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A 20-meter window frame stealth antenna, based on a design by _PD7MAA_, utilizes a single 620cm wire loop for discreet installation. The feeding mechanism employs a _4C65_ toroidal core, where the antenna loop functions as a single-turn secondary, and the feedline wraps twice. Tuning is achieved via a 30cm twisted wire stub, allowing for SWR adjustment within the 20m band. This design is specified for QRP operation, with a maximum power limit of **25 Watts** to prevent core saturation or arcing. Wire selection recommendations include thin, insulated copper wire (0.75mm to 1mm) for blending with architectural elements. The guide focuses on practical construction steps for a low-profile 14MHz antenna.

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.

The Buddistick antenna, as demonstrated by KP4MD, effectively handles up to **250 watts** and provides coverage from 40 through 10 meters, with an optional coil extending operation to 80 and 60 meters. KP4MD's video presentation meticulously describes the antenna setup, emphasizing the critical role of the _shunting coil_ for achieving resonance on lower bands like 40 and 80 meters. This practical approach highlights how a compact antenna can deliver solid performance from a constrained location. SWR curve diagrams are included, clearly illustrating the impact of the shunting coil on the antenna's resonating frequency. These visual aids provide concrete evidence of the adjustments needed for optimal operation across different bands, particularly when space is at a premium. KP4MD's insights are particularly valuable for hams operating from apartments or other limited spaces, showcasing real-world results from a balcony installation.

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.

A homemade delta loop antenna for six meters band in German

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.

WiFi Antenna, WiFi Amplifier, RF Splitters, RF FIlters, Adapter, Video Cable and Custom Connectivity Products

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

When on the trail, at Field Day, or whenever a good antenna is unavailable, a random wire can save the day, but it is important to understand its properties.

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

Basic magnetic loop antenna examples and loop aerials theory explained. This article inclued some interesting tricks on building magnetic loop antennas and an usefull excell sheet to help compute magneti loop antennas calculating power efficiency from 10 to 40 meters band

On-line shop for coax cables, RF connectors, Lightning protectors, Create antenna rotators, antenna masts and mounts, amateur antennas by FlexaYagi, Tonna F9FT, ANjo-Antennen and M2 Antennas based in Eggolsheim Germany

Make them simple then Make them work. The LAZY H antenna is a general type of antenna that is in the curtain array family. By placing two 1 wavelength dipoles in a plane that is at right angles to the direction of maximum radiation and keeping the proper in-phase current condition to each element, you can achieve a high gain bi-directional antenna.

This page describes a comparison study on seven different beam antennas for 40 meters band. Yagi antennas, moxon antennas, mini horse all antennas are described with schema diagram , azimuth plot and SWR F/B Gain diagram

A Multiband Slinky Coil for the PAC-12 portable Antenna, can be used also as a dual PAC-12 dipole by James Bennett

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

The Tri-pole antenna, a clever modification of a standard dipole, allows for dual-band operation by integrating a third element. This design effectively shortens the overall dipole length by 10 to 20 percent, simplifying antenna rotation and offering a compact footprint. KK4OBI's article delves into the operational principles, using a 6 and 10-meter Tri-pole as a primary example, and provides comprehensive instructions for constructing any Tri-pole antenna within the 6 to 15-meter range. Key to the Tri-pole's performance is its off-center feed, necessitating a common mode choke at the feed point for optimal tuning and reduced noise. The author outlines a methodical approach to determining element dimensions, starting with a vertical element frequency calculated as 0.47 times the sum of the desired upper and lower band frequencies. This calculation, along with K-values derived from trend lines, guides the initial lengths for the horizontal arms, demonstrating how a 10m-6m Tri-pole can achieve a total horizontal length 78% shorter than a conventional 10-meter dipole. Tuning and balancing are critical, with the article detailing adjustments to arm lengths and the vertical element to achieve balanced SWR values, as validated through 4NEC2 simulations. Radiation patterns are analyzed at various elevations, showing gains around 5.7 dBi and favorable take-off angles for DX contacts. Construction details specify aluminum tubing dimensions, U-bolts, and an SO-239 connector, emphasizing the importance of a ferrite-based choke for wideband operation.

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

Manufacturer of amplifier for small magnetic and electric receiving wideband antennas, and variable delay line kit for active antenna phased arrays

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 homemade j-pole antenna for six meters band, designed to work on local repeaters, and working on the 52-53 MHz. Includes a list of needed materials and detailed description on assembling the copper tubes used to build this antenna.

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.

Introduction to homebrewing antenna, for AM FM band reception

A basic YAGI UDA online antenna calculator, accept as input frequency, number of elements, diameter of parasitic element and boom diameter. This online calculator will generate a basic design data including each element length and spacing.

With my present QTH a beam antenna is no option, but I wanted a multiband antenna which covered as many bands as possible. After some investigations I decided to put my money in the Cushcraft R-8.

A dual band vertical antenna for 160 and 80 meters band, on a 18m spiderbeam fiberglass pole. This vertical is a good compromise when you want good performance on these two low ham bands and don't have the space to install two seperate antennas.

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

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.

A Shielded Low Frequency Loop Antenna, allows Simultaneous Transmission and Reception at the Same Site.

The simple balcony vertical HF antenna made with plastic fishing pole. Just along the pole I install copper wire in 7 meter length. Then was installed ATU. It was used home brew tuner. For each band was used one counterpoise in length 0.8 x lambda/4

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

This article presents a comprehensive guide to constructing a multiband vertical wire antenna. The design features parallel wires for various bands, all connected to a single balun, ensuring ease of assembly and adjustment. Materials required include a fishing rod, PVC tubing, and inexpensive wire. The antenna is lightweight, cost-effective, and suitable for field use or as an additional home setup. Detailed instructions and diagrams are provided to facilitate successful construction and optimal performance across multiple frequencies.

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