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Undestanding and measuring SWR, Standing Wave Ratio in antenna feed lines. This article also introduce basic concepts and usage guidelines of amateur radio antenna tuners

Collection of several topics on antenna tuners and their performance. Why use an antenna tuner? How does an antenna tuner…tune Does an antenna tuner fool the radio? Will an antenna tuner waste power? Can an antenna tuner help get more power to the antenna?

Antennas custom made to your frequency of choice

If You are using a separate receive antennas then you need a good protection circuit to eliminate the possibility of blowing out the receiver front-end while using these auxiliary receive antennas specially on low bands.

A light portable 2 element Delta beam antenna for 14 MHz. It is basically a two element delta loop wire antenna made for portable usage providing good directivity and a 4.2 dBd gain

Have you ever thought of setting up a portable HF station for an activity like the Field Day ?

How to solve RFI problems caused by the charge controller, which is a PWM type charge controller, that generates a lot of EMI interference

An end fed antenna winder design that also contains the necessary matching toroid. This would be just the thing to throw in your backpack for portable operation.

A 3 band dipole antenna for 40-80-160 meter bands, It's made with easily available materials and is designed for inverted V mounting. The antenna is shortened for these bands, but still manages to make contacts in 80m and 160m with stations in Canada and the USA. The construction details are provided, including the dimensions of the antenna elements and the traps. The antenna is easy to build and provides good performance in all three bands. In Italian.

Examines various low-band receiving antennas, including the Beverage, Pennant, Flag, and Quad, specifically for deployment in noisy city environments. The resource provides a semi-scientific analysis of common receiving antenna types, focusing on their performance characteristics and practical considerations for urban settings. It details construction parameters for each antenna, such as the use of 9:1 baluns and 300-500 Ohm terminating resistors, and discusses the necessity of preamplifiers for certain configurations. Specific deployment advice includes avoiding radial fields to minimize noise pickup and methods for temporary wire antenna installations. The document provides antenna dimensions, noting a full-size Quad requires 540 feet of wire. Performance observations highlight a Quad variant used by N0XA (AB0X) that achieved 160M CQ WW records and facilitated over 120 JA contacts without a preamp.

A project about reversible unidirectional Beverage antennas plus a remote switching system conveniently controlled by the operator

A multiple page article about assembling the antenna system, this section includes informations on constructing of the concrete tower base, starting from setting up correctly the foundations in relation to the antenna height.

Construction tips of a basic wire antenna, the half wave dipole. Inverted V dipoles and effects of inverted v on radiation pattern.

This PDF guide provides detailed instructions and diagrams for constructing a fan dipole antenna, a popular choice among hams for multiband operations. The guide covers the design, materials needed, and installation process, offering step-by-step guidance to help hams set up an effective antenna system for their radio operations.

Operating in antenna-restricted communities presents unique challenges for amateur radio operators, often necessitating creative solutions for antenna deployment. This resource details the design and implementation of stealth antennas within a townhouse community in Exton, PA, where external antennas were strictly forbidden by covenants. The author, WB5NHL, describes his setup, which involved locating the shack in the basement and utilizing an unused space under the roofline of a finished third-floor loft for antenna placement. The content specifically addresses the practicalities of routing coax cables three floors and maximizing antenna performance within limited attic space. It covers solutions for multi-band operation, including dedicated sections for 40-10 meter and 80-meter antennas, along with strategies for mitigating potential interference issues. The approach emphasizes full compliance with community covenants, achieving maximum height-above-ground for horizontal antennas, enabling instant band switching, and efficiently utilizing available attic volume. While acknowledging limitations such as potential interference with high power and fixed antenna patterns, the resource provides a detailed account of a functional compromise for restricted environments. Links to individual pages on _coax cables_, _40-10 meter antennas_, _80-meter antennas_, and _interference issues_ offer deeper dives into each specific aspect of the installation.

DL7JV shares his practical experience building and testing capacitive antennas, initially skeptical of their performance compared to magnetic loops and mono-band dipoles. His interest was piqued after hearing a Spanish station running 100 Watts on 80 meters with a 1-meter Micro Vert, making DX contacts into PY and UA0, despite the antenna being only 4 meters high in a garden. This prompted DL7JV to investigate further, consulting resources from DL7PE and DL7AHW, the latter providing DOS programs like "Mitspule.exe" and "Spulenprg.zip" for calculating antenna dimensions and coil conversions. The article outlines the construction of two prototype antennas: one for 7.050 MHz using a 75mm PVC pipe and another for 3.550 MHz with a 110mm PVC pipe. Both designs feature aluminum foil condensers and coils wound from 1mm² H07V-K wire. DL7JV provides specific measurements for the condenser capacitance, surface area, diameter, height, coil inductance, turns, and wire length for both 40m and 80m versions, along with RG58 feedline lengths. Initial reception tests for the 7 MHz antenna, placed indoors, yielded impressive S9+5 signals from a German station compared to an S8 from a 42-meter roof-mounted loop, even hearing a Japanese station. Transmission attempts on April 4, 2004, despite moderate solar storm conditions, resulted in successful QSOs on 7 MHz with EA5OT (579/559) and on 3.5 MHz with YT1NT (579/559) and G4KKI (579/559) using 100 Watts. DL7JV notes the antenna's sensitivity to coordination and feedline layout, suggesting a modification from DL7AXO involving a 500pF fixed capacitor and coil tap for improved SWR stability. He concludes that while the capacitive antenna is space-saving and performs well for reception and 100W transmission indoors, its transmit performance doesn't yet match larger antennas, with further outdoor field tests planned. DL7JV also intends to build a 1.8 MHz version.

10 Elements Cross-Yagi Antenna for 433 MHz. The base of the 10el antenna is the recalculated RA6FOO antenna.Circular polarization is realized - by a phasing quarter-wave line, matching of horizontal and vertical polarization antennas

A vertical antenna for 160 meters band based on the K6MM vertical with some enhancements and modifications on the main capacitance hat

The Bazooka antenna, a coaxial dipole, functions as an omnidirectional antenna with vertical or horizontal polarization. Patented in 1939 and refined in 2006, it features a quarter-wavelength coaxial cable with separated conductors. The outer conductor connects to a sleeve, while the inner conductor extends vertically. Initially complex, it has been simplified for versatile use, including military applications. Adding elements can modify its behavior for NVIS or Yagi-Uda configurations. Experiments in 2007 at the Campus de Pesquisas Geofísicas in Paula Freitas-PR demonstrated consistent VHF and UHF performance, showing reliable return loss measurements despite variable weather.

This article discusses the Disk-Yagi antenna, also known as the "gun antenna," popularized by the video blogger KREOSAN. It explains the design, differences from standard Yagi-Uda antennas, and key features like the use of patch antennas and the integration of MIMO technology. The article covers the construction, tuning challenges, scaling issues, and provides insights on practical applications, such as optimizing signal performance with a 75-ohm antenna. It emphasizes that while DIY versions may vary, careful tuning and design are crucial for effectiveness.

Learn how to build a simple 12vdc azimuth and elevation motor unit for the Arrow Satellite Antenna to improve your FM satellite communication experience. This DIY project involves using a camera tripod and basic materials like aluminum tube and standoffs. Get detailed instructions, including the gearhead motor product number for optimal performance. Discover where to purchase the necessary components and stay updated on alternative motor options. Enhance your ham radio operations with this homemade rotator setup, designed for easy satellite tracking and communication. Share feedback and connect with other radio enthusiasts for more tips and ideas.

This Field Day Vertical Antenna project is the result of many years of attending various field day sites and realizing that what was needed is a simple, easy to assemble vertical antenna. The design of this Field Day Antenna is not very novel and leverages ideas from Butternut verticals and ARRL publications. The one essential requirement was that the antenna can be raised by just one person. The design of this Field Day Antenna is an above ground mounted ground plane vertical.

Installation and modification of the popular Butternut HF9V antenna with the optional 160 meter addon. Article includes a modification to improve the performance on the top band

For my SOTA activities, i recently bought a QRP transceiver QRP SW-3B, which is a three-band QRP CW only for 40/30/20 m. So, i needed an antenna that would allow to use these 3 bands in SOTA portable activity. Already having some experience with the EFHW antenna, i decided to build one for 40/30/20m.

Jeri Ellsworthhas started a video series devoted to building a magnetic loop antenna for the 160- and 80-meter bands. The first video, included after the break, is an overview of the rationale behind a magnetic loop

On the field comparison among C-Pole antenna, an EFHW vertical antenna and an Inverter V dipole antenna. Test is done using two identical WSPRLite beacons that transmit with 200mW on the WSPR frequency and analyzing spotted results.

This 10 meter antenna is right out of the ARRL Antenna Book. There are 5 elements on a 24 feet boom and it performs well from 28.0 to 28.9 MHz.

With this antenna the coverage is 80,40,20,15 and 10 meter band without any antenna tuner and the average SWR is below 1.2 on phone bands. The total antenna lenght is about 23 meters , with one 20.4 meters long segment from the 1:49 transformer to the 110uh coil and about 2.2 meters long segment from the coil to the insulator.

Despite the model limitations, such as a single TXRX antenna connector, the author shares a reversible modification involving a coax relay for enhanced functionality, demonstrating the transceiver's adaptability and customization potential.

A QST Article published in November 1922 is about the origin of Beverage antennas, an unidirectional antenna type that was discovered and experimented for the first time in that period. This article is the introduction to beverage antenna theory, by the homonimous autho H. H. Beverage.

A distance of 1/8 lambda between the antenna and the vehicle roof is suggested for optimal performance, with slight adjustments possible to lower the take-off angle for terrestrial contacts. This resource details the adaptation of an _Eggbeater_ antenna for mobile use, specifically for VHF operation, leveraging the car's metal roof as a ground plane. It illustrates the mounting method, repurposing a magnetic ski carrier base, and describes the integration of coaxial relays for polarization reversal, a feature also applicable to UHF versions as discussed in "_Eggbeater Antenna VHF/UHF – Part 2_". This mobile configuration proves effective for satellite communications, such as through the International Space Station (ISS), while also maintaining strong performance for land-based radio contacts. The inclusion of switches with indicator lights for VHF and UHF polarization control, powered by the vehicle's battery, highlights practical considerations for field deployment. The system's adaptability for portable operations underscores its versatility beyond fixed mobile installations.

The collinear J-Pole, often known as the Super-J, does improve the behavior over a regular J-Pole. there is an advantage when vertically combining 1/2 radiating sections to have a bit of separation between the half-wave end points. Get 0.8 dB more gain out of the trusty Super-J by replacing the traditional phasing stub with a long coil.

This is a very small vertical 160m antenna that fits in the loft of even my small house. It was built as a way of getting a signal out on 160m for local AM contacts, but the local noise level was far too high to allow it to be used at night for this purpose. However, on WSPR it did a pretty good job with WSPR spots from a very long way across Europe being received when running 2.5W out.

This unique online tool helps Ham Radio operators to choose the right rotator for medium and large HF antenna systems. The algorithm implemented in this calculator is the result of 40 years of experience in the HF Antenna sector. Given the Wind Speed, the total antenna square area, and the boom length, it will return the calculated torque value.

This active antenna for the shortwave band provides surprising performance, even indoors. As the name implies, the main loop is made from a Hula-Hoop with the metallic paint stripped off and a single turn of 14AWG copper wire inserted inside the hoop.

This PDF guide provides step-by-step instructions on how to build a Bunnings Balun for your ham radio antenna. A balun is essential for matching the impedance between your antenna and radio, improving signal transmission. The guide is perfect for hams looking to enhance their radio setup on a budget. Follow the detailed instructions to create your own balun using easily accessible materials from Bunnings or any hardware store.

This antenna just requires about 24m of free space instead of 41m that a normal half wave 80m antenna needs to hang up. The so called loaded dipole uses a coil in every dipole arm to electrically lengthen the mechanical too short dipole arms. Every coil has an inductivity of 120 microHenry.

Author found a ratio between the lengths of the sides of the Delta Loop that give reasonably low SWR into a 50 ohm coaxial cable almost independent of the high above ground and other surroundings. This ratio also gives good results no matter orientation. Includes an online delta loop antenna calculator.

Vertical end fed antenna used for portable operations. The antenna will work on 80 with acceptable results, it will work fine on 40m, and it will be a good deal better than a normal 1/4 wave GP on 20, 17, 15 meters.

This article describes a multi-band antenna design for amateur radio enthusiasts by G3FEW. The antenna is designed to cover at least five HF bands with low SWR and without the need for an ATU. It is also designed to be easy to construct and adaptable for different locations. The antenna is a full-wave dipole with traps at the quarter-wave points. The traps are used to tune the antenna to different bands. The antenna can be fed with a 4:1 balun. The article includes instructions for building the antenna, as well as information on the theory behind its operation. The author also discusses the results of his tests with the antenna. This multi-band antenna is a well-designed and versatile antenna that can be used by amateur radio enthusiasts on a variety of bands. It is relatively easy to construct and can be adapted for different locations.

Dipole antennas, vertical half-wave dipole antennas with impedence tranformes that can be used for portable operations. Some well worn antenna configurations are the easiest and loudest lash-ups you can try.

Discovering a solution for limited space, the inverted L HF antenna emerges as a stellar performer. Half the size of a dipole, it ensures optimal installation in restricted areas, maintaining superb transmission (TX) and reception (RX) characteristics. Spectrum Communications' multi-band version, featuring traps, proves even more space-friendly without compromising performance. A fiberglass pole offers sturdy support, while proper grounding, an RF choke, and occasional tuning contribute to a high-performing and reliable antenna system.

This PDF document reviews the POTA PERformer Antenna by KJ6ER, providing insights and details about its performance and features. The content is aimed at hams looking for information on this specific antenna model to help them make an informed purchasing decision. It contains technical specifications, user experiences, and possibly recommendations for optimal use. The review is valuable for hams interested in portable operation and seeking a reliable antenna solution for Parks on the Air (POTA) activations.

This small dual band UHF VHF directional antenna is good choice for portable operations. This antenna is composed by a moxon antenna for the two meters band and it includes two parastatic elements for 70 cm band.

This tutorial provides detailed instructions for constructing a DIY magnetic loop antenna, ideal for amateur radio operators seeking efficient short wave communication. The design features a remote tuning system utilizing an Arduino and RC servo, making it suitable for indoor use where larger antennas cannot be installed. Magnetic loop antennas are compact and can operate effectively in confined spaces, but they do require careful handling due to the high voltages and currents they generate during operation. Users should possess the necessary technical skills to implement this project safely. The tutorial includes a comprehensive overview of the antenna's theory, specifications, and mechanical design. It outlines the components needed, including a Soviet-made variable capacitor and a digital RC servo for tuning. Safety precautions are emphasized, as the antenna can produce several kilovolts of voltage and high currents. The project is not certified for safety, and users are advised to proceed at their own risk. The tutorial also provides diagrams and explanations of the antenna's operation, making it a valuable resource for both beginners and experienced operators looking to enhance their setup.

A small active voltage probe antenna to aid reception on the LF bands

This article describes a simple yet effective multi-band vertical HF antenna design that performs exceptionally well across 80m to 10m bands. The antenna consists of a 13.4m wire mounted on a 12.4m Spiderpole, complemented by four 12m radials and a ground rod. Initially tuned with a manual LC circuit, it was later upgraded with a CG3000 remote auto ATU for convenient band switching. Despite antenna modeling software suggesting limited performance on higher frequencies, the system demonstrated excellent DX capabilities across all bands, outperforming more complex vertical antenna designs.

A hexagonal beam is a form of the Yagi antenna which is based on parasitic principles developed early in the last century in Japan for achieving gain in one direction.How HexBeam antennas works. A hexagonal beam operates exactly like Yagi antenna, but instead of a driven element that is straight like a dipole, it is a wire bent into the shape of the letter M.

This page describes a couple of parts box medicine bottle antennas that you can build. The ground side of the capacitor is soldered to the ground of the BNC connector. The positive side of the capacitor takes 5 turns around the toroid and is soldered back to itself. The center pin of the BNC connector takes 5 turns around the toroid and then continues on to the wire wound inductor. From there the antenna continues with an attached piece of wire.

A mircovert antenna assembled for the 40m version of the DL7PE antenna. A one meter long aluminum tube with 24mm diameter is used for the base (element 1) and a 50cm aluminum tube with 20mm diameter for element 2 (the extention). A pvc pipe, 34cm long and with a diameter of 38mm, is used to wind the coil on (1mm enamelled copper wire).