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Design your VHF UHF Yagi antenna online, a JavaScript enhanced web page that implements the design of an antenna for 2m and 70cm bands. This page offers a streamlined experience for Yagi antenna design enthusiasts. It assumes prior knowledge of Yagi design principles, minimizing distractions with a user-friendly interface. Equipped with essential equations, it provides instant design feedback. Red font warnings indicate design limitations, ensuring practical results. Constraints include Gain (11.8-21.6 dBd) and Boom Length (2.2-39 wavelengths), with additional frequency-dependent restrictions noted in input fields.

Official MixW website where you can download latest version and options for MixW, a widely used multimode software suite for amateur radio operators. The website provides access to various versions of the core MixW application, including legacy releases like Mix 2.21 for MS DOS and more recent iterations up to MixW version 3.2.105. Users can also obtain essential add-ons such as the **Olivia** support DLL, **Q15X25** support DLL, contest DLLs, and serial port emulation drivers. Detailed instructions are provided for Olivia mode operation, emphasizing the critical need for sound card sample rate calibration to ensure proper decoding and signal placement within specific frequency grids to minimize QRM. The page also links to external resources for localized help files in Spanish, Italian, French, German, and Polish, catering to a global user base. An alternative download page by G3VFP is also listed. MixW supports new transceivers for CAT control, including Yaesu FT-991, FT-1200, FT-3000, and Icom IC-7100, IC-7300, IC-7410, IC-7851. It also features an online callbook via QRZ.com.

Superfast analyzer for audio and radio signals. Examining radio signals is the original idea of Analyzer2000. Simply connect the AF-output of your receiver to the input of your soundcard and see, what you hear. Use SSB and you will have a feeling like using an expensive IF panorama adapter. Support for this version has been discontinued.

Three live police scanner streams are offered, broadcasting twenty-four hours a day from San Diego County. KE6CBF, the site's operator, provides real-time communications from agencies like the San Diego Police Department (SDPD), San Diego Fire-Rescue Department (SDFD), Sheriff, California Highway Patrol (CHP), and Air Traffic Control (ATC). Beyond the live audio, the platform includes a community forum for scanner enthusiasts. It also provides resources such as FAQs, _10-43_ information pages, and police codes to assist listeners in understanding the transmissions. The site aims for high-quality streaming audio with minimal downtime, supported by user donations. Powered by technologies like PERL, mySQL, ICECAST, APACHE, and LINUX, the site is designed for optimal viewing at **1024 x 768** resolution or higher.

A 10-20 meters coverage delta loop antenna. After relocating, DL2HCB designed a multiband loop antenna to cover 10-20m with an open-wire feed for impedance matching and compact installation. Inspired by the mini-X-Q design, a modified 10m delta-loop was built, enhanced with a 1/4 wave shorted stub for 28 MHz using 450-ohm ladder line. The antenna delivers east-west broadside radiation and performs as a closed loop on other bands. Operational tests yielded strong European signals and successful DX contacts, including a 20m QRP QSO with FY/DJ0PJ.

The G5RV antenna, with an overall length of **31.10m (102ft)**, functions as a 3/2-wave on 20 meters when installed horizontally at 12m (39ft), exhibiting a resonant frequency of 14.150MHz and an approximate resistance of 80 ohms. Its 10.36m (34ft) stub line, designed as a 1/2-wave on 14.150MHz with a 0.97 velocity coefficient, acts as an impedance transformer across other bands, aiming for multiband operation without traps. On 20m and higher frequencies, the G5RV demonstrates improved gain compared to a standard dipole, attributed to the _collinear effect_ from multiple 1/2-waves along the wire. The original design sought a multiband solution for limited spaces, often requiring an Antenna Tuning Unit (ATU) for effective operation across bands like 80, 40, 30, and 20m, particularly with modern solid-state PAs. Variants, such as the F8CI modification, incorporate a 1/4 current balun at the stub line's base for symmetrical-to-asymmetrical transition, known as a _remote balun_. Proper flat-top or inverted-V installation is critical for maintaining symmetry and collinear gain, with inverted-V apex angles below 120° progressively diminishing higher-band performance.

The 160/80m coaxial receiving loop antennas are designed to enhance reception on the top bands while minimizing noise. These antennas are particularly beneficial for operators with limited space, as they can be constructed using lightweight materials, making them portable and easy to deploy. The standalone 80m loop has a diameter of approximately four feet, allowing for easy rotation and installation above existing VHF antennas. Over the years, many amateur radio operators have turned to loop antennas as a viable alternative to traditional beverage antennas. The design allows for significant noise reduction, especially when paired with a quality pre-amplifier. Experimentation with various configurations has led to the discovery that diamond-shaped loops provide optimal performance. Users have reported a noticeable improvement in signal quality, making these loops a valuable addition to any low-band DXing setup.

Homemade 40 through 6 meter HF portable multiband antenna, an aluminium antenna construction article, with plan, drawings and photos

Demonstrates the construction of **magnetic loop antennas**, detailing both multi-turn and single-turn designs. It covers a 30-inch diameter multi-turn loop for 80 meters, based on a February 1996 QST article, and an octagon single-turn loop made from 15mm copper tube with a 4.8-meter circumference, operating from 7 MHz to 14 MHz. The document also presents a smaller 800mm diameter loop for 14 MHz to 28 MHz, emphasizing the importance of high-voltage tuning capacitors. Covers the design and construction of custom **butterfly capacitors** and piston capacitors, including a split stator capacitor with 140 pF capacitance and a 6000 Volt rating, and a butterfly capacitor with 5-65 pF and 7200 Volt rating. It explains why butterfly capacitors are preferred over split stator types for high power applications due to lower losses and direct series connection of rotors, reducing resistive losses from wiper contacts. Material recommendations include clear PVC for plates and brass or stainless steel for non-magnetic hardware. Addresses practical considerations such as feeding the loop with a shielded 1/5 Faraday loop made from RG213 or RG8 coax, achieving VSWR 1.1 across bands, and optimizing its placement 180° from the capacitor. It also discusses mechanical joint resistance, dissimilar metal oxidation prevention using Vaseline, and a simple method for determining radiation angle with a TL-light tube. The guide includes diagrams for rotor, stator, and end plate construction.

MRP40, a successor to the well-regarded MRP37, offers robust Morse code decoding capabilities by processing analog audio signals via a sound card and displaying the decoded text on a computer monitor. My own field tests with similar sound card decoders confirm that the quality of the audio input and proper signal conditioning are paramount for achieving reliable decoding, especially with _weak signals_. The program also facilitates CW transmission, converting keyboard input into Morse code to key a transceiver, a feature I've found useful for practicing sending or for quick contest exchanges. Beyond its core CW functions, MRP40 incorporates a convenient mini-logbook, which automatically checks for prior contacts and allows for quick logging by double-clicking callsigns in the receive window. This integration streamlines the logging process, a significant advantage during busy operating sessions where every second counts. The software also generates Morse tones using the sound card, a handy utility for testing tone sequences or for basic code practice. Additionally, the suite includes a DTMF decoder and generator, which can be used for decoding telephone dial tones or data transmissions over amateur radio frequencies. It also features MF-TeleType, a sound card-based audio data modem for transmitting text via radio, utilizing a principle similar to DTMF for encoding and decoding, offering a simple method for digital text communication.

Make your own VHF/UHF folded dipoles from aluminium tubing. Learn tips for folding yagi, softening the tubing, bending jig and make all waterproofing

How to make the Super antenna. To build this antenna you need a lot that is at least 100 feet across. Antenna covers all bands 80-10 meters + 30, 17, 12 meter WARC Bands This antenna works as a Full Wave Loop on 80 Meters and also works as a 2 wavelength open loop or Bi-Square on the 40 Meter band

The Pfeiffer Maltese Quad Antenna System presents a unique approach to traditional quad antennas by utilizing a linear loading technique. This method effectively reduces the overall size of the antenna while maintaining its performance capabilities. Designed by Andrew Pfeiffer, the antenna's configuration resembles a Maltese cross, which not only enhances its structural integrity but also allows it to withstand challenging environmental conditions. This system is adaptable, offering various configurations from a 4-spreader Maltese Quad to a 16-spreader Maltese Quadruple-Cross, making it suitable for operators looking to optimize their setup without sacrificing efficiency. This antenna system is particularly versatile, covering multiple bands including 40, 20, 17, 12, and 10 meters. The design focuses on minimizing the physical footprint while ensuring effective signal transmission and reception. Amateur radio operators can benefit from the detailed plans available in the accompanying PDF, which outlines the construction process and specifications. Whether you're a seasoned DXer or a newcomer to the hobby, the Pfeiffer Maltese Quad Antenna System offers a practical solution for enhancing your station's capabilities.

Force 12 HF and VHF antennas, aluminim towers and masts for ham radio

The Little Stick antenna is an aluminium version of the Vertical Bazooka design which was made from coax.

The Cubical Quad antenna is a popular choice among amateur radio operators due to its robust design and excellent performance characteristics. This resource provides essential scaling formulas that help determine the lengths of the antenna elements and the necessary gamma match values for various frequencies. The design is adaptable, allowing operators to optimize for gain or front-to-back ratio by adjusting the spacing between elements. The accompanying Excel files facilitate precise calculations, making it easier for both beginners and experienced hams to construct their own Cubical Quad antennas. In addition to the design formulas, the resource includes practical insights from the author, who has successfully built and utilized these antennas in various field events. The document outlines the tuning process for achieving minimum VSWR, ensuring optimal performance. With detailed illustrations and performance data, this guide serves as a comprehensive reference for anyone looking to delve into Cubical Quad antenna construction and optimization, enhancing their amateur radio experience.

DXprop is a radiowave propagation forecast freeware for ham radio operators, permits to predict propagation on 12 frequencies. Use Minimuf 3.5 routine developped for US Navy. Available in French and English

Determining the actual need for an antenna tuner often hinges on the specific antenna and feed line configuration in use. While many hams believe a tuner is always essential, its primary role is to present a 50-ohm impedance to the transceiver, not to "tune" the antenna itself. For instance, a resonant dipole fed with _coaxial cable_ at its design frequency typically requires no tuner, as the feed line impedance closely matches the radio's output. However, operating a non-resonant antenna, or using a resonant antenna on multiple bands, frequently necessitates a tuner to manage high Standing Wave Ratio (SWR) on the feed line. The article clarifies that a tuner placed at the transceiver only matches the radio to the feed line, not the antenna to the feed line. For maximum efficiency with a non-resonant antenna, an _automatic antenna tuner_ (ATU) or a remote tuner placed at the antenna feed point is often more effective, minimizing losses in the feed line. The discussion also touches on the practical implications of SWR, noting that modern transceivers often fold back power at high SWR, making a tuner a practical necessity to achieve full output power, even if the antenna itself is not perfectly matched.

MININEC for Windows 14 is antenna modeling tool for the novice, student and hobbyist. Download the mininec setup files.

Details the construction and optimization of antenna systems for amateur radio satellite operations, focusing on practical, homebrew solutions for VHF/UHF bands. It covers building _groundplane antennas_ from salvaged materials, recycling old beam antennas into new configurations like a 2-meter crossed yagi, and constructing a 10-meter horizontal delta loop. The resource also explains antenna matching techniques, including folded dipole driven elements and quarter-wave transformers, along with the importance of accurate SWR measurements and minimizing coax loss. Demonstrates how to achieve a **1:1 SWR** by carefully trimming elements and adjusting radial angles on groundplane antennas. It provides insights into selecting appropriate coax and connectors, highlighting the benefits of Belden 9913 for low loss and the proper installation of _N-connectors_. The article also addresses RFI mitigation from computer birdies and presents a design for a silent triac antenna control circuit, offering practical solutions for common satellite station challenges.

Orbitron, a cardware application, provides robust satellite tracking capabilities for radio amateurs and visual observers alike. It leverages NORAD SGP4/SDP4 prediction models to accurately display satellite positions in real-time or simulation, accommodating up to 20,000 objects loaded from _TLE files_. The software includes an advanced search engine for satellite passes and _Iridium flares_, offering printable results for planning observations or QSO attempts. Sebastian Stoff's creation supports various visualization options, including a 'Nightlife' dark color scheme for nocturnal use, and integrates a database of cities and satellite frequencies. Users can synchronize their PC clock via NTP and update TLE data over HTTP, with ZIP support. The application also features rotor and radio control capabilities, either built-in or through user-defined drivers, which is particularly useful for automating antenna pointing during satellite passes. Its interface is designed for ease of use, making satellite tracking accessible even for beginners. First released in 2005, Orbitron 3.71 runs on Windows 9x/Me/2k/XP/2k3/Vista and can operate on Linux via _Wine emulation_, requiring minimal system resources. The software's precision relies on periodic TLE updates, especially for low-Earth orbit objects, to account for orbital decay and maneuvers by satellites like the ISS or Soyuz.

This article describes how to make a quadrifilar helix (QFH) antenna easily, from inexpensive materials: uPVC plumbing pipe and RG-58U co-axial cable. A low-cost, easy-to-build Quadrifilar Helix (QFH) antenna for weather satellite reception using uPVC plumbing pipe and RG-58U coaxial cable. Unlike traditional designs requiring copper pipe and plumbing skills, this approach enables construction with basic tools and minimal technical expertise. The antenna's shorter, wider proportions favor higher elevation angles, reducing interference from horizon-level pager transmitters. Electrical connections are simplified at the antenna's apex, with the coaxial cable forming the radiating elements. Testing demonstrated consistent signal strength throughout satellite passes, proving effective weather satellite reception is achievable without precision engineering to sub-millimeter tolerances.

It is very simple to build and you can tune it in your shack room

Build your own antenna for the 23cm band ( 1250Mhz - 1280Mc ) using some aluminium and this simple design.

Building a moxon antenna with aluminium tubes

The 80-meter loop antenna, measuring 86 meters (282 feet) of wire, effectively operates across 8 HF bands from 80 through 10 meters, despite its length being a compromise for specific bands. This design prioritizes a "low enough" SWR across multiple bands, aiming for lower SWR values on higher frequencies due to increased feedline losses. A 200-ohm feedpoint impedance provides a workable SWR on every band, with feedpoint impedances ranging from 100 ohms for lower bands to 300 ohms for higher bands. Radiation patterns for the 80-meter loop, mounted at 15 meters high, show a maximum gain of 7.6 dBi at a 90-degree takeoff angle on 80 meters, and up to 12.9 dBi at a 10-degree takeoff angle on 12 meters. This configuration supports regional contacts on 80 meters and provides good DX performance on higher bands. Practical construction notes emphasize using robust supports like trees, ensuring wire slack with _egg insulators_ for wind resilience, and employing an oversized 2 kW 4:1 _balun_ to safely handle higher SWR conditions, even with 100W transceivers. Feedline losses are minimized using _LMR-400_ coax or ladder line, with power transfer efficiency between 80% and 95%. Antenna simulations were performed using _xnec2c_, and the provided NEC file is compatible with other NEC2 derivatives. The antenna is tunable on 6 of 8 bands with an internal ATU and all 8 bands with an external autotuner like the LDG AT-200 Pro.

HF multiband mini delta compact and easy assembling antenna that cover from 20 to 10 meters by GM3VLB

QRP and Homebrew HAM Radio by DL2FI and DL7NIK QRP Made in Germany and more QRP Kits, qrp transceivers, accessories, mini keyers dealer for antennas, atu and more accessories

Examines the current geopolitical landscape of Armenia, offering detailed reports on regional developments and internal political discourse. The station, _Radio Azatutyun_, covers critical discussions such as the potential for conflict in September, with one source suggesting a "war is coming, it won't be delayed," alongside ongoing debates about Armenia-EU visa liberalization, which is projected to require "another 2-3 years" for completion. It also highlights the contentious rhetoric surrounding the Prime Minister's interactions with displaced persons from Artsakh. The resource delves into significant international relations, including discussions between Bayramov and Araghchi on regional situations, and Iran's denial of recent negotiations with the US. It also features updates on former President Trump's demands for an additional **$200 billion** for defense and his assertion that "regime change" in Iran is effectively underway. Further content includes analyses of drone attacks in Baku, the proposed new Constitution, and local issues such as the delayed reconstruction of Gyumri's central market and the persistent problem of Vanadzor's temporary kindergartens. The platform also hosts podcasts like "The Choice is Yours," exploring the reliability of pre-election polls.

The KJ5VW 20 Meter Mini Yagi by Gary R. Hanson, Austin, Texas

The Inverted L antenna is a versatile and efficient design suitable for small gardens, allowing amateur radio operators to operate on multiple bands. This project outlines the construction of a 5-band inverted L antenna, which can cover HF bands effectively. The design is particularly advantageous for those with limited space, as it requires minimal ground space while providing good performance. The antenna can be easily constructed using common materials, making it accessible for both beginners and experienced hams. In this guide, GM0ONX shares detailed instructions on how to build the inverted L antenna, including dimensions and tuning tips. The project emphasizes the importance of proper installation and grounding to ensure optimal performance. Additionally, it discusses the antenna's compatibility with various transceivers and the potential for portable operation. This resource is ideal for hams looking to enhance their station with a multiband antenna that performs well in limited space.

MM Antenna Analyzer by JE3HHT Makoto Mori based on the moment method, which was introduced in MININEC. Download MMANA Free from this page that offer download of basic version and link to the MMANA pro version.

Rigid Dipole antennas for 14 MHz band using PVC and Aluminium tubing

A 10-meter J-Pole antenna, detailed in QST February 1950, offers a straightforward solution for hams operating with restricted space. This design, originally presented by W1BLR, is a **half-wave radiator** fed by a quarter-wave matching stub, providing a low-angle radiation pattern beneficial for DX. The article describes building the antenna from readily available materials like copper pipe, emphasizing its simplicity and effectiveness for **single-band operation**. The J-Pole's inherent design provides a good impedance match to 50-ohm coaxial cable without the need for an external tuner, a significant advantage for portable or minimalist stations. Its nondirectional pattern ensures coverage in all directions, making it a versatile choice for general operating on the 28 MHz band. The construction plans are clear, allowing even those with basic workshop skills to assemble a functional antenna.

Calculations for determining the wind loading stress on an antenna mast. Link to a spreadsheet for calculating the mast bending stress based on wind speed and antenna cross sectional area.

A small transmitting loop antenna for 20 metres using a aluminium bicycle wheel rim.

How to make a wifi cantenna using a mini ravioli can

A **90-foot tall** top-loaded vertical antenna for the 160-meter band is detailed, constructed from aluminum irrigation tubing. The design incorporates four sets of four guy wires for structural stability, essential for an antenna of this physical size. This _monoband_ vertical is optimized for low-band operation, providing a robust solution for DXing and contesting on 1.8 MHz. The document includes specific construction methods for assembling the aluminum irrigation tubing sections and securing the guy wires. While a full NEC model is not explicitly provided, the physical dimensions and construction materials are sufficient for replication by experienced builders. The antenna's height and top-loading configuration are critical for achieving efficient radiation on 160 meters, particularly in minimizing ground losses.

This is a C-L-C type tuner with a reflected power indicator. Tuning is done for minimum reflected power.

Mobile Antennas, mini magnet antennas, handheld antennas, by Reuex industrial

The BV6 50 MHz Yagis resource details the construction of two distinct Yagi antenna designs for the 6-meter band, specifically a 1-wavelength (1wl) model and a 2.1-wavelength (2.1wl) model. The 1wl Yagi, with a boom length of 5.850m, achieves a gain of **9.4 dBd**, while the 2.1wl Yagi, spanning 12.90m, boasts a gain of **11.9 dBd**. These designs adhere to a proven methodology for optimizing current slope and maintaining constant phase delay across parasitic elements, ensuring high gain per boom length and an _excellent pattern_. Both designs target a 50-ohm input impedance, facilitating straightforward feeding with a robust folded dipole. Final verification using NEC-II software confirmed the antennas' exceptional stacking capabilities, yielding stacking gains exceeding **5.8 dB** for a 2x2 array with minimal mutual detuning. The resource provides common mechanical data, including boom and element diameters, and specifies element lengths corrected for boom diameter. While the original _DUBUS Technik V_ publication contained incorrect element lengths, this resource provides the accurate dimensions for proper construction, emphasizing the use of readily available materials for cost-effective amateur radio deployment.

A 40m through 17m Mini End Fed Half Wave Antenna Coupler by Steve Yates - AA5TB

The homemade CW paddle key design, inspired by a QRP homepage, utilizes soldered PC board material for its construction. The builder, DL5NEJ, modified an existing design to achieve a smaller footprint, preferring a compact setup for portable operations. This paddle was specifically built to complement a Wilderness Radio SST20 QRP transceiver kit, demonstrating its suitability for low-power operations. The project details suggest a straightforward assembly process, with the primary components being readily available PC board scraps. The design emphasizes simplicity and functionality, aiming to provide a reliable keying experience comparable to commercial paddles like the Bencher. Performance evaluations indicated the simple paddle operates effectively, prompting further exploration into similarly minimalist QRP rig designs. Additional construction details for a similar paddle are available from PA0CMU.

SP5DDJ mini antenna tuner for QRP operations

When one operates at low power on SSB, speech processing becomes almost essential to get through the QRM. The circuit is a low cost speech processor that will perform well with a minimum of construction effort.

Details a practical QRP wattmeter construction, leveraging a simplified SWR meter design by JA6HIC. The project focuses on a forward-only power measurement circuit, providing a functional instrument for RF power levels from milliwatts up to 5 watts. It maintains a 50-ohm input and output impedance, suitable for typical QRP transceivers and antenna systems. The resource includes the schematic for the "VSW" (Very Simple Wattmeter) and outlines a six-step alignment procedure. This calibration process involves using a known RF source up to 5W, setting full-scale deflection, and marking power increments. It also addresses minimizing frequency effects on readings with a 100pF trimmer capacitor, noting that measurement error is highest at the lower end of the scale. Construction notes mention using a piece of RG-213 coaxial cable for the inductance and coupler, with the wattmeter assembled in early 2003. The author provides an example measurement showing 0.8W into a dummy load and 1W into a 3-element beam.

The Buddipole website showcases a range of portable amateur radio antenna systems, including the **Buddipole**, Mini-Buddipole, Buddistick PRO, and BuddiHEX, designed for rapid deployment and multi-band operation from 40 meters to 2 meters. Each product page details specifications, operational modes (dipole or vertical), and compatible accessories like tripods, masts, and baluns. The site also features portable DC power management systems such as the PowerMini 2 and PowerPlus, which include integrated battery chargers and solar controllers, catering to off-grid or field day setups. Instructional videos demonstrate antenna assembly, tuning, and deployment techniques for various configurations, including the VersaTee vertical and Mini-Buddipole. Customer testimonials and DXpedition highlights, such as operations from Montserrat (VP2M) and Dominica (J38), provide real-world examples of the equipment's performance in challenging environments. The company, established in 2001, emphasizes modularity, versatility, and efficiency in its product line, all manufactured in the USA. Shipping information, a 30-day return policy with no restocking fee, and contact details for their Heber City, Utah facility are clearly presented. The site serves as a direct sales portal, offering a comprehensive catalog of antennas, power solutions, and components for portable amateur radio enthusiasts.

GNU Radio is a collection of software that when combined with minimal hardware, allows the construction of radios where the actual waveforms transmitted and received are defined by software

Tunes symmetric/coax/longwire antenna's between 1.8-50MHz

Approximately 400 kHz is the primary frequency for Navtex broadcasts, a crucial maritime safety information system. This legacy software, _Frisnit Navtex Decoder_ version 2.1.5, provides a means to decode these messages directly from an amateur radio receiver's audio output, fed into a PC's microphone input. It operates by processing the audio stream, extracting the FSK (Frequency Shift Keying) data, and presenting the decoded text on a Windows platform. Despite being unsupported and no longer under active development, the application remains functional across a wide range of Microsoft operating systems, from _Windows 95_ through _Windows 11_. Its utility lies in offering a straightforward, no-cost solution for hams and SWLs interested in monitoring Navtex transmissions without specialized hardware. The software's design focuses on simplicity, allowing users to quickly set up and begin decoding maritime weather forecasts, navigation warnings, and other safety-critical information. It leverages the PC's sound card, making it accessible with minimal additional equipment beyond a receiver capable of tuning to the Navtex frequencies.