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The Newbury and District Amateur Radio Society (NADARS), operating under the callsign G5XV, details its extensive history spanning **104 years** and its operational activities. The resource outlines regular monthly meetings held at Acland Hall, Hermitage Rd, Cold Ash, RG18 9JH, typically featuring informal lectures on radio-related topics. It also highlights the club's engagement in various social and radio events, including participation in contests such as _IOTA_ and _NFD_. NADARS maintains regular daily nets on both 2M and HF bands, providing specific details for members to join. A significant annual event is the Newbury Radio Rally, hosted each summer at the Newbury Showground, which attracts visitors nationwide and features radio and computing sales, club stands, and live demonstration stations. Information on upcoming events, including the next Newbury Radio Rally scheduled for July 5th, 2026, is also provided.

This article describes the construction of a 9,50 m long dipole for the 30 m band (10.1 MHz to 10.15 MHz). It was designed to be mounted ca. 6 m above ground inside an attic. The calculations were performed by OE1MEW

Spy Numbers Stations are shortwave radio stations that are speculated to have been broadcasting since World War I. The true origin and purpose of them are unknown. A popular theory is that these stations are intended for spies in the field using a One Time Pad. Another theory is that they are used in drug smuggling operations.

The _G3TSO_ Mobile Antenna Page details construction and tuning methods for mobile antennas operating across **10 to 160 metres**. The content describes a Hustler-based design, optimized for RF performance and vehicle speeds, featuring centre loading. For optimal operation on various bands, the loading coil placement requires clearance from the vehicle body. Antenna resonance is critical for efficient mobile operation. A mobile antenna's base impedance may be as low as 27 ohms, requiring specific matching to achieve maximum radiation, as a minimum SWR at the transmitter does not always indicate resonance or maximum output. Tuning involves physical adjustment of antenna length to achieve resonance at the operating frequency. The _G3TSO_ page outlines a tuning procedure utilizing a low-power signal source and a field strength meter to identify maximum radiation before impedance matching. Loading coil placement, either at the base, center, or top of the antenna, influences radiation efficiency and mechanical stability for mobile installations. Centre-loaded whips, such as the Hustler design, offer a compromise between efficiency and stability, often for single-band operation. Helically wound antennas, including those for **28 MHz**, may present base impedances around 17 ohms, resulting in a 3:1 SWR at resonance. Low resistance grounding at the antenna base is also specified for optimizing performance and minimizing RFI during mobile operation. DXZone Focus: Mobile | Any | Antenna Tuning | HF

Ground Station offers real-time satellite tracking and radio communication capabilities, primarily for amateur radio operators engaged in satellite operations. It utilizes **TLE data** from sources like CelesTrak and SatNOGS for precise orbital prediction and integrates with various SDR devices, including RTL-SDR, SoapySDR, and UHD/USRP radios, to receive live signals. The software provides automated antenna rotator control and **Hamlib-compatible** rig control with Doppler correction, crucial for maintaining signal lock on fast-moving LEO satellites. It supports IQ recording in SigMF format and decodes several digital modes such as SSTV, FSK, GFSK, GMSK, and BPSK with AX25 USP Geoscan framing. Dedicated interfaces are available for satellite tracking, SDR waterfall displays with live transcription and packet decoding, and telemetry packet viewing. Users can manage TLE data synchronization and SDR hardware, along with browsing decoded outputs through an integrated file browser. An observations dashboard and DSP topology view further enhance the operational experience, providing comprehensive tools for monitoring and analyzing satellite passes.

Mounting on roof at the right ground level can greately impact on antenna performances because will affect the radiated angle of energy.

The 80-meter Skyloop antenna, a top-performing HF antenna, excels in weak signal work, low-noise operation, and omnidirectional coverage. Ideal for fixed stations, it delivers strong performance at low power, outperforming many alternatives, including 80m half-wave end-fed antennas. Requiring significant space for deployment, it’s well-suited for NVIS and groundwave use. Though not portable, it’s cost-effective and durable, with minor maintenance needs. Tuning may require adjustments for optimal resonance. It’s a standout for base stations, though a lighter portable version could enhance its versatility.

The weather station described here uses a TTGO v3 1.6.2 module and various sensors. It displays the data on an OLED screen and transmits them among a choice of protocols to the APRS, APRS-IS, Wunderground servers or via an MQTT broker. APRS data is transmitted on 433.775 MHz (can be changed) using the LoRa protocol. APRS beacons picked up by iGate gateways are then transmitted to APRS servers.

An Inverted-L with its long leg sloping to the ground. It will still work very good, even if the horizontal wire has to be sloped diagonally to the ground, as long as you have enough horizontal space to keep it at about a 45 degree angle or more from the pole.

Zenith Tracker offers real-time satellite tracking, pass predictions, and radio hardware integration for ham radio operators. The platform includes an interactive world map showing satellite positions, footprints, and ground tracks, as well as a polar radar visualization for detailed pass analysis. Users can view upcoming passes, set filters, and receive notifications. Integration with CSN Technologies S.A.T Hardware and QTRigDoppler allows for automatic radio control, antenna tracking, and transponder management. The platform also offers APRS message interface, grid square-based location input, and API integration for rover activations. Zenith Tracker is recommended for both general users and those needing advanced hardware integration.

Signal to Noise Ratio, definition and application to Radio Communications. Signal to Noise Ratio (SNR) is a figure of merit that compares the level of a desired signal to the level of background noise.

This document details the construction of a multi-band end-fed antenna, suitable for situations with limited space for larger antennas. The design utilizes a 1:49 to 1:60 impedance transformer to match a half-wave wire antenna fed at one end. Compared to a traditional dipole, this antenna resembles a highly unbalanced Windom antenna with one very long leg and a virtual short leg. The design eliminates the need for radials but relies on the coax cable shield for grounding. The document recommends using at least 10 meters of coax and installing a common mode filter at the entry point to the shack for improved performance.

Mad your own simple FS meter. It is the simplest thing to make and is good enough to see if the antenna under test is radiating more power than your old ground plane, old mobile vertical or just radiating at all in a particular direction or in all directions.

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.

Modeling an antenna over real terrain gives you a visual picture of how terrain impacts performance. You can use a model to determine optimum height for antennas on an existing tower, Compare different tower locations for performance, Compare different sites for performance

The Beverage we use is a DX Engineering RPS-1 dual directional 360 foot 109,7 m, oriented due North/South, six feet 1,8 m off the ground. The antenna uses 450 ohm ladder line as the antenna, and 75 ohm RG-6u for the feedline. The antenna runs atop the fence between our property and 5 acres of pasture next door.

This article presents the C-Pole antenna project, a compact, ground-independent vertical antenna designed for amateur radio operators. It features a folded half-wave dipole configuration that eliminates the need for radials, making it suitable for various locations, especially in deed-restricted areas. The C-Pole offers efficient performance with a 2:1 SWR bandwidth of approximately 3%, and it can be easily constructed using common materials. Additionally, the article discusses practical aspects such as feed-point impedance transformation and balun design to optimize functionality and minimize losses.

Helical antenna or helix antenna is the antenna in which the conducting wire is wound in helical shape and connected to the ground plate with a feeder line. It is the simplest antenna, which provides circularly polarized waves.

High Altitude Ballooning makes for a challenging project that sometimes turns into an engrossing hobby. Whilst it is not rocket science it does encompass a wide range of fields (sometimes literally) and there is a lot to learn before you send your first flight up into the sky.

A QSL Cards collection divided into North American Shortwave Pirate Radio QSLs abd European Shortwave Pirate Radio QSLs

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.

A homemade quarter wave ground plane anntenna for 4 meters band.

Operating from Banana Island, Sierra Leone (AF-037), the 9L2019 DXpedition by F6KOP and a ten-operator team used the callsign 9LY1JM from January 9-21, 2019. This detailed report covers the logistical challenges, including securing visas and licenses with local assistance from Mark 9L1YXJ and Gregory of Dalton’s Guest House. The team deployed monoband quarter-wave verticals on the beach and two Beverage on Ground (BOG) antennas for Europe/Asia and the USA, operating four stations simultaneously. Technical hurdles encountered included high tides submerging antennas, requiring repositioning, and persistent QRM between closely spaced stations, mitigated by doubling filters. CW signal irregularities at 30-32 WPM were resolved by PC and WINTEST restarts. A significant FT8 logging bug was identified and corrected with on-site software. Despite these issues, the team logged over 4,000 QSOs in the first 24 hours, averaging 5,000 QSOs daily, with a peak of over 6,000 in one day. Propagation varied, with excellent 160m conditions on January 12 yielding over 750 QSOs, and a later four-hour opening pushing the 160m total past 1,600. High bands were challenging due to low solar activity, but mid-bands provided intense pileups and rapid continent-wide contacts. The DXpedition concluded with nearly 50,000 QSOs, including a successful school QSO with Collège Doisneau de Sarralbe (57), managed by F1ULQ and F6KFT.

This project details the construction of a compact, circularly polarized Quadrifilar Helix Antenna (QHA) designed for 146 MHz operation. The antenna features a 1/2λ1/2λ helical design with a 2.6:1 aspect ratio, providing 4.5 dB gain and a spheroid radiation pattern. It is ground plane independent and compatible with both vertical and horizontal polarizations, making it ideal for terrestrial and space communications. The design includes step-by-step instructions for building the antenna using readily available materials like aluminum rods, PVC pipes, and RG-58 coaxial cable. The antenna's performance has been validated through comparisons with commercial omnidirectional antennas, showing superior results.

The project details the construction of a portable multiband mobile antenna, designed for rapid deployment with an _Elecraft KX3_ for /M operations. It utilizes a coil and the car body as a counterpoise, enabling operation across multiple HF bands. The article presents a table of coil tap positions for 40m, 20m, 17m, 15m, and 10m, along with corresponding SWR measurements, demonstrating an SWR below 1.5:1 on all tested bands. Photographs illustrate the antenna's components, including the coil winding and mounting mechanism, and its deployment on a vehicle. The author provides insights into the antenna's performance characteristics, noting its resemblance to a vertical dipole despite the unconventional ground plane. The resource includes a parts list and construction steps, making it reproducible for other radio amateurs.

Demonstrates the ZS6BKW multiband HF antenna, a design by ZS6BKW (G0GSF) that improves upon the G5RV by offering direct resonance on multiple bands without an antenna tuner. The resource details the antenna's 90-foot length and 40-foot 450-ohm twin lead downlead, emphasizing its suitability for hams with limited space or budget. It covers both horizontal and inverted-V configurations, noting the inverted-V's single-support advantage and the importance of maintaining an apex angle of at least 90 degrees to prevent signal cancellation. The author, G3UKV, shares his preference for 450-ohm twin lead over 300-ohm due to its superior strength and lower losses, especially in wet conditions, drawing from his extensive field experience. The document presents recorded SWR and impedance (R) measurements taken with an MFJ Antenna Analyzer, confirming excellent performance on 40m, 20m, 17m, 12m, 10m, and 6m, often with SWRs below 1.3:1. It also discusses the antenna's tunability on 80m with an ATU and suggests a method for 160m operation. G3UKV recounts receiving "excellent reports" on 7 MHz and 14 MHz, validating the antenna's effectiveness. Practical advice includes keeping antenna ends clear of ground by at least a yard to avoid detuning and the recommendation of a 1:1 current balun where the 450-ohm feeder connects to 50-ohm coax.

Ham radio enthusiasts must prioritize lightning protection for their stations and homes to mitigate the risks associated with lightning strikes. Effective lightning protection involves dispelling myths, understanding the actual risks, and implementing proper grounding and surge protection. Key strategies include grounding all connections, protecting cables entering the station, and using surge protectors for power lines and control cables. Good grounding is essential for effective lightning protection.

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.

Presents an interactive online **Moxon antenna designer** tool, enabling radio amateurs to configure and analyze lightweight Moxon antennas for HF and VHF bands. Users can specify design frequency, element lengths, wire diameter, insulation, and support height. The tool visualizes the antenna in interactive 3D graphics and generates comprehensive performance charts, including azimuth, elevation, 3D, and polarization radiation patterns, VSWR charts, antenna current diagrams, and Smith charts. It also allows selection of various ground types (e.g., very poor soil, salt water, free space) to model environmental effects on antenna performance. The designer provides insights into how physical dimensions and ground conditions influence key antenna parameters like forward gain, front-to-back ratio, and feed-point impedance, which is typically close to 50 ohms. It also includes a feature to model the effect of coaxial cable losses on **VSWR** at the transmitter end, distinguishing it from the feed-point VSWR. This helps operators understand the actual radiated power efficiency versus the apparent match at the transceiver, offering a practical perspective on antenna system performance in portable operations.

The quarter-wave Marconi working against ground is a popular and inexpensive antenna for 160 meters. A lot of newcomers to the band favor this simple antenna because it's easy to put up, it isn't too big, and it works.

7MHz to 30MHz operation is achieved with a magnetic-mounted HF antenna designed for car roof deployment, capable of handling 100 Watts without an external antenna tuner. The design incorporates a large base-loading coil with multiple taps, allowing for frequency selection across various HF bands. This coil effectively increases the electrical length of a short telescopic antenna element, compensating for its inherent capacitance. Construction involves 3D-printed components for the coil former and support structures, though conventional building methods using plastic drainpipes are also suggested. The car body serves as the ground plane, with the coil assembly mounted on a 500mm square metal plate secured by super neodymium magnets. Protection under the magnets is advised to prevent vehicle scratches. Detailed instructions cover winding the 30-turn coil with 2.5mm diameter household electrical cable, assembling the 3D-printed parts, and making soldered connections. Taps are staggered every five turns for precise frequency adjustment. Performance examples include a 7913km contact to Japan using a 1.5m element and 100 Watts, demonstrating low-angle radiation and omni-directional pattern with minimal S-point loss compared to a full quarter-wave.

A 5/8 λ antenna, often thought to be ideal for all frequencies, has unique characteristics that don't universally apply. First introduced for medium-wave radio, it works optimally at 225° antenna length over ideal ground, yielding high efficiency. However, at VHF and higher frequencies, it offers no advantage over other antennas due to real ground conditions and complex matching requirements. DIY calculators provide only rough estimates, useful as a starting point for simulations, not for precise builds.

This page provides a detailed guide on how to build your own radioless Allstar node for ham radio operators. It includes information on power supply, components needed, wiring instructions, and tips to avoid common issues like ground loop hums. The author shares personal experiences and recommendations for specific components like microphones, audio amps, and sound fobs. Whether you're a beginner or experienced ham radio operator, this DIY project can help you set up a cost-effective and functional Allstar node for communication purposes.

This page allows hams to design a vertical-plane delta-loop antenna for a single amateur HF band in different configurations. By choosing different feed-point positions, operators can observe variations in polarization properties, radiation patterns, and feed-point impedances. Users can generate radiation pattern plots, VSWR charts, antenna current diagrams, and Smith charts for their antennas over various ground types. Through adjusting the antenna's physical dimensions and refreshing the plots, hams can gain insights into the antenna's performance in the field. The page also discusses how elevation radiation patterns may change based on the antenna configuration and feed-point position.

Experimenting and testing vertical antenna for HF bands on mobile operations.

To use the RF Exposure Calculator, fill-in the form with your operating power, antenna gain, and the operating frequency. Depending on how far above ground the RF source is located, you might want to consider ground reflections too.

The author shares a unique experiment with a 200ft Grasswire antenna—laying wire directly on the ground. Despite inherent losses, the setup enables successful radio communication with a Kentucky station, highlighting the antenna's practicality for portable use with minimal power.

In the pursuit of an affordable matching and SWR indication solution for the Pixie-based transceiver system this T-Tuner and SWR bridge unit, while not groundbreaking, proves to be a cost-effective performer. With real-world impedance testing yielding a worst-case loss below 0.9 dB, the unit efficiently matches all bands on 80 M to 10 M ham bands, making it a valuable addition to the QRP system.

The All-Copper J-Pole Antenna Construction for 2 Meters document outlines a specific build methodology for a VHF base station antenna. It addresses common issues like dissimilar metal corrosion and feed line degradation often encountered with aluminum J-Pole designs, proposing an all-copper and brass solution with soldered connections for enhanced durability and electrical performance. This resource provides a comprehensive parts list in Table 1, detailing precise copper tubing lengths and other necessary hardware components. The design emphasizes DC grounding, which eliminates the need for insulating materials and simplifies installation, contributing to a robust and weather-resistant structure. Michael P. Hood, KD8JB, details an assembly process estimated to take approximately one hour, with total material costs projected under $15. The antenna's construction focuses on rigid copper tubing and fittings, ensuring long-term integrity for 144 MHz operation.

For amateur radio operators engaging in portable operations like SOTA or POTA, rapid deployment of an effective antenna system is paramount. This video resource details the assembly process for the Buddipole multiband dipole antenna, showcasing its components and how they fit together. Rob, VK5SW, systematically presents the mast, coil arms, radiating elements, and the VersaTee hub, emphasizing the modular design that allows for quick configuration changes across various HF bands. The demonstration highlights the antenna's adaptability for different operating environments, from a ground-mounted vertical to a horizontal dipole. The video illustrates the ease with which the antenna can be packed and deployed, making it a practical choice for activations where setup time is limited. The Buddipole's design facilitates efficient band changes and tuning, crucial for maximizing QSO opportunities during field operations.

This page provides a detailed guide on how to receive WWVB 60 KHz time signals using the Everset ES100 module with an Arduino Due microcontroller. It explains the background of time standards and the significance of WWV radio stations in maintaining these standards. The content is useful for ham radio operators interested in time synchronization, scientific research, navigation, and radio communications. The article is written by Keith Greiner, who shares his project inspired by his passion for the subject. For more projects by the author, visit the provided links.

This page provides information about building a Beverage antenna for hams. The article discusses using a 60m wire on the ground to create an effective antenna for amateur radio operators. Learn how to set up and optimize this type of antenna for better reception and communication. This describes a low-noise receiving Beverage antenna setup for low bands, using a N30 cup core transformer for 1:4 impedance matching (likely 50:200 Ohm), RG-58 feedline with heavy common-mode choking, and conduit for wire burial.

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.

Antenna patterns are all about interference. Presentation on wire antennas for HF bands. Dipoles, horizontal and vertical dipoles, effects of ground on radiation patterns, multi-band wires antennas. Knowing what you should expect from the radiation patterns for waves on your wires will help you choose what will work best for your needs. The principles of interference can lend insight into what to expect from a wire antenna.

A half wave wire that is tuned for resonance on 80m will NOT be resonant on 40m despite a precise harmonic relationship between the two bands. The End Effect is caused by a capacitive coupling between an unterminated wire end and the ground.

The 8m ISM band, a unique frequency range between 10m and 6m, holds potential for amateur radio enthusiasts, yet it remains largely unallocated. This spectrum offers fertile ground for research and self-training. The author's experience with low-power transmissions and WSPR testing highlights the band's capabilities and the need for a narrow, speech-free amateur allocation to encourage experimentation. Discover the world of 8m ISM radio exploration and its future possibilities.

A C-Pole Antenna for QRPxpeditions describes a DIY C-Pole antenna designed for QRP (low-power) expeditions, inspired by KF2YN’s ground-independent vertical model. After adjustments, it achieved a 1:1 SWR at 14.060 MHz, rising to 2.5:1 at 14.35 MHz. A choke balun, comprising 15 turns of RG8X around a 4” can, was essential for optimal performance. Compact and self-supporting, the antenna enables reliable communication with minimal setup. Contacts included stations across the U.S., and even a 4,600-mile connection to Spain using only 5 watts.

Learn how to construct a balanced Antenna Tuning Unit (ATU) for your ham radio equipment. Follow the instructions provided by Bengt, SM6APQ, to create a variable capacitor insulated from the ground for additional safety. Discover how to set up the ATU for the 20 to 10m band with proper spacing between coils. Use low power when adjusting the ATU for lowest SWR. Avoid using switches and opt for banana plugs for flexible connections. Visit the Creative Science Centre website for more information and resources on ATU construction.

Delta loop antennas, particularly the 30 meter variant, offer unique advantages in terms of vertical polarization and omni-directional coverage. The construction process detailed by VE3VN highlights common mechanical and electrical challenges faced by amateur radio operators. Key design considerations include minimizing interaction with existing contest band antennas, achieving low elevation angles for DX chasing, and ensuring the antenna remains off the ground for agricultural clearance. The article provides specific measurements, such as the loop's height and feed point impedance, which are critical for optimizing performance. The use of NEC modeling software illustrates the importance of accurate resonance calculations, revealing how proximity to the tower affects both pattern and impedance. This practical account serves as a resource for hams looking to build effective antennas while navigating typical construction hurdles.

The most basic form of repeater receives communication on one frequency and re-transmits it on a different frequency, a process known as duplex communication. This capability significantly extends the range of handheld and mobile radios, as repeaters are typically situated at elevated locations with high-gain antennas and greater transmit power. Repeaters commonly operate with FM modulation on the VHF (30 MHz – 300 MHz) and UHF (300 MHz – 3 GHz) amateur bands, which are ideal for portable and mobile devices. Access to repeaters is often controlled by a CTCSS or PL tone, an inaudible signal that prevents the repeater from retransmitting background noise. This mechanism ensures efficient use of the frequency and prevents illegal continuous transmission. Canadian regulations, for instance, require an Advanced amateur radio license and an available frequency within the band to set up a repeater, each assigned a unique call sign and transmit frequency. Configuring a radio for repeater use involves knowing the repeater's transmit frequency, its receive frequency offset (e.g., -600 KHz for VHF or +5 MHz for UHF), and the necessary CTCSS tone. The article references resources like Repeater Book for locating repeaters and provides practical examples for initiating and concluding a basic repeater session, emphasizing clear identification and concise communication.