 1000, upgraded to the Acom 1500 after nine years and has been using it for about eighteen months. Key features highlighted include the ability to connect three antennas internally, straightforward tuning process, robust construction that can handle high SWR, quiet operation, fast and quiet switching for efficient CW operation, and clean output signal even when driven hard. G6NHU highly recommends the Acom 1500 and states they would not hesitate to purchase another one in the future.

The QubeDX is a modular CubeSat-style QRP transceiver designed for digital mode operation with remote Wi-Fi control via VNC. This project integrates a QRPLabs QDX 5W transceiver, an ATU-100 antenna tuner, and a Raspberry Pi 5 in a custom 14x14x14cm 3D-printed enclosure inspired by CubeSat design. Prioritizing affordability and functionality, the system operates on a single 13.8V power supply and includes auto-tuning and software like WSJT-X. With a total cost of under €250, it offers a decorative and portable ham radio solution.

Repair of a Yaesu FT-1000 MP Mark V probably struck by lightning.

This project involved designing a 7-pole Chebychev broadcast band filter to address severe interference issues caused by a new horizontal loop antenna on the KN-Q7A transceiver. The interference overwhelmed the transceiver’s front end, so a custom filter with a 3.5 MHz cutoff was built using silver mica capacitors and type 6 T130 toroidal cores. Encased in a diecast box with SO239 sockets, the filter blocks strong signals from the broadcast band, achieving over 100 dB attenuation. Tested up to 100W, it reduces interference effectively while maintaining low insertion loss across HF bands.

This article details the design and construction of a compact 20-meter QRP SSB transceiver by Pete Juliano, N6QW, measuring just 2 x 4 x 2 inches—small enough for a shirt pocket. Inspired by a 1963 QST design and refined from a prior version, it employs bilateral circuits, a 4.9152 MHz homebrew crystal filter, switched-crystal VXO for 60 kHz coverage (14.160-14.220 MHz), and standard components like ADE-1L mixers and IRF510 PA for 1W output. Key innovations include a double-sided PCB skeletal frame for shielding and isolation, Vectorboard sub-assemblies, and ultra-miniature relays. The bilateral receiver/transmitter shares stages, omitting AGC for simplicity, while a W3NQN LPF and optional 10W external amp enable DX contacts. Tune-up focuses on crystal matching and bias for linearity. Videos on YouTube demonstrate performance, confirming excellent stability and audio. Total cost nears $100, prioritizing portability over features like CW.

The article by Guy Olinger, K2AV, published in the May/June 2012 National Contest Journal, introduces the Folded Counterpoise (FCP), a compact 516-foot single-wire counterpoise elevated at 8 feet, designed for 160-meter operations on small lots like 100x150-foot backyards. Originating from efforts to revive Top Band for W0UCE on a postage-stamp property, the FCP uses strategic folds to cancel ground fields within 33 feet of center, minimizing losses to 0.13-0.53 dB—outperforming sparse or on-ground radials by up to 15 dB in poor soil—while mimicking opposed radials for efficient feedpoint impedance. Paired with a critical 1:1 or 4:1 isolation transformer (e.g., trifilar on T300-2 toroid) to block common-mode currents on coax feeds, it delivers proven results: K2AV's #8 North America low-power contest score, 7+ dB gains at W4KAZ and K5AF, and over 10,000 global web hits for DIY instructions using bare 12 AWG wire and weatherproof enclosures. Ideal for acreage-challenged hams, the FCP also excels on 80 meters with scaled dimensions, offering a low-loss alternative where full radials are impractical

Detailing a Yaesu FT-857 and ATAS-120 installation in a 1997 Toyota Tacoma, the author used Polar Plot to map signal strength. Using a hand truck with a laptop, FT-817, and an Iron Horse antenna, they circled a chalk-outlined 100-foot diameter, revealing potential nulls towards the truck's rear and through the cab, offering insights into antenna performance.

This article examines how geomagnetic activity influences 160-meter radio propagation. K9LA analyzes observations of enhanced signals preceding K-index increases. Modeling shows that as ionospheric electric fields rise from 0 to 75 mV/meter during early geomagnetic storms, they create an electron density valley above the E region, enabling signal "ducting" between the E and F regions. This effect vanishes at higher field strengths (100 mV/meter). The phenomenon may explain both exceptional 160m openings preceding 6m propagation and possibly Marconi's contested 1901 transatlantic reception, which occurred during a small geomagnetic disturbance.

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.

The _MFJ-915_ RF Isolator, rated for 1.8-30 MHz and 1500W PEP, exemplifies the product range available from The Ham Shop. The inventory includes various antenna support ropes, such as 3/16" _Dacron Polyester Rope_ in lengths from 100 to 1500 feet, alongside a selection of cables for _SignaLink USB_ sound card interfaces. Specific SignaLink cables are offered for radios like the Yaesu FT-847 (SLCAB847), Yaesu HTs (SLCABVXY), and the Elecraft K3 (SLCABHTY). Additionally, the shop provides modular jumper cables and modules, including the SLMOD8RY for Kenwood/Alinco 8-pin round mic jacks and the SLMOD8RI for Icom 8-pin round mic jacks. The product line supports diverse station configurations, encompassing antennas, coax, baluns, dummy loads, duplexers, insulators, microphones, power supplies, SWR meters, and watt meters.

Manually programming a Yaesu FTM-100 with hundreds of channels can be very fustrating. In this article the author highlights the difficulty of entering data with small buttons and the need to look up information for each channel. To avoid this tedious process author used RT Systems software as a solution. This program simplifies programming by allowing selection based on the radio model, download of frequencies from resources like RFinder, and quick loading onto the radio. While paid unlike the free CHIRP software used previously, the author emphasizes the time saved compared to manual entry, making the cost worthwhile.

YaesuFT1000MK V stands out with improved close-spaced SSB transmit performance, reversing a trend seen in other modern radios. Featuring a class-A mode, it offers clean HV finals when kept out of ALC. However, two significant flaws persist: the noise blanker causes receiver IM distortion, and the transmitter lacks wave-shaping on CW, resulting in pronounced keyclicks. Preliminary tests reveal strong keyclicks +1kHz and -1kHz, prompting a combined modification to address both issues.

The TY0RU DXpedition to Benin in 2022 achieved over **100,000 QSOs** from Cotonou, IOTA AF-051, operating across 160m through 6m bands using CW, SSB, and FT8 modes. The operation involved a team of 12 operators, including _F5RAV_, _F4WBN_, and _F1TCV_, utilizing multiple stations with transceivers like the Icom IC-7300 and IC-7610, paired with amplifiers and various antennas such as verticals, dipoles, and a 4-square array for 40m. The expedition's log is available on Club Log, supporting OQRS for both direct and bureau QSLs, with F5RAV serving as the QSL manager. The site details the team's travel, setup, and operational challenges, including local conditions and equipment deployment, offering insights into the logistical complexities of activating a rare DXCC entity. Donors are acknowledged, and a photo gallery documents the activity.

The N7YG Digital Engine, functions as a streamlined digital modem, supporting **PSK**, **RTTY**, and **MFSK** modes. It eliminates many ancillary logging and awards features found in other software, focusing instead on providing a dedicated digital interface. The software is specifically engineered to complement the N3FJP logging suite, offering a simple digital modem with a floating waterfall display that can coexist on the same screen as the logger. The application includes support for PSK Reporter, EXTFSK, TinyFSK, and K1EL Winkey FSK, enhancing its utility for various digital operations. Key features comprise a separate waterfall window, a main GUI with operational controls, receive and transmit display areas, and 10 Macro Buttons across 10 user-definable macro banks, totaling 100 macros for general and contesting use. Configuration options include sound card selection, digital gain (0-32767), AFC Level (0-100), AFC Width (in Hz), and COM Port TX keying for VOX/SignaLink or direct port control. Input and Output Mixer buttons provide direct access to OS audio mixer controls for precise level adjustments. The software is digitally signed with a security certificate, aiming to prevent conflicts with antivirus programs.

VE1ZAC's analysis details the performance of **MFJ927** and **SGC239** autotuners with portable HF vertical antennas, specifically comparing 31 ft and 43 ft configurations. The resource originated from challenges encountered during a Maritime QSO Party roving operation, necessitating a lightweight and easily deployable antenna system. Target bands for the contest included 80, 40, 20, 15, and 10 meters, with a maximum power handling of 100 W CW. The author utilized a 30-foot carbon fiber push-up pole to support a vertical wire element, noting its 2 lb weight and reliability. EZNEC modeling was employed to predict performance, showing favorable results for a 30-foot vertical with elevated radials, particularly on 40 and 20 meters. Feedpoint impedance measurements, taken with an AIM4170C, are presented for various HF bands, both with and without a 41-foot RG6 stub designed to reduce reactance on 80 and 20 meters. The stub significantly improved matching on these bands, easing the tuner's workload. Operational tests revealed issues with the MFJ927's reliability during contest setup, leading to reliance on the K3's internal tuner. The SGC239, tested post-contest, performed flawlessly. A detailed side-by-side comparison covers mechanical aspects, connection options, power bias, impedance range, board quality, and documentation. Modifications to the MFJ927, including a new aluminum case, white paint for heat reduction, and upgraded impedance-measuring resistors, are also described.

The LKJ Wednesday Night Special Antenna, designed by John Whiteman K5LKJ, is a compact 50-foot coil-loaded dipole for 80-meter operation, ideal for space-limited hams in residential areas. Using two 1-inch diameter PVC coils with 87 turns of #16 magnet wire each—placed 10 feet from the center—it tunes to 3.910 MHz for local nets like BVARC Rag Chew. Constructed with #14 wire, ceramic insulators, and Mini-8X feedline, it handles 1000W, performs well at low heights for NVIS, and requires a tuner for bandwidth. Collaborative tuning by club members ensured success.

A full-wave delta loop antenna, approximately 141 feet in total wire length for the 40-meter band, offers a low angle of radiation, which is highly advantageous for DX operations. This design, optimized for both 30m and 40m, leverages a specific circumference calculation of 1005/F, ensuring resonance on both bands through a simple switching mechanism. The antenna's configuration enhances long-distance communication, making it a practical choice for hams with limited space. The resource details the construction process, including the use of a _Ceramic Knife Switch_ for band selection and an _RG-11_ matching section to achieve optimal impedance. It outlines the precise loop lengths required for each band, along with tuning secrets to ensure efficient operation. Requiring a minimum height of 12 feet, this antenna can be supported by a single mast or tree limb, making it suitable for suburban installations where stealth or space constraints are a factor.

A dual insert microphone design for the Icom IC-7300 transceiver utilizes a **Besson BZ2400 M4 Rocking Armature** insert for frequencies from 500 Hz to 3 kHz, exhibiting a rising response of approximately 11 dB. A generic Electret Condenser insert, powered by the transceiver's microphone line, covers the low-frequency range from 100 Hz to 500 Hz. A Low Pass Filter is incorporated after the Electret insert to prevent frequency overlap, and a pre-set potentiometer (VR1) adjusts the low-frequency response, balancing the output of both inserts. The design emphasizes a "Close Talking" arrangement and addresses audio "colorization" by housing the Besson insert in a thick rubber holder with a foam boot, separate from the circuitry, with the Electret insert also wrapped in a foam boot. Critical importance is placed on using the correct BZ2400 M4 insert with 12 holes in its face plate. The frequency response table for the BZ2400 M4 insert shows 0 dB at 500 Hz, rising to +11 dB at 3000 Hz, while the Electret insert with the Low Pass Filter provides 0 dB at 100 Hz, rolling off to -9 dB at 500 Hz and -50 dB at 3000 Hz. This combination ensures a broad, balanced audio spectrum for SSB operation. The project includes a circuit diagram, a comprehensive parts list detailing components like a 1 Henry iron-cored inductor (L1) and various capacitors, and a board layout within the metal tube. The completed unit provides a tailored audio profile for the IC-7300, enhancing transmit audio quality.

The Olivia digital mode, a **Multi-Frequency Shift Keying (MFSK)** radioteletype protocol, is specifically engineered for robust communication under difficult propagation conditions on shortwave radio bands from 3 MHz to 30 MHz. Developed by Pawel Jalocha in 2003, Olivia signals can be decoded even when the noise amplitude exceeds the digital signal by over ten times, making it highly effective for transmitting ASCII characters across noisy channels with significant fading and propagation phasing. Early on-the-air tests by Fred OH/DK4ZC and Les VK2DSG on the Europe-Australia 20-meter path demonstrated intercontinental contacts with as little as one-watt RF power under favorable conditions. Common Olivia modes are designated as X/Y, where X represents the number of tones and Y is the bandwidth in Hertz, with examples including 8/250, 16/500, and 32/1000. The resource clarifies that Olivia, unlike some other digital modes, produces a constant envelope, allowing RF power amplifiers to achieve greater conversion efficiencies and making it less prone to non-linearity. Operators are advised that **Automatic Level Control (ALC)** can be set higher than no meter movement for MFSK modulation, as long as it's not driven past its high limit, contrary to common misinformation about other digital modes. The Olivia community encourages voluntary channelization on suggested calling frequencies, such as 14.0725 MHz for 8/250, to facilitate initial contacts, especially for signals below the noise floor. The Olivia Digital DXers Club provides links to Groups.io, Facebook, and Discord for community engagement and offers details on QSO parties.

Twenty 1-watt carbon film resistors are configured in parallel to construct a 50-ohm **dummy load** for amateur radio applications. The design incorporates a heatsink for thermal dissipation and an **SO-239 connector** for RF input, making it suitable for QRP operations. This budget-friendly project details component selection, soldering techniques, and mounting procedures, achieving a continuous power rating of 10 watts and intermittent handling of up to 100 watts across HF and VHF frequency ranges. The resource provides a step-by-step guide for assembly. This construction offers an economical solution for essential shack tasks such as antenna tuning, transmitter testing, and SWR meter calibration without radiating an RF signal. The utilization of readily available components significantly reduces the overall build cost compared to commercial alternatives, providing radio amateurs with a functional and reliable test accessory. While specific VSWR measurements are not provided, the design prioritizes practical utility for low-power transceiver diagnostics and general RF experimentation.

Dates: Arrival: January 6th , Departure : January 21th 2023 Call sign: TN8K Operators - Petr OK1BOA, Petr OK1FCJ, Palo OK1CRM, Pavel OK1GK , Ruda OK2ZA, Ludek OK2ZC, Karel OK2ZI, David OK6DJ Bands: 160-6m + QO-100

This project describes a high-performance EME antenna array consisting of two home-designed 9-element Yagis, each about 2.5 wavelengths long, combined into a 25-ohm system and matched to 100 ohms using 9/4λ sections of 50-ohm coax. The array supports rotatable polarity from 0° to 180°, allowing both horizontal and vertical polarization to optimize moonbounce performance under varying conditions. Despite operating for years without a balun—something another designer called “disastrous”—the system has delivered strong results, including copying very weak DX such as VK3KH at about -25 dB with only 120 W (around 2 kW ERP). The builder continues to refine the mechanics, having installed new gear motors and an upgraded follow-up control system in 2011.

A homemade oak plank drive-on mast holder proved functional but heavy and cumbersome. A lighter, compact commercial version from Amazon seemed ideal but couldn't fit the preferred Jackite pole. Costly alternatives, like a $100 mast holder from Three Mosquitoes Gear, were impractical. The solution came through DIY ingenuity: a piece of 2" PVC and hose clamps, repurposing materials already on hand. This simple, effective design perfectly accommodated the Jackite pole, demonstrating the power of resourceful problem-solving.

Details the construction and performance of a phase-controlled receiving array, specifically a **MicroSWA** variant, optimized for QRP low band fox hunting on 40M and 80M. The resource documents the author's iterative design process, addressing significant regional noise challenges encountered during 0100-0230 UTC fox hunt periods. Initial experiments involved a director wire on a 40M vertical, yielding limited improvement, prompting a shift towards advanced null-steering techniques. The project leverages concepts from Victor Misek’s "The Beverage Antenna Handbook" and Dallas Lankford’s extensive work on phased receiving antennas for urban lots. A key modification involved integrating a new passive phase control box and a push-pull **Norton common base preamp** using 2N5109 transistors, designed for high third-order intercept performance to maintain weak signal integrity amidst strong adjacent signals. The system incorporates Faraday-shielded transformers with RG174 primaries on -75 ferrite cores, housed in ABS plastic pipe. Performance tests confirmed the MicroSWA's ability to produce deep, steerable nulls, achieving approximately 30 dB noise reduction on 160M, 80M, and 40M. This enabled detection of QRP signals undetectable on conventional transmit antennas. The final unit includes front panel controls, a 10-11 dB preamp, and a robust power conditioner, demonstrating effective noise mitigation for challenging low band QRP operations.

Assessing the ICOM IC-R9000 communications receiver, this review details its operational parameters and user experience for radio enthusiasts. Introduced in 1985, the IC-R9000 covers a broad frequency spectrum from 0.1 MHz to 1999.8 MHz, making it suitable for a wide array of listening activities from medium wave (MW) to VHF/UHF. Key performance metrics include a dynamic range of **102 dB** with the narrow SSB filter, crucial for discerning weak signals in crowded bands, and its substantial physical dimensions of 424 x 150 x 365 mm and 20 kg weight. The receiver's architecture supports various modes, though it notably lacks synchronous detection, a feature often desired for improved AM reception under fading conditions. It incorporates 1000 memory channels and robust scanning capabilities, facilitating efficient monitoring across its extensive frequency range. This analysis provides insights into the IC-R9000's capabilities and limitations, offering a historical perspective on a significant piece of amateur radio and shortwave listening hardware.

The **Yaesu FRG-100** shortwave receiver, introduced in 1992, operates across a frequency range of 50 kHz to 30 MHz, accommodating AM, LSB, USB, and CW modes, with an optional narrow-band FM capability. Its physical dimensions are 238 x 93 x 243 mm, with a weight of 3 kg, making it suitable for both portable and fixed station deployments. Power options include standard mains voltage or 12VDC, providing operational flexibility for diverse listening environments. The front panel integrates a manual tuning knob, an analogue signal strength meter, and an LCD display that provides critical information such as frequency, operating mode, memory channel, and time. Users can configure various operational parameters, including tuning steps and bandwidth filters, to optimize reception for specific signals. This review highlights the FRG-100's straightforward interface and its utility for shortwave listening enthusiasts. The design emphasizes user-friendly adjustments for settings, which contributes to its appeal among those interested in general coverage reception.

The author discusses ways to display VHF and higher bands using a K3/10 as  transverter, NooElec Upconverter, SDR, and SDR-Console. He observed that the results were remarkable, with the tuned frequency visible at +/-100kHz. The K3 Interface Option (KXV3A) produces a buffered IF output at 8.213MHz, which is received using a NooElec NESDR SMArt SDR dongle and Ham It UP Upconverter. The SDR-Console program is utilized, with Omnirig synchronizing the SDR and K3. To configure the system, particular parameters are required, such as adjusting the IF frequency to 133.213MHz (125MHz + IF frequency) and inverting the spectrum. The Panadapter demonstrated ES activity at 10m, and modest software tweaks may be required for improved performance.

IOTA: OC-003 activation planned for November 01 – November 15, 2024 Operation modes: SSB, CW, RTTY , FT8, FT4, PSK Bands: 160 – 6m, QO-100

The CCXD Award (The Century Club of eXtreme difficulty is one of the most difficult awards to achieve. You are required to operate your home country from 100 DXCC countries. Founded in 2013, awards certificate is still awaiting presentation.

This resource details **cooling modifications** for Ameritron AL82, AL1200, and AL1500 HF amplifiers, specifically addressing heat issues encountered during high-duty-cycle digital mode operation. The author, WD4NGB, observed excessive heat in the tank area and band switch on an AL82, attributing it to insufficient exhaust over the 3-500 tubes and a complete lack of exhaust over the tank area. The modifications aim to prevent common failures such as damaged band switches and deformed insulating materials by increasing airflow and exhaust area. The page describes adding five holes to the chassis for enhanced cooling to the band switch and tank area, alongside enlarging the exhaust area over the inner 3-500 tube and the tank area on the amplifier cover, utilizing expanded metal for safety and RF shielding. The original cover featured 26.25 square inches of exhaust; the modified version significantly increases this to 48.5 square inches over the tubes and introduces an additional 15 square inches over the band switch. These changes are intended to resolve heating problems encountered during heavy, 100% duty cycle use in modes like RTTY or long SSB contests, which typically generate substantial heat. The article also discusses upgrading to a higher output fan, such as the G2E085-AA05-21, and modifying tube sockets for improved airflow and reduced back pressure, citing Tom Rauch (W8JI) of CTR Engineering as a source for parts.

AA DX Group was founded in March 1, 1974 in The Netherlands. Our members was more than 10000 from all over the World. Because during the years many of our members became "Silent Keys" or they are not active on the air anymore, we deceide to make new fresh group and to delete all old database. So, we are the new - old Alfa Alfa DX Group and you are welcome to be our member. We make avaiable all Alfa Alfa numbers for new and active CB members and SWL ( Shrot Wave Listeners ). Alfa Alfa World Wide DX Radio group is looking or ACTIVE CB Operators and SWL stations ! The New AADX team in in 2024 Main base in 178AA000 178AADX000 in Belgaria

TX5EU 2026 DXpedition to Raivavae Island, **OC-114**, within the Austral Islands, providing a detailed account of the German/Dutch team's operations. The resource outlines the participation of operators such as DL2AWG Guenter, PA2KW Evert, and DK2AMM Ernoe, who engaged in CW, SSB, RTTY, and various digital modes. It documents the real-world challenges encountered, including significant equipment failures and antenna damage to 80/60m, 30m, and 10m verticals due to adverse storm conditions. The page offers timely news updates on the expedition's progress, noting repairs to a power amplifier's 10/12m bandpass filter, which enabled three stations to utilize amplification. Earlier reports highlighted power failures and the loss of multiple power amplifiers, necessitating one station to operate barefoot FT-8 with 100W. The team's persistent efforts to repair antennas as weather permits are also detailed, reflecting the dynamic nature of remote island operations.

Operating an **Echolink** gateway on the 4-meter band presents unique opportunities for extending VHF communications, as demonstrated by the EI4FMG node. Situated at Fieldstown, Monasterboice, this gateway provides coverage across a significant portion of Ireland's east coast, leveraging a Tait TM8100 radio and an EI4JR Echolink interface logic. My own experience with similar setups confirms the importance of strategic site selection for maximizing reach, particularly with a 122-meter elevation above sea level. Access to the EI4FMG gateway, identified by node 57006, requires a **CTCSS** tone of 88.5 Hz, a standard practice for managing access and minimizing interference on shared frequencies. The system transmits with 15 watts of power and utilizes a Sigma CAT70 @5MAGL antenna, a configuration well-suited for regional VHF coverage. The gateway also features an auto-ID every 8 minutes, ensuring compliance and clear station identification. Users can interact with the gateway using various DTMF commands, allowing for connections to specific nodes, random repeater/link or conference nodes, and managing disconnections. These functionalities streamline the process of linking into the broader Echolink network, enabling local VHF operators to communicate globally through the internet backbone.