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A Six-element Yagi Beam for 6 Meter by W1JR proiddes a power gain of 10.2 dB over a dipole it is built on a 24 foot long boom

Elk Antennas to give the Ham log periodic antennas with the best gain, directivity, and front to back ratio possible for the size and price.

Installing a mobile rig in a vehicle requires careful planning and execution to ensure optimal performance and safety. The process begins with selecting the right equipment, such as the ICOM IC706MKII for low bands and the ALINCO DR-610 for VHF/UHF operations. Proper mounting is crucial; both radios are strategically placed under the back seat of the Silverado, allowing for a clean installation while maintaining passenger comfort. The Hustler antenna, equipped with various resonators, ensures coverage across multiple bands, while the LDG automatic antenna tuner fine-tunes the match for efficient operation. A remote head for the tuner enhances accessibility, making adjustments easier while driving. Each step of the installation is documented to provide insights and tips for fellow operators looking to enhance their mobile setup. The experience shared here reflects practical knowledge gained through hands-on work, aiming to inspire others in the ham community to undertake similar projects.

An interesting guide to aerials comparing height, gain and angles

A two element beam antenna for ten meters band. This home-brew two-element beam is the perfect introduction to rolling your own gain antenna

The standard J-Pole antenna is a end fed 1/2 wavelength antenna, in this article is explained also how to build an expanded Super J Pole that provides about 4.5 dbd gain. These antennas can be built from EMT electric conduit pipe

The Homebase-10 is a wire halo antenna for 10m built with DIY store parts, effective despite its small size. Includes a dual-band version for 10m and 6m with gain around 0 to -2dBd, near omnidirectional pattern, and horizontal polarization. Overview based on a 2008 Practical Wireless article.

Constructing a multi-band fan dipole for HF operation presents unique challenges, as VE2XIP demonstrates through his 2012 project to replace an existing commercial antenna. He details the process of calculating wire lengths using the 468/frequency formula, emphasizing the critical importance of equal leg lengths for each dipole element. The author shares practical insights gained from building at ground level, noting how elevation impacts resonant frequency and SWR, particularly for lower and higher bands. VE2XIP's experience highlights the iterative nature of antenna tuning, starting with the lowest frequency band (80m) and working upwards. He provides a specific example of trimming calculations and offers a clever tip for accurate wire removal. The article also touches on the mechanical aspects, such as dowel spacing for wire support and the benefits of a pulley system for repeated raising and lowering during the tuning process. Field results showed significant performance gains over the previous Alpha-Delta DX LB Plus, with **20 dB over 9** signal reports on 80m compared to 57. The project cost around **$100** for hardware, proving a cost-effective alternative. The author also discovered a bonus 6m capability and achieved an inverted-V _obtuse angle_ of approximately 115 degrees, contributing to a surprisingly stealthy installation.

Italian ham radio dealer for major brands like Icom Kenwood Yaesu HY-GAIN Heil Sound Rigexpert Palstar GAP antennas Diamond SteppIR and others

Presents an alternative construction method for isolated element Yagi antennas, specifically for VHF/UHF operation. The technique utilizes commercially available vibration damping clamps (resin support blocks) to isolate 1/4-inch aluminum rod elements from a 1-inch square aluminum boom, simplifying the build process by eliminating the need for custom-machined insulators. This approach is demonstrated through the construction of 6-element Optimized Wide-Band (OWA) Yagis for the 2-meter, 1.25-meter, and 70-centimeter bands, which are well-suited for portable contesting arrays due to their light weight and decent gain. The document provides detailed specifications for element and boom materials, along with step-by-step procedures for cutting, drilling, and tapping. It also covers the fabrication of a feedpoint bracket for a direct 50-ohm SO-239 coax connection and discusses considerations for horizontal versus vertical polarization, including mast placement. The resulting 6-element models achieve an average free-space gain of 10.2 dBi and a 25 dB front-to-back ratio, with the construction technique being scalable for higher gain designs. Included are parts lists with sources, detailed mechanical drawings for each band, and EZNEC data for the 2-meter and 70-centimeter designs, showing both free-space and 30-foot elevation performance. The designs are optimized from W4RNL's original concepts using HAMCALC, ensuring good gain, passband characteristics, and front-to-back ratios for wideband Yagi operation.

Constructing a basic multimeter involves integrating a 0-1mA meter movement with various shunts and multipliers, selected via a switch, to create a versatile instrument capable of measuring DC volts, current, and resistance. The design outlines two main units: a primary unit handling six DC current ranges up to 1 amp and eight DC voltage ranges up to 1000 volts, alongside an internal battery for an ohms range up to 200,000 ohms. This approach allows for a practical, hands-on understanding of meter operation. An add-on unit further extends the multimeter's capabilities, incorporating a meter rectifier and switched series resistors to provide four AC voltage ranges up to 100 volts. Additional shunt and series resistors, designated Ra and Rb, are included to expand the instrument's range to 10A and 5kV, demonstrating how modular design can enhance functionality. When this add-on is in use, the main instrument is set to measure 1mA FSD, connecting via specific lugs. Component selection emphasizes precision, with 1% tolerance high stability resistors for series elements and Eureka resistance wire for shunts. The design specifies values calculated for a meter with 60 ohms internal resistance, noting that these would require modification for different meter characteristics. Experimental adjustment of shunt values is recommended to ensure accurate readings against a calibrated reference meter, reinforcing practical calibration techniques.

The prototype for this amplifier was originally designed for 70cm and was used on the 2004 3B9C Dx-pedition to Rodriguez Island for satellite and EME. It had a noise figure of 0.49dB with an associated gain of 20dB.

Showcasing innovative RF solutions, Hofi Hochfrequenztechnik manufactures high-quality _antennas_ and RF switches. Their products, including the **versatower** and **fritzel** brands, cater to both casual operators and serious DXers. With a commitment to performance, Hofi's offerings enable operators to achieve optimal signal gain and reliability in various conditions. The company's expertise in antenna design ensures that users can effectively communicate across _HF_ bands, enhancing their overall operating experience. Whether setting up a new station or upgrading existing equipment, Hofi provides essential tools for successful ham radio operations.

The Cambridge University Wireless Society (CUWS) serves as the amateur radio society for students and staff at Cambridge and Anglia Ruskin Universities, fostering interest and activity in two-way radio communication. It provides a platform for members to engage with various aspects of amateur radio, including operating, technical experimentation, and community building within the university environment. The society's activities typically encompass station operation, antenna construction, and participation in contests and DXing. As a university-affiliated club, CUWS offers practical experience in radio theory and application, often utilizing the club callsign _G6UW_. Members learn about different modes of operation, such as CW, SSB, and digital modes, and gain hands-on experience with transceivers and associated equipment. The society's focus includes preparing members for amateur radio licensing exams and promoting ethical operating practices. Participation in CUWS provides a foundation for future involvement in the broader amateur radio community.

To gain Tonga DXpedition Award it is necessary to have QSL confirmed contacts with two amateur radio expeditions from Tonga (A35), on two bands, with two diffrent modes. Available also to SWLs

A 70 cm yagi antenna design by YU7EF includes tables with antenna elements dimension and spacing. This UHF Yagi antenna plan provides a maximum gain of 17.93 db

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.

AN-SOF is a professional comprehensive software tool for the modeling and simulation of antenna systems. AS-SOF allows to describe antenna geometry, Choose construction materials, Describe the environment and ground conditions, Describe the antenna height above ground, Analize radiation pattern and front-to-back ratio, Plot directivity and gain, Analize input impedance and VSWR,Predict antenna bandwidth

Gain we can expect of a parabolic antenna by F4DAY

Antuino is an accurate instrument that can be used in the field to measure SWR, field strength, modulation, etc. In the lab, it can be used to sweep filters, measure gain, distortion, frequency response, etc. It works upto 150 Mhz. On the third harmonic, it is usable on 435 Mhz band as well (with reduced sensitivity).

The CobWebb antenna project is a compact, multiband HF solution ideal for amateur radio operators. Covering 14-28 MHz, it features a square dipole array with near-omnidirectional coverage and unity gain. This guide details a DIY approach, using a 1:4 current balun for impedance matching. Construction involves aluminum and fiberglass tubing, with optimized element tuning for SWR performance. Weather resistance improvements and resonance shift considerations are also discussed. Build your own CobWebb antenna for an efficient, space-saving HF experience.

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

Valon Technology designs and manufacturers low cost, reliable radio frequency products such as RF Synthesizer modules, RF Frequency Dividers and Phase Gain Detectors. Main markets are military/defense, test engineering, radio astronomy, research centers and universities

Antennas for the 1296 MHz based on the construction plans of some Yagis 35 elements by DL6WU, F9FT, DJ9YW. These antennas features a boom of about 3 m and gives a gain of about 17.8 dBd

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.

Offers a range of high-performance RF interconnect solutions, addressing the critical need for reliable signal integrity across diverse radio frequency applications. Their product line includes custom cable assemblies, various **RF connectors** (such as SMA), adapters, and terminators, designed to meet stringent specifications from DC up to 40 GHz. These components are essential for maintaining low insertion loss and excellent VSWR in demanding environments, from test benches to operational communication systems. The company specializes in providing tailored solutions for both commercial and government sectors, emphasizing precision manufacturing in Warner Robins, Georgia. Their offerings are crucial for engineers and operators requiring specific lengths, connector types, and performance characteristics for their radio equipment and test setups. Ensuring robust connections and protection against transient voltage events, their **surge protectors** are integrated into systems to safeguard sensitive electronics from damage, a common concern in outdoor or high-power installations.

Adapting a common PC earphone with microphone to connect to a transceiver via a homemade pre-amplifier, using a simple chip with aprox 10 db gain. Includes a schematic diagram

An Hentenna project for the six meters band. The standard size of standard hentenna is width 1/6 wavelength x height 1/2. The antenna build in this project is a full wavelenght antenna for the 50 MHz providing a 6.8 dbi gain.

YU7EF EF0206 2m Band 6 Element Yagi Antenna project, provides 11.8 dbi gain

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.

A HF power amplifier with a push-pull of AFT09MS015N. The (small-signal) gain of the amplifier is around 26 dB in the lower HF band and goes down to about 24 dB on the higher end and still around 21 dB at 50 MHz. Its input matching is relatively good at the lower HF and degrades above 10 MHz.

An FCP is not magic. It has no gain. An FCP improves an antenna system by replacing more loss with less loss. Some have been able to erect better wires in the air because the small size of the FCP allowed better placement of the antenna.

Building A Full-Wave Quad Loop Antenna for 6 Meters. This is an easy antenna to build and the materials cost about $15-20. It exhibits 1.8dB gain over a 1/2-wave dipole. Using an open-wire parallel feedline (commonly called ladder line) with an antenna tuner, it tunes up on the 10m band as a 5/8-wave loop as well

A W8JK/Moxon antenna variant with 400cm long monopoles is detailed, demonstrating a **1dbd** gain improvement over the traditional Open-Folded W8JK. This design, relying on the _Moxon principle_, achieves higher radiation impedance, leading to increased antenna efficiency and reduced losses. The article includes VNA output data for various HF bands, showing impedance characteristics from 10.1 MHz to 50.1 MHz, and provides NEC model wire definitions for the antenna structure. Field tests performed by F6IIV, Marc, compared his W8JK Moxon style antenna against a Cobweb antenna at the same height. Results indicated the W8JK Moxon variant provided a **6dB** (1 S-meter point) advantage on most bands from 20m to 10m, and a significant 10dB (1.5 S-meter points) advantage on 15m. The antenna features a 2.70m boom and a turning radius of less than 3 meters, making it suitable for limited space installations while maintaining bi-directional performance on most bands.

A document that will guide you on Coaxial-Cable trap optimization process to gain on global antenna performance and on increasing effective bandwidth.

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

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.

The Covey Hill Amateur Radio Club operates a 146.685 MHz analog repeater with an 88.5 Hz PL tone, alongside several digital repeaters. The resource details specific frequencies and modes for D-STAR (145.590 MHz, 1266.300 MHz voice, 1297.675 MHz data on 23 cm), DMR-Marc (448.525 MHz), DMR-Brandmeister (441.750 MHz), Yaesu Fusion (449.725 MHz), and P-25 Digital (147.315 MHz). It also lists Echolink node 595040 (VE2REX-R) as an access point for the club's network. A recent update, dated June 19, 2024, announces the VE2REX analog repeater and Echolink are fully functional again, after resolving issues including a conflicting 100.0 Hz tone, software repairs for Allstar and Echolink, a suspected defective USB port on the Mini PC, and a faulty exciter in the Motorola Quantar repeater. Guy, VE2VMT, was instrumental in troubleshooting these problems. The club, established in 1994, provides a calendar, news, links, and membership information, with Linda Cullen, VE2NJK, serving as president and VA2DBJ as webmaster.

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.

Constructing a directional antenna for VHF operations, particularly for 2-meter band contests or local communication, often involves balancing performance with ease of build. The Moxon rectangle, a compact two-element beam, offers a good front-to-back ratio and gain in a smaller footprint compared to a Yagi, making it suitable for portable or temporary setups where space is limited. This design typically uses a driven element and a single reflector, bent into a rectangular shape to achieve its unique radiation pattern. The article details the construction of a 2-meter Moxon antenna, specifically for 144 MHz, utilizing readily available materials like PVC pipe for the frame and copper wire for the elements. It outlines the dimensions for the driven element at 970mm and the reflector at 910mm, with a spacing of 140mm between them, and a 50mm gap at the element ends. The feedpoint is a direct 50-ohm connection, simplifying matching requirements. The project includes a parts list, a basic diagram illustrating the element layout and dimensions, and photographs of the completed antenna. The author notes the antenna's performance during a QRP contest, achieving contacts up to 100km with 5 watts, demonstrating its effectiveness for low-power VHF work.

2 Wavelength ,2 Meter Bi-Square Beam , 5dbd gain. This antennas are very cheeap to build and their radiation pattern is similar to a figure 8 with maximum signal through the loop but they may be used as a near-omnidirectional antenna

Experimental Long Boom Antennas - CP, LPDA, multiband with several NEC Files for 50MHz 144MHz 222 MHz 432MHz but also 902MHz and 1296 MHz Antenna projects. Includes also for each antenna model, in a general comparison table each antenna characteristics including Directive Gain, G/T, E-F/R, H-F/R abd Boom Length. This is a great value comparison table of several commercial and home made VHF UHF antenna projects.

Hy-Gain TH3jr Tri-band HF 3 Element Beam Covers 10, 15 and 20 Meters assembly instruction manual

The Dickson County Amateur Radio Club (DCARC) operates as a local organization for amateur radio enthusiasts in Middle Tennessee, providing a focal point for hams in the area. The club's activities typically encompass local nets, technical discussions, and support for emergency communications, aligning with the public service aspects of amateur radio. Members often engage in various operating modes and bands, sharing knowledge and experience to enhance their collective skills. Club members participate in field days, local contests, and community events, demonstrating the practical applications of amateur radio. These gatherings offer opportunities for new hams to gain practical experience and for seasoned operators to mentor others, strengthening the local amateur radio community. The DCARC serves as a hub for camaraderie and mutual support among its members, contributing to the vibrant ham radio scene in Tennessee.

Utilizing snap-on ferrite cores and practical insights, the author enhances their shack's cleanliness against electromagnetic interference. With meticulous experimentation and installation, they improve noise levels across HF bands, reflecting on the effectiveness of their filter in minimizing common-mode disturbances. Updates underscore ongoing refinement and cautionary advice for optimal filtering and radio reception amid changing RF environments.

1260 MHz yagi antenna for ATV with a total Bandwidth (3 dB) 1240-1280 MHz and 10 dBd gain

The video delves into the significance of interference reduction in ham radio setups by utilizing ferrite materials. It demonstrates the use of spectrum analyzers and tracking generators to showcase the performance of ferrite devices in minimizing noise levels. The analysis includes insights on resistance levels, attenuation factors, and the impact of using multiple ferrite clamps or rings to enhance noise reduction capabilities. Viewers gain a deeper understanding of ferrite composition, characteristic curves, and winding techniques for effective noise attenuation in different frequency ranges. Overall, the video serves as a comprehensive guide to optimizing interference reduction in radio environments through the strategic use of ferrite materials.

An analysis and performance improvement of the HyGain TH3JR on the 20 meters band.

Three cell Lipo batteries for the FT-817 work really well, although not really sure about taking them on aircraft. The Lipos intended for use on RC Electric airplanes generally have a very low internal resistance and no internal protection against short circuit.

In this article, Steve G0UIH presents a straightforward guide for constructing a lightweight 15m 3 Element Yagi antenna with impressive performance metrics. With a focus on ease of construction and efficiency, the design boasts a nearly 8.2dbi forward gain and 30db front to back ratio. Utilizing readily available materials and a hairpin match for impedance matching, this Yagi offers broad bandwidth and simple tuning for optimal operation across the 15m band.