Search results

In this article, Steve G0UIH presents a straightforward guide for constructing a lightweight 15m 3 Element Yagi antenna with impressive performance metrics. With a focus on ease of construction and efficiency, the design boasts a nearly 8.2dbi forward gain and 30db front to back ratio. Utilizing readily available materials and a hairpin match for impedance matching, this Yagi offers broad bandwidth and simple tuning for optimal operation across the 15m band.

A concept to use common, low-cost parts to mount a VHF/UHF dual-band antenna to help people who have HOA restrictions, are renters, or desire low-visibility characteristics get on the air.

Originally designed by John Kraus, W8JK in about 1940, this antenna has some interesting properties. The W8JK antenna is 2 (Two) centre-fed double-dipole fed by a pair of anti-phase signals. Small size, simple antenna, offer nice performance but need a tuner. Tested in this project from 30m to 6m bands

Learn how to design and analyze a folded trifilar antenna for the 80-meter band. Based on a description from RAF antennas between 1940 and 1970, this article provides step-by-step guidance on modeling the antenna, calculating resonance frequency, adjusting dimensions, and verifying performance. Perfect for hams looking to improve their antenna setup for better transmission and reception on the 80M band.

Integrating a **160-meter vertical wire antenna** with an existing 80-meter Yagi system presents unique challenges for Top Band operation. This project outlines the author's experiences with seasonal antenna removal and reinstallation, a necessary task for agricultural land use. It details specific issues encountered, such as incorrect coil sizing and relay configuration problems, providing practical insights into common pitfalls. The article describes the iterative tuning process, comparing **NEC model** predictions with actual on-air performance. It emphasizes the importance of precise measurements and adjustments to achieve optimal resonance and impedance matching. The author shares lessons learned from troubleshooting, including the impact of ground system integrity and feedline considerations. Concluding with an antenna checkup, the resource addresses long-term maintenance aspects, including galvanic corrosion prevention and general upkeep for reliable operation.

This blog chronicles the development of an 80-meter vertical antenna for amateur radio operation. The author constructs a top-loaded vertical using fiberglass poles, achieving significant performance improvements over their previous end-fed wire antenna. Comparative testing using the Reverse Beacon Network and on-air contacts demonstrates 8-10 dB gain on the east coast. The project evolved to include 40-meter capability through a modified design featuring a four-wire vertical cage, loading coil, and strategic guying system. Despite challenges with signal wobble during windy conditions, the vertical consistently outperforms the end-fed wire, particularly for reaching distant stations during nighttime propagation.

Hamradio_copilot is an open-source tool designed for DXers and contesters who need real-time situational awareness. It is ideal for operators who want to visualize propagation trends instantly rather than scrolling through raw text streams of cluster spots. Rally acting as a copilot for your station, this tool transforms raw data into actionable intelligence. By visualizing Signal-to-Noise Ratios (SNR) across different bands, it helps operators make quick decisions on which band to prioritize or where to point their antennas, effectively showing not just who is on air, but where the propagation is currently open from your location. This is a fantastic information for avid contesters. The software aggregates data from two primary services: - Reverse Beacon Network (RBN) via Telnet. - PSK Reporter via MQTT feeds. It processes this data to generate a comprehensive HTML report featuring SNR heatmaps and statistical breakdowns by ITU Zone. Users can filter data by specific zones or country codes (ADIF), analyze historic time ranges, and optionally integrate solar weather data. The complete source code is available on GitHub, allowing for community customization. It is written in Python and uses SQLite for data management.

This project focuses on testing and comparing various antennas for receiving ADS-B (Automatic Dependent Surveillance-Broadcast) signals, utilizing software tools like RTL1090 and Virtual Radar with an RTL-SDR dongle. The goal is to evaluate the reception range ("ReceiverRange") and performance of different antenna types when tracking aircraft signals, particularly around the Amersfoort area. The project includes a comprehensive photo album documenting the antenna designs and setup processes, serving as a valuable resource for enthusiasts building ADS-B reception systems

An homebrew HF Magnetic loop made with 2m length of 6mm diameter copper pipe formed into a near circle as the low loss inductor, a short length of coax as a capacitor,a short length of mains cable, again as a fixed tuned capacitor, a tunable 365pF air spaced capacitor, and a small Jackson C804 airspaced variable with a small 3-35pF trimmer in parallel

SkyRoof is an open-source, 64-bit Windows application designed for amateur radio operators and satellite enthusiasts, combining satellite tracking and Software Defined Radio (SDR) functionality in a unified platform. The software provides real-time satellite tracking, pass predictions, and visual representations through Sky View, Earth View, and Timeline displays. It features an SDR-based waterfall display covering VHF/UHF satellite segments with Doppler-corrected frequency scales, automatic satellite labeling, and visual tuning capabilities. SkyRoof supports various SDR devices (Airspy Mini, SDRplay, RTL-SDR), external transceiver CAT control, and antenna rotator integration. The application automatically downloads satellite data from SatNOGS and other sources, offers voice announcements for satellite passes, and includes comprehensive frequency control with Doppler tracking, manual corrections, and RIT functionality for enhanced satellite communication operations.

Constructing an effective antenna support system often involves safely elevating wire antennas into trees or over obstacles. This resource details the build process for the WT8WV "Colossus" air cannon antenna launcher, a pneumatic device designed to project a pilot line over elevated structures. It specifies the use of readily available PVC pipe components and standard hardware, outlining the exact materials required and providing step-by-step assembly instructions for a robust, low-cost solution. The article presents a practical alternative to traditional methods like slingshots, emphasizing the launcher's utility for Field Day operations and general antenna deployment. It includes a comprehensive list of parts, such as 2-inch and 1-inch PVC pipe, various fittings, a sprinkler valve, and a bicycle pump valve, detailing their integration into the final assembly. The total cost for materials is estimated at around $40 per unit, making it an accessible project for many radio amateurs. Crucially, the guide incorporates essential safety precautions for operating a pneumatic launcher, covering aspects like pressure management and projectile selection. It also features multiple photographs illustrating the construction phases and the completed device, offering visual clarity to aid builders in replicating the design.

Over 1000 _Elecraft_ KX2 owners have benefited from the Kx22 Heatsink, experiencing cooler rig temperatures and higher output powers. PAE manufactures these heatsinks, along with AC power supplies for HF transceivers, remote power relays, and Ethernet relays, with all machined products manufactured in the **USA**. PAE distributes _Fair-Rite_ Mix 31 ferrite snap-it cores and toroid cores, essential for RFI suppression and impedance matching in amateur radio setups. The product line also includes commercial monitoring antennas, UQUI transformers, ULP AC power filters, and 3M conductive adhesive copper tape, catering to various station build-out and maintenance needs. The AM1 Portable Antenna Mount System and its AM1-VA Multi-Angle Adapter offer flexible antenna deployment options. PAE ensures careful packing of fragile ferrite products, with shipping cost adjustments communicated post-order for larger, heavier combinations to guarantee safe delivery.

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.

The FT-991 is a nice small size and lightweight radio, it is perfect for portable operations. It can be carried along with a laptop computer as hand luggage in airplane. The weak point of this radio, is it does not have a separate RX antenna capability. Therefore i decided to add this feature. On the back side of the radio a BNC connector is added to connect the RX antenna and a switch is fitted to select between RX antenna or main antenna.

This article presents an RF Choke featuring an 11-bifilar turn winding of #14 house wire on a Fair-rite FT240-31 toroid. The choke is enclosed in a 3D-printed case from Thingiverse, though this may pose thermal concerns at higher power levels. With SWR concerns up to 30MHz, the author plans to employ two series chokes at the rig input for improved performance. This choke offers versatility for portable use, with potential mismatch resolution using an antenna tuner. Further testing is anticipated upon the arrival of new cables.

The QRP Cluster provides a dedicated platform for _QRP_ (low power) amateur radio operators to self-spot their on-air activity. This web-based service allows users to post real-time information about their current operating frequency, modulation mode, equipment used, and transmit power. It facilitates QRP-to-QRP contacts and helps other low-power stations locate active QRP signals across various bands. Unlike general DX clusters, the QRP Cluster focuses exclusively on low-power operations, fostering a community for QRP enthusiasts. It enables operators to share details such as **5 watts** or less output, often specifying antenna types or unique portable setups. The platform supports the discovery of QRP stations for casual QSOs, contests, and award hunting, enhancing visibility for stations that might otherwise be overlooked on higher-power clusters.

The PA0FRI Unbalanced/Balanced ATU is a home-built antenna tuner designed to efficiently match a W8JK 2-element beam antenna fed with a 450-ohm twin lead. Based on PA0FRI’s S-Match design, it optimizes energy transfer while maintaining balance, reducing losses, and ensuring proper radiation. The tuner uses a roller inductor, air variable capacitors, and a T200 iron powder coil, allowing fine-tuning across 14-50 MHz. Extensive lab tests confirm minimal attenuation and precise impedance matching, making it a reliable and efficient ATU for balanced antennas.

This article explores the marriage of amateur radio and bushcraft, advocating the pleasure of setting up a portable station in nature rather than operating from the confines of a vehicle. The Parks on the Air (POTA) programme is highlighted as a catalyst for outdoor radio activities. The author shares his experiences and techniques, from transporting equipment into the wilderness to setting up shelters and antennas. Knot tying skills and the use of frogs are emphasized for efficiency, and a unique method for launching wire antennas is described. The article emphasizes the synergy between amateur radio and bushcraft skills, enhancing the enjoyment of radio operations in wilderness environments.

OM0ET manufacture high capacity variable air capacitor and tuning unit designed for Magloop antennas. OM0ET explains features and benefits of this antenna, such as easy assembly, wide frequency range, and improved efficiency. Ideal antenna setup for indoor or outdoor use, offering better QSO performance and radio listening experience. The author, identified as OM0ET, shares insights on the design and functionality of the equipment, making it a valuable antenna for portable operations.

The field strength meter (FSM) is a very useful addition to any HAM toolbox. If you are messing around with antennas, or building PA's, or trying to repair some TX gear, the FSM will come to your rescue when there is doubt about the output level.

The 1/4 wavelength vertical antenna project, initially designed for 20 meters, has evolved into a versatile portable solution covering 10 through 60 meters. K0BXB details its construction, emphasizing a bottom-loaded design with a tapped loading coil and four 10-foot counterpoise wires. The author shares personal experiences and field results, including **18 QSOs** during a park activation on 17m and 30m with 10 watts, and a **2,435-mile** contact with a contest station in Bonaire on 20m using 5 watts. Comparisons are drawn to commercial offerings like the _Wolf River Coils TIA_ and _QRPGuys Triband Vertical_, highlighting the DIY antenna's small footprint, light weight, and ease of tuning for POTA activations. The resource includes insights into using test equipment such as the _NanoVNA_ for SWR optimization and discusses various radiator lengths, from 17-foot wire to a 102-inch whip, demonstrating adaptability for different portable setups. Construction tips cover coil winding, tap placement, and connecting feedlines and radials using common components.

The resource discusses antenna families frequently utilized by _Parks On The Air_ (POTA) activators, focusing on the specific requirements for portable operations. It highlights the need for lightweight construction, rapid deployment, and sufficient efficiency to achieve the minimum **ten contacts** required for activation. The guide addresses adaptability to diverse field conditions, including the presence or absence of trees and varying ground surfaces. For each antenna type, the article provides a principle diagram, outlines its operational strengths, and details its inherent limitations. It also includes external links to practical field experiences, offering real-world context for each design. The POTA program, which involves setting up a complete station in a park, often within **thirty minutes**, underscores the antenna's critical role in successful activations.

The Pikes Peak Radio Amateur Association (PPRAA) serves as an ARRL Special Service Club, providing a calendar of events and activities for its members and the wider amateur radio community. The resource details upcoming events such as the USS Pueblo Memorial Museum Ships Weekend activations, a Cubical Quad Antenna Workshop, LARCFest, and various hamfests including Dayton Hamvention and Duke City Hamfest. It also lists on-air activities like a FreeDV digital voice mode event on 10 meters, a Black Friday Simplex Event on 2M and 70cm, and a 10m event for Technician class operators, emphasizing SSB privileges from 28.300 to 28.500 MHz. The PPRAA's event schedule includes educational opportunities like a Technician Class and a Soldering Workshop, alongside social gatherings such as the PPRAA Picnic and Car Show. Past event summaries highlight successful activities like the 2024 Megafest Raffle, Winter Field Day, and multiple fox hunts utilizing frequencies like 147.420, 147.480, and 147.540 MHz. The club actively supports POTA activations, exemplified by their AF0S park activation at Cheyenne Mountain State Park, and participates in historical commemorations like the USS Pueblo Memorial operations, demonstrating a broad engagement across various amateur radio facets.

This article explains the trick of how to shorten and lengthen pairs of radials to make a 2-band ground plane antenna. Included is a "Table of Multi-Band Possibilities" covering the range of 6 to 40 meters.

Integrating a _Software Defined Radio_ (SDR) into an existing ham radio setup involves connecting it with a standard transceiver (TRX), power amplifier (PA), and antennas. The core component is a splitter box that facilitates the connection between the TRX and the SDR, allowing for simultaneous operation without modifying existing equipment. In receive mode, the splitter ties the antenna inputs of both the TRX and a direct conversion receiver (DC RX) together. During transmission, the DC RX input is grounded via a fast telecom relay controlled by the transceiver's -SEND signal, incorporating a 10ms delay for safety. The splitter box includes a 3.7 dB input attenuator for impedance matching and acts as a protective fuse for the DC RX input. Ground loops are mitigated using common mode balun transformers, while the DC RX input is insulated with a broadband transformer. An audio switch box complements the setup, enabling users to listen to either the main transceiver, the SDR output, or both simultaneously. This configuration ensures noise immunity and safety, with the splitter housed in a screened box made from PCB material. On-air tests, such as the CQ WW 160m CW DX Contest, demonstrate the system's effectiveness, showcasing the SDR's ability to handle crowded band conditions with superior selectivity and dynamic range. The SDR's narrow bandwidth filters and waterfall display provide significant advantages, allowing operators to detect weak signals amidst strong interference. The integration of SDR with conventional radios offers enhanced operational flexibility and performance in challenging environments.

The ICOM IC-705, a popular QRP transceiver for portable operations, often presents unique challenges for field deployment. This resource details practical solutions for common portable setup issues, particularly for _Parks on the Air_ (POTA) activations. It describes a custom bracket for connecting antennas to the IC-705 through a backpack's antenna flap, utilizing a BNC female-to-female chassis mount connector to mitigate cable tangles. The author shares experiences with a DIY magnetic loop antenna, noting its ease of tuning with the IC-705 and successful CW contacts on 40 and 20 meters over distances exceeding **1000 miles**. Another modification presented is a strain relief solution for the microphone cord, replacing the standard spring clip with an easier-to-attach method. The page also mentions using a _Wolf River Parks antenna_ for POTA activations and references the QRPGuys DS-1 antenna as another portable option. Firmware updates and integration with an LDG Z11-Pro II auto-tuner are also discussed.

The article discusses the evolution of antenna designs, specifically focusing on the upgrade from the W7IUV rotatable Flag to the Waller Flag. Author Pierluigi Mansutti IV3PRK shares insights on modeling these antennas using EZNEC software, detailing their performance in noisy environments. The W7IUV Flag proved effective for receiving signals, while the Waller Flag, developed by NX4D and N4IS, offers improved front-to-back ratios but requires careful consideration of signal levels and noise management. The article emphasizes practical modeling results and interactions between different antenna setups.

Moto-QRP setups offer compact, weatherproof QRP transceivers for portable ham radio use, ideal for motorcycle and backpack operations. The YouKits HB1A MKII, a 5W CW rig, is paired with a lightweight long-wire antenna and an Elecraft T1 tuner for efficient field communication. This setup fits in panniers, enabling operators to explore parks and remote locations. Accessories include a durable Morse paddle, FCC documentation, and essential logging tools, making it a perfect choice for adventurous QRP enthusiasts.

Fifty-one MHz operation, often called the "magic band," benefits significantly from a well-designed antenna, and this resource details the construction of a rigid 6-meter _Moxon antenna_ using common DIY store materials. The author, 4L/G8BAG, shares his experience with the 6m band, highlighting its potential for long-distance contacts, with single-hop sporadic E propagation enabling QSOs up to **2,500 km** and multi-hop contacts reaching **10,000 km**. The project emphasizes cost-effectiveness and durability, utilizing yellow gas pipe with an internal stainless steel lining for the antenna elements. The article provides specific dimensions for the Moxon rectangle, derived from the 12mm internal diameter of the gas pipe's steel core, rather than the outer plastic. It also details the use of white PVC water pipe for insulators and mounting, ensuring a tight fit with the yellow gas pipe. Initial testing with an MFJ antenna analyzer showed an excellent 1:1 SWR across the 50-52 MHz range, even when using 75 Ohm satellite cable as a feeder. The construction process is straightforward, involving cutting and bending the gas pipe, fitting insulators, and connecting the feedline. The author's successful on-air results, including a 1000 km contact with a temporary vertical, underscore the effectiveness of the 6m band and the Moxon design. The resource concludes with a note on exploring heavier gauge gas pipe for future 10m antenna projects.

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.

Operating amateur radio satellites presents unique challenges, particularly concerning antenna design and signal propagation. Juan Antonio Fernández Montaña, EA4CYQ, recounts his three-year journey into satellite communication, starting with initial guidance from EB4DKA. His early experiments involved a portable 1/4 wave VHF antenna with four 1/4 wave ground planes, designed for hand-held use to adjust polarity. This setup, paired with an FT-3000M transceiver, allowed full-duplex operation on **VHF** transmit and **UHF** receive, proving effective for early contacts on satellites like AO27, UO14, and SO35. EA4CYQ's experience highlights the critical role of coaxial cable loss and antenna polarization. After encountering significant signal degradation with longer RG213 runs, he experimented with a 1/2 inch commercial cable, noting improved reception but persistent fading due to varying satellite polarities. This led to the construction of an **Eggbeater II** antenna, an omnidirectional UHF design offering horizontal polarization at the horizon and circular right polarization at higher elevation angles. Subsequent modifications resulted in the directional **TPM2** antenna, which provided sufficient gain for LEO satellites with a wide 30-degree lobe, enabling consistent contacts from his home station. The article concludes with practical insights on the performance of the Eggbeater II for both UHF and VHF, and the TPM2 for UHF, emphasizing their utility for portable and fixed operations. EA4CYQ's journey underscores the iterative process of antenna development and the importance of adapting designs to overcome real-world propagation challenges in satellite communications.

DX web cluster that offers features for both registered and unregistered users. Unregistered users can view spots, filter by band and mode, search for callsigns, while registered users get all that plus the ability to submit spots, upload logs, see DXCC country status, antenna pointing info, real-time maps of spots, email alerts for DXCC countries on-air, and more. Basically, register for free to get the full DX cluster experience.

Learn about the HAMTV Digital Amateur Television (DATV) transmitter on the International Space Station (ISS), transmitting video and audio in MPEG-2 format using the DVB-S protocol. Discover its history, installations, failures, and repairs, as well as the current status and live video feed. Explore the technical details and challenges of the HAMTV transmitter, including power output, polarization, and antenna location. Find recordings of previous transmissions and understand the potential signal reflections caused by various ISS components. Stay updated on the latest developments and activities related to HAMTV from the ISS.

Join Thomas (K4SWL) as he shares his experience activating a POTA site using the Elecraft KX2 AX1 combo. Follow along on his journey from a podcast recording session to a quick POTA activation, showcasing the ease and efficiency of this portable setup. Discover the joy of getting on the air with minimal setup time and maximum enjoyment, perfect for hams looking for a grab-and-go solution. Learn about the benefits of using the AX1 antenna and how it can enhance your portable operations, all while supporting QRPer.com through affiliate links.

Demonstrates the construction of a portable 2-meter repeater system utilizing a **Yaesu DR-1X** transceiver, configured for both analog FM and C4FM digital voice operation. The design emphasizes portability, robustness, and effective thermal management, incorporating a "wind tunnel" airflow system with a fan to maintain transmit module temperatures at 38 degrees Celsius during continuous operation. The system integrates a diplexer, control head, and is housed in a compact, lightweight case weighing under 8kg, designed for single-person deployment. Covers practical considerations for field deployment, including power sources, antenna types, and the overall system architecture for public service events and emergency preparedness. The resource details the modular "wrap around" construction, showing how components like thermal switches for fan control and Anderson Powerpole connectors are integrated. It highlights the system's ability to provide reliable communications support for club activities and emergency communications.

The XW4DX DXpedition website documents the amateur radio operation from Laos, a country ranked #98 on Clublog's Most Wanted list. This resource provides insights into the planning and execution of a significant DXpedition, including antenna choices like _Hexbeams_ at 14m, a 4-square for 40m, and a top-loaded vertical for 160m. The team, comprising operators such as _F4BKV Vincent_ and _F2DX Patrick_, focused on challenging paths, particularly towards the North American East Coast, where Laos is #41 most wanted. Operational constraints included prohibitions on 6m, 30m, 60m, and 80m bands within Laos, necessitating a focus on other HF frequencies, especially 160m and 40m. The expedition utilized up to five stations simultaneously, with equipment transportation being a major logistical challenge, partially mitigated by direct shipments from _Spiderbeam_ and donor support. The expedition ran from November 16th to 27th, 2023, with the complete XW4DX log uploaded to LoTW by December 23rd, 2023. This site serves as a historical record of their efforts to put Laos on the air for DXers worldwide.

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.