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The ZS1J/B beacon operates on 28.2025 MHz with 5 Watts output to a half-wave, end-fed vertical antenna, initially installed in 1977 as ZS5VHF near Durban. The 10-meter transmitter is a modified 23-channel CB radio, and the identification keyer uses a diode matrix unit with TTL ICs from the same era. After relocation to Plettenberg Bay in 1993, the beacon has been in continuous service, with additional QRP transmitters later installed for other bands. In 1994, a single-transistor, 80-meter, 0.5-watt QRP transmitter with a half-wave dipole was added on 3586 kHz, followed by a 160-meter, 0.5-watt unit on 1817 kHz. A 30-meter, 0.5-watt transmitter was installed in 1996, operating on 10.124 MHz. In 2002, a 40-meter QRRP beacon on 7029 kHz, with an output of 100 microwatts, achieved DX reports up to 1100 km from ZS6UT in Pretoria. Best DX reports for the 80m and 160m beacons came from 9J2BO.

A top band shortened vertical antenna project. This project includes drawing and MMANA-GAL output screens.

The page provides information on a simple 50MHz J-Pole Antenna project based on the DK7ZB design. It explains the principle of the Wireman-J-Pole, the feeding process, practical mounting, and simulation results using MMANA GAL. The content aims to guide amateur radio operators in building their own J-Pole antennas for the 6-meter band.

Welcome to our line of Low Frequency, Natural Radio Research, Broadcast, Marine and Shortwave products. Our evolving product line is the result of our dedicated research efforts primarily in the areas of LF, VLF, MF, and HF.

Low-frequency (LF) radio time signals, operating primarily in the 40–80 kHz range, are broadcast by national physics laboratories for precise clock synchronization. Transmitters like **JJY** (40 kHz, 50 kW; 60 kHz, 50 kW), RTZ (50 kHz, 10 kW ERP), MSF (60 kHz, 15 kW ERP), WWVB (60 kHz, 50 kW ERP), RBU (66.66 kHz, 10 kW), and DCF77 (77.5 kHz, 50 kW) cover vast geographic areas, often several hundred to thousands of kilometers. LF signals offer distinct propagation advantages over higher-band transmissions such as GPS. Their long wavelengths (3–6 km) enable effective diffraction around obstacles like mountains and buildings. The ionosphere and ground act as a waveguide, eliminating the need for line-of-sight and allowing a single powerful station to cover extensive regions. Ground wave propagation minimizes ionospheric variability effects on transmission delay, and signals penetrate most building walls effectively. Robust and low-cost receivers, often priced at 20–30 USD/EUR, are widely used in radio clocks. These receivers typically comprise a tuned ferrite core antenna, a receiver IC (e.g., Atmel T4227, U4223B, MAS1016) for amplification and AM detection, and a microcontroller for decoding the time signal and phase-locking a local clock. Specific components for DCF77, MSF, and WWVB are readily available from vendors like HKW Elektronik and Ultralink.

Free ham radio utilities written in LabVIEW includes Open Wire Calculator, Dipole Peak/Null Angle Calculator, a Coil-Shortened Antenna Calculator ad interesting Round Coil Inductance Calculator and a Skyloop Antenna Calculator

Meet The Breakers is a unique exploration of the CB radio culture in the United Kingdom, hosted by Colin The Head. This series delves into the lives of various CB radio enthusiasts, showcasing their setups, stories, and the vibrant community surrounding this hobby. Each episode features interviews with notable figures in the CB world, providing insights into their experiences and the equipment they use. The program not only highlights the technical aspects of CB radio, such as antennas and signal checks, but also captures the personal stories that make this hobby special. From collectors of rare equipment to modern-day users navigating the airwaves, Meet The Breakers offers a comprehensive look at the diverse personalities that contribute to the CB radio landscape in the UK. Whether you're a seasoned operator or new to the scene, this series is a valuable resource for anyone interested in the world of CB radio.

Operating an amateur radio club, VE2CEV details its activities, including regular meetings and a significant project involving the construction of a **satellite ground station**. The resource outlines the project's inception, team formation, equipment acquisition, and the physical installation of antennas and rotator systems. It specifically mentions the use of a dual-axis AZ/EL rotator and antennas for VHF, UHF, and SHF (2 meters, 70 centimeters, and 13 centimeters), along with the strategic use of **Heliax cables** to minimize RF signal loss. The club also provides information on its interconnected repeater network covering southwestern Montérégie. The content highlights the practical application of the satellite station for communicating via amateur satellites and the International Space Station (ISS). It details the collaborative effort of members in securing a powerful Linux server, negotiating antenna installation with local authorities, and the precise alignment of antennas. The club emphasizes its role in guiding new amateurs, offering demonstrations, and potentially organizing courses, indicating a focus on community engagement and technical education within the amateur radio hobby.

Australian antenna manufacturer, Mobile 1 CB Radio Antennas, Mobile Phone Antennas 3G, NextG, EDGE Digital Radio & TV Antennas Broadcast Band Antennas Airband Antennas Amateur Band Antennas Scanner Antennas Commercial Antennas

On December 12, 1901, Guglielmo Marconi successfully received the first transatlantic wireless communication, a Morse code "S" (three dots), at 04:30 GMT. This article details the setup for this groundbreaking experiment, noting Marconi's receiver in St. John’s, Newfoundland, Canada, utilized a _coherer_ and an antenna elevated by balloons and kites. The transmitting station at Poldhu, Cornwall, England, featured twenty-four 200-foot ships' masts and a 25-kilowatt alternator. The resource explains how this contact disproved contemporary beliefs about radio wave limitations due to Earth's curvature, later understood through _ionospheric propagation_. It frames Marconi's achievement as the "very first DX" in amateur radio terms, defining DX as telegraphic shorthand for distance and _DXing_ as the hobby of receiving distant signals. The article also provides external links for further reading on Marconi's experiments and the science behind transatlantic radio signal reception.

This project is a full wavelength, horizontal, loop antenna for the 40 metre Amateur Radio band, built using insulated copper wire in a diamond shape, supported by egg insulators, tethered to 4 masts, each 6.5m high

This is a project aboout compact and portable a QRP antenna tuner for use in the HF ham radio bands from 3-30 MHz, even if it's a compact and efficient project this small antenna tuner will not match any possible load.

NJ2X is a licensed amateur radio operator (FCC Amateur Extra) who enjoys casting electromagnetic waves into the ether. NJ2X pursues many aspects of the hobby including chasing DX, participating in mini-DX expeditions, building equipment and antennas, and papering his shack walls with ARRL awards. NJ2X dedicates this amateur radio oriented site to helping others who also enjoy the greatest of scientific hobbies. The site is suitable for all readers - families, the young, and the young at heart.

Thsi article describes a microcontroller driven semi-automatic antenna tuner capable of handling power levels up to 150 watts. The device is a low pass filter tuner manually tuned by setting the optimized L/C combination by hand and then storing the values into the EEPROM of the mictrocontroller to recall them later (seperately for each band from 80 to 10 meters including WARC bands)

Scan Antenna supply precision antennas to some of the world’s most advanced, market leading companies. Their antennas fit in satellite voice/data, mobile/wireless GSM, GPS, marine/land based radio and other specialty systems.

TIM-CO, an authorized distributor, offers a range of electronic components crucial for various applications, including amateur radio station builds. Their inventory focuses on **connectors**, both commercial and military-grade, which are essential for robust and reliable interconnections in radio equipment and antenna systems. This includes a variety of types suitable for RF applications, ensuring signal integrity. Beyond connectors, TIM-CO provides passive and electromechanical components, fundamental building blocks for any radio circuit or control system. These components are vital for constructing filters, impedance matching networks, and power distribution systems within a shack. Their selection supports both new construction and repair of existing gear. Additionally, the company supplies **RF-coax cable assemblies**, pre-fabricated solutions that save time and ensure proper termination for feedlines and inter-component connections. These assemblies are critical for minimizing signal loss and maintaining impedance matching from the transceiver to the antenna.

The G5O Contest Group blog documents contest operations and related activities of the Stockport Radio Society. It covers various **HF** and **VHF** contests, providing insights into station setup, antenna configurations, and operational strategies employed during events. The content frequently includes post-contest analyses, discussing scores, propagation conditions, and technical challenges encountered. The blog entries detail specific contest participations, often featuring photographs of the operating environment and equipment used. It serves as a chronicle of the group's contesting history, offering practical examples of multi-operator station management and logistical planning for competitive amateur radio events. The group's focus on both local and international contests is evident through the range of events covered. Regular updates provide a continuous record of the group's engagement in the amateur radio contesting community.

Amateur Radio Station N1UL/mm Ulrich L. Rohde, includes a maritime mobile antenna shack

An interesting article on end fed half-wave wire antennas with a couple of original experiments. Author illustrate the role of the QRP matchbox, and a 40/20 meter antenna with a center stub making it a large bandwidth antenna for 40 and 20. Includes also an 80/40 end fed with the typical coil to make it available on 80 merts band.

Sommer Antennas has been a manufacturer and producer of quality amateur radio antennas and antennas for professional use for more than 20 years.Developed by DJ2UT in Germany, our beams were first introduced to the U.S. market at the 1984 Dayton Hamvention

This article presents an innovative homebrew antenna design utilizing surplus ladder line as a receiving antenna for HF and MF bands. The Ladder Line Antenna (LLA) transforms standard 450-ohm ladder line into a directional, bidirectional, or omnidirectional antenna system through different termination methods. The design, which requires minimal space and height, achieves 6-10dB front-to-back ratio on 40-160m bands using a 33-foot length. This DIY wire antenna project offers an efficient, low-profile solution for amateur radio operators, featuring broadband operation without ground radials and easy installation below fence height.

New generation Hex Beam Antennas. VHQ HEX Products, located in Peterborough, NH, is owned and operated by David M. Lavoie. Our products are designed to solve issues encountered in Ham radio applications and move with todays configurations in an ever changing climate

M0AUW's Amateur Radio blog specialising in Cobweb and Moxon antennas

The structure of this dual band VHF UHF antenna is very simple. It consists of two identical square loops, whose sides measure a quarter wave, connected together at the ends. A project by I5NZR

Dipole antennas are some of the simplest antennas to build in addition to being very efficient and solid performers. I wanted to make a simple dipole antenna for QRP portable operation that could be used on multiple bands.

A portable setup of the ICOM IC-705 with portable VHF UHF and and HF Alex Loop antenna, managed with a portable Raspberry PI 3 setup.

Antennas for Amateur Radio and short wave listening

High Speed Multimedia (HSMM) radio, as introduced by John Champa, K8OCL, represents a significant advancement in amateur radio's digital capabilities, moving beyond traditional keyboard modes like packet radio. This initiative, driven by ARRL's Technology Task Force, focuses on developing high-speed digital radio networks capable of up to 20 megabits per second. HSMM primarily facilitates digital voice (DV) and digital video (ADV), enabling real-time video transmission from emergency scenes to an EOC without expensive ATV gear, often requiring only a laptop, a PCMCIA card, a digital camera, and a small antenna. The working group's initial efforts concentrate on cultivating microwave skills within the amateur community to build and support portable and fixed high-speed radio-based local networking, or **RLANs**. These networks prove invaluable for RACES and ARES organizations, as well as homeland security and other emergency communications. Field Day exercises and simulated emergency tests (SETs) are encouraged to hone skills in rapid site surveys and deploying broadband HSMM microwave radio networks, with examples like linking Field Day logging stations or antenna test results at the Midwest VHF-UHF Society Picnic 2003. Getting started with HSMM often involves adapting off-the-shelf **IEEE 802.11** (WiFi) equipment to comply with amateur radio regulations, typically operating in the 2.4 GHz ISM bands. While consumer WiFi gear has range limitations under Part 15 rules, proper setup under amateur regulations can extend coverage significantly, with test networks like the Hinternet achieving 5-15 mile ranges at 54 M bit/s using small mast-mounted dish antennas. Careful selection of equipment with external antenna ports, high transmit power, and low receive sensitivity is crucial, along with using low-loss coaxial cable like LMR-400 for optimal performance at these frequencies.

Amateur radio loop antenna project using a Comet CVBA-500BC vacuum variable capacitor.

Antenna Analyzer plus 500 is a multifunctional measuring instrument, very useful for amateur radio activity. Its size allows you to easily take it for relocation as well. Frequency range: 100KHz - 500MHz. Access directly via WiFi. Includes a dual-channel signal generator

Manufacturer of software definded radio receivers, antenna switches, preselectors, antenna splitters based in Italy and USA

Presents amateur radio activities and experiences from JJ0LUU and JJ0LXF, two operators based in Japan. The weblog, hosted on shinshu.fm, documents their on-air operations, equipment setups, and general ham radio interests. Content often includes details about specific contacts, antenna configurations, and local operating conditions within the Japanese amateur radio community. The resource primarily focuses on personal operating logs and occasional technical discussions relevant to their station. It offers a glimpse into the daily life and pursuits of Japanese **amateur radio** operators, detailing their engagement with various bands and modes. JJ0LUU and JJ0LXF share their passion for radio communication, contributing to the broader online repository of individual ham radio narratives. The site serves as a digital logbook and informal platform for sharing their **DXing** and contesting endeavors.

For every radio amateur who loves to travel by car, a mobile installation soon becomes a necessity. While in inhabited areas there is usually some coverage of VHF repeaters, in many other places VHF radios are useless. In these very places, HF can provide reliable contacts, and a lot of fun, from anywhere.

Operating in a Single Operator Two Radios (SO2R) setup, especially with beverage antennas, often exposes the receiving radio's front-end to significant RF energy from the transmitting radio. This resource details a practical, homebrew receiver protection circuit designed to mitigate this risk. The core of the design involves a non-inductive 2W 22 Ohm carbon composition resistor in series with the RX antenna line, followed by two stacks of four fast-switching diodes (e.g., _1N914_) configured in opposite polarizations. This arrangement effectively clamps the incoming voltage to approximately 2.8 V peak-to-peak, safeguarding sensitive receiver input components. The series resistor plays a crucial role by absorbing excess power, preventing the diodes from exceeding their current ratings and potentially failing open, which would leave the receiver unprotected. The author, _N4KG_, measured up to 50 watts of coupled power between 80M slopers on the same tower, highlighting the necessity of such protection. The design is presented as a cost-effective solution to prevent damage to receiver input transformers, with the author noting successful protection of a receiver even after a resistor showed signs of overheating. This simple circuit can be integrated via a transverter plug, offering a robust defense against high RF input.

Voldatech, a manufacturer based in China, produces a range of RF feeder cables and site components essential for amateur radio installations and telecommunication infrastructure. Their product line includes various types of coaxial cables, such as **50 Ohm** and 75 Ohm options, along with a comprehensive selection of connectors like N-type, UHF, and BNC. These components are critical for maintaining signal integrity and minimizing loss in antenna systems, whether for a home shack or a remote DXpedition setup. The company's focus on _RF Coax cables_ and connectors directly supports the needs of radio amateurs seeking reliable transmission lines for their transceivers and antennas. Amateurs often compare Voldatech's offerings to established brands, evaluating factors such as impedance matching, shielding effectiveness, and durability under various environmental conditions. The availability of diverse cable types allows operators to select optimal solutions for different frequency bands and power levels, from QRP to high-power amplifier setups. Their products are particularly relevant for those constructing new antenna arrays or upgrading existing feedline systems, aiming to achieve maximum power transfer and reduce standing wave ratio (SWR) for efficient signal propagation.

This page provides a detailed guide on the Guanella Current Balun for ham radio operators. The author shares very nice schematics, photos, and explanations on the construction and use of this type of balun. The content explains when a balun is needed and how it can help with common-mode currents in antenna systems. It also discusses the construction process, including winding the balun around a ferrite core. This resource is useful for hams looking to improve their antenna systems and reduce common-mode currents for better performance. This article is in Dutch.

DF0WD/DL4YHF's Longwave Overview details amateur radio operations on the 135.7 to 137.8 kHz segment in Germany. The author outlines the "inofficial" European band plan, specifying segments for QRSS, TX tests, beacons, conventional CW, and data modes. Early LF activities at DF0WD began with a 20-watt CW transmitter, later upgraded to a homemade linear transverter capable of 100 watts, driven by an Icom IC706 on 10.137 MHz. The station's antenna system includes a 200-meter wire, approximately 10 meters above ground, supported by football field light-masts. Despite its length, the antenna's efficiency is noted as very low due to the immense wavelength of about 2.2 km. The author's experience highlights the significant challenge of achieving effective radiated power (EIRP) on LF, estimating DF0WD's EIRP at around 80 milliwatts based on field strength measurements from PA0SE. DF0WD/DL4YHF has successfully worked numerous countries on 136 kHz CW, including DL, F, G, GI, GM, GU, GW, HB9, HB0, LX, OE, OH, OK, OM, ON, OZ, PA, and SM. The author also mentions ongoing efforts to log contacts with CT, EI, LA/LG, and to complete a two-way QSO with Italy, demonstrating persistent activity on this challenging band.

MARCA, Inc. operates approximately 24 repeaters across Arizona mountaintops and Phoenix-area rooftops, supporting modes like D-STAR and Fusion. The club, holding the **W7MOT** callsign, engages in diverse activities including ARRL Field Day events near Forest Lakes, AZ, ARRL FMT contests, and antenna experimentation. Members actively participate in HF operations such as voice, digital, CW, DXing, and various digital HF modes, alongside MESH and EOC operations within the valley. The club's interests span a broad technical spectrum, from SDR radio building to antique radio restoration, and include modern digital modes like WSPR, WSJT, FT8, and FT4. They also explore computer-based operations such as Echolink, fostering a dedicated Single Board Computer (SBC) and Raspberry Pi group. Monthly VE testing sessions for Technician, General, and Extra Class licenses are conducted by Ray Vasquez, K4RMV. Meetings are held on the third Tuesday of each month, typically lasting two hours, with a business segment followed by a technical presentation. These gatherings occur in-person at IHop in Mesa, AZ, and concurrently via Zoom, accommodating both local members and winter visitors. Informal chat groups often form post-meeting to discuss specialized topics like D-STAR, SDR, APRS, MESH, and Fusion.

Ultimax antennas manufacturer of amateur radio End-Fed and bazooka antennas made in USA

Personal blog devoted to ham radio topics, portable operation, homebrew, antenna and other projects

Amateur Radio Amateur Radio Manuals & Books Computer Books & Programs Computer Hardware Rare & Hard to Find Books amateur radio,electronics ,electronis parts,tubes, amplifiers,towners, beam antennas and more

Wireless Society of Southern Maine Projects, instructions and photos for many ham radio projects and experiments, including antenna construction and modelling, kit building, station setup, restoration and more

The DIY 137 MHz WX SAT V-dipole antenna project details the construction of a specialized antenna for receiving weather satellite transmissions. It provides specific dimensions for the dipole elements, designed for optimal reception around the 137 MHz band, which is commonly used by NOAA and Meteor weather satellites. The resource outlines the materials required, such as aluminum tubing for elements and PVC for the support structure, along with the necessary coaxial cable and connectors. The article presents a clear, step-by-step assembly process, including how to form the V-shape and connect the feedline. It emphasizes practical considerations for mounting and weatherproofing the antenna for outdoor deployment. The design focuses on simplicity and effectiveness for amateur radio operators interested in satellite imagery. Key aspects include the precise angle of the V-dipole and the lengths of the radiating elements, which are critical for achieving the desired circular polarization response for satellite signals. The resource includes photographic documentation of the construction phases and the final mounted antenna.

The Terminated End Fed Vee Antenna (TEFV) is a travelling wave antenna with constant current distribution. Unlike traditional resonant antennas, TEFV operates without standing waves, using a terminating resistor for broadband efficiency. With a combination of vertical and horizontal polarization, it offers wide bandwidth from 1.8 MHz to 30 MHz, eliminating the need for a tuner. Key components include a 9:1 unun transformer and a 500-ohm terminating resistor. Grounding and counterpoise enhance performance, and it can handle power losses of up to 30%. TEFV provides an effective, versatile antenna solution for amateur radio and broadcast applications.

Online coloured Azimuthal Map Generator. By default, this map shows the current gray line. The parts of the Earth that are currently in the sun (i.e., daytime) appear brighter, and the parts of the Earth that are experiencing night appear darker

This article is about a homebrew 6 meter lightweight Moxon antenna. Article includes a full part list, instruction to assemble the parts and pictures.

Documents S21RC's construction of an impedance transformer harness for a VHF/UHF cross yagi, utilizing 20m of _RG179_ cable. Details the creation of a DIY RF sampler with a -50dB sampling output, primarily for measuring HF radio PA section output with a Spectrum Analyzer, also applicable for _Pure Signal_ transmission. Chronicles the deployment of a 200m long beverage antenna for the _S21DX IOTA_ operation in 2022, positioned 2m above ground. Discusses the construction of a 3-element short beam for 10m to replace a previous 2-element antenna, with assistance from S21DW. Provides guidance on operating cheap _PA-70_ and _PA-100_ type Chinese SSPAs using IRF530 MOSFETs, emphasizing the necessity of a final LPF. Outlines the design and construction of a fully isolated interface for radio-to-computer connections, supporting various digital modes with isolated ground, audio transformers for IN/OUT, optical isolation for CAT/CIV, and isolated PTT/COS lines. Includes a log of software updates, such as the _HMI/TFT for NX8048K070_ and _2.1.14 Lite_ release with bug fixes for PEP hold and gradual watt decay.

Polish Online radio shop, dealer for President Alan Midland CBradia CRE Magnum Intek Yosan CRT Firestik Antenna Sirio Solarcon

The club was founded in 1987 when a group of ham operators hauled radio gear, antennas, and a generator to the island by boat to operate portable during ARRL Field Day

Over 500 different types of high-performance electronic cables are manufactured by Alpha Wire, catering to demanding industrial and commercial applications. Their product lines include the robust _XTRA GUARD_ series, designed for harsh environments, and a range of flexible coaxial cables optimized for signal integrity. These cables are critical components in amateur radio shacks, industrial control systems, and data communication networks, ensuring reliable power and signal transmission. The company provides extensive technical resources, including detailed product specifications, application notes, and RoHS certificates, accessible through their online resource center. Hams often utilize their wire and cable products for antenna construction, station wiring, and various DIY projects requiring durable and reliable conductors. Alpha Wire also offers tools like size guides and competitor cross-references, simplifying product selection. They emphasize continuous uptime solutions, reflecting their focus on quality and durability.