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LnR Precision Inc. is a North Carolina based company that specializes in Par EndFedz amateur radio antennas and MantiZ QRP Transceivers. Their most popular products include End-Fed QRP portable antennas and HF FX Series QRP Transceivers.

Hints for building a W3EDP-Antenna, includes the construction of the 1:4-balun by DK7ZB

The TMB-1 is an RF amplifier unit / receiving accessory that can be used with a low-impedance broadband loop, a high-impedance terminated loop (such as a Pennant, Flag, or Kaz Delta), and whip (telescoping rod) antennas.

Largest Capacity of 200,000 MT for Towers & market leader in India with backward integrated rolling & manufacturers of Shelters, V/UHF, Patch Panel Antennas, DIAS & DWDM Equipment

Receive-only loop antennas have some nice response characteristics that make them ideal when used for reception of skywave signals.

This web article by VK3BLG details the construction of an experimental 70cm (432 MHz) circularly polarized patch antenna, intended for satellite communication. The resource provides dimensions, feed point specifications, and impedance matching considerations for a single patch element, with discussion extending to array configurations for circular polarization. Construction involves a copper patch element on a dielectric substrate, fed via a coaxial cable. The design is based on information derived from AO-40 satellite antenna specifications, focusing on achieving circular polarization for satellite reception. The article includes specific dimensions for the patch and feed points, along with impedance values. Validation is implied through on-air satellite reception reports, with initial signal reports of **1 S-point above noise** for AO-40 beacons using a grid reflector, improving to **3-4 S-points above noise** with a 2-turn helical feed. The author references a _NanoVNA_ for impedance measurements and discusses the relationship between slot and dipole antennas in the context of patch design. DXZone Focus: Web Article | 70cm Patch Antenna | On-Air Satellite Reception | Circular Polarization

Understanding Amateur Radio NVIS Antennas and Propagation, derived from The ARRL Antenna Book and QST Articles

ICNIRP is a calculator software that allows you to determ safety distances for many know amateur radio antennas with respect to ICNIRP limits developed by DL9KCE

This QST article describes the electrical and mechanical design process for two LPs that cover the HF bands from 10-30 MHz

Dealer for Alpha Delta hf antennas, switeches, Outbacker and super antennas, morse code keys, coax cable and military products, managed by W8GEG from Medina Ohio

Limiting static surges on dipoles, verticals or end fed antennas

Ground Plane antennas and common mode

Delta loop antennas for 40 meters plans and comparison of some models

A system designed to automatically tune small transmitting magnetic loop antennas, particularly beneficial for **contest operations** where rapid frequency changes are common. The core of the system involves a PC-based control application, AutoCap, written in C#, which monitors antenna SWR via an external meter and commands a motor interface to adjust the loop's variable capacitor. The software is compatible with Windows and Linux via the Mono framework, offering a graphical user interface for monitoring system status, SWR, power, and motor commands. Key components include one or more magnetic loop antennas equipped with DC or stepper motors for capacitor adjustment, an SWR meter with data output (such as the Telepost LP-100A or a homebrew serial/USB SWR meter), the AutoCap PC software, and a motor interface. The most effective motor interface utilizes an **Arduino-based controller** with custom firmware, providing precise control over both simple DC motors and stepper motors, and supporting features like motor braking for finer adjustments. The system allows for configurable SWR thresholds, pulse widths, and motor effort settings to optimize tuning speed and resolution. Optional radio integration provides frequency hints, enabling the algorithm to learn the relationship between motor actions and resonant frequency, thereby speeding up initial tuning responses. The software also supports antenna profiles, allowing operators to save and recall specific configurations for different loops, including accumulated frequency hint data.

About the basics of what is a discone antenna for wide band or bandwidth omnidirectional applications

Benelec Pty Ltd specializes in the design and manufacturing of **antennas** and RF components, covering a broad frequency range from 0.002 GHz to 8 GHz. Their product line includes Land Mobile Radio Antennas, such as HF 2-30MHz, VHF 40-180MHz, and UHF 200-520MHz models, alongside specialized Military Antennas for dismounted, UxS, C2, and EW applications. The company also produces Cellular Antennas, including 4G/5G and GPS/GNSS types, and Marine Antennas for both vessel-mounted and fixed-site installations. Additionally, Benelec offers a comprehensive range of coaxial cables, connectors like N-Type and SMA, and various radio accessories. The company's offerings extend to RF components such as duplexers, diplexers, and 50 Ohm loads, as well as DAS components like directional couplers and hybrid combiners. Benelec provides EMP and lightning protection solutions, including 1/4 Wave Stub protectors and replaceable GAS capsules. Their product catalog also features P25, DMR, and FM Analog radios, along with portable and mobile radio accessories like batteries, chargers, and cabled headsets. The company supports various sectors with robust communication solutions.

A collection of technical articles on antennas, radios and other stuff.

Designing and constructing portable wire antennas for HF operations, this resource explores several configurations including the _foldback dipole_ for space-constrained setups and an inductively shortened dual-band dipole for 20m and 40m. It details the calculation of inductance for shortened elements, providing a Visual Basic 6.0 program screenshot that illustrates determining coil parameters like turns and length for a **25.5 uH** inductor. The document emphasizes practical considerations such as adjusting wire lengths for optimal SWR, noting that a dual-band dipole achieved SWR below 2:1 on both 20m and 40m, with careful adjustment bringing it under 1.5:1. Further, the resource describes a half-wave antenna matched with a coaxial stub, a method often referred to as the _Fuchskreis_ in German amateur radio circles, to transform the high feedpoint impedance to 50 Ohms. This monoband solution, for a 20m application, uses a stub length of **2.98m** (0.216 lambda multiplied by coax velocity factor) and a shorted stub of approximately 48cm. The coaxial stub design is highlighted for its resilience to ground proximity, allowing it to be rolled up or laid on the ground with minimal SWR impact, making it highly suitable for portable QRP operations.

KA7OEI article on homebrewing Yagi UDA antennas with practical suggestions and designing notes.

Antenna tuners are crucial for matching the impedance of antennas to the 50 ohm output impedance of transmitters. The _LDG Z-11 Pro_ is an automatic antenna tuner designed to handle up to 125 watts, making it suitable for a wide range of amateur radio applications. Its compact form factor allows it to pair well with transceivers like the _FT-857D_, providing a portable solution for operators who frequently change locations or setups. The tuner covers the 80 through 6 meter bands, offering a broad impedance match capability. Although it struggles with some loads, it performs well with typical ham antennas, even managing to load an 80 meter dipole on 6 meters. One of the standout features of the _Z-11 Pro_ is its 8000 memory slots, which enable it to remember successful matches and quickly retune when revisiting frequencies. This memory function significantly reduces tuning time, often to less than half a second. The unit is well-constructed, with improved pushbuttons and a sturdy metal case that offers good shielding. However, users should be aware of potential RFI issues and the lack of a power switch, which requires disconnecting the power cord to turn off the unit completely. Overall, the _LDG Z-11 Pro_ is a user-friendly and cost-effective tuner, offering advanced features that enhance its utility in various amateur radio setups.

Magnetic Loop Antennas for The Radio Operator with Limited Space, a two part series of articles on how to construct a magnetic loop antenna, including directions on selecting high voltage tuning capacitor

VHF, UHF and Satellite Antennas for Government, Commercial and Amateur Radio Made in Nebraska USA

With all the wire you have out, you may run into a problem with static buildup on the antennas. This static may try to make its way into your receiver, causing you major problems and damage that can run into a lot of money.

Building EH Antennas at Gemran radio club station house, by Matthias DH4FAW

Modeling small 160 meter antennas, with a focus on the vertical H antenna

Antennas, Standard Delay Line Systems, Crossfire Phasing or Hybrids

A general article on CMC, common mode choke include a description and tipical usage.

Small antenna, what causes loss and how to increase radiation resistance in small antennas., A description of loss and radiation resistance.

The 160 meter ground plane is constructed from #10 stranded insulated wire available in most hardware stores. The feedpoints / tiepoints use PVC pipe T-sections Article by W1TR

The AB2RA bowtie 80 meter antenna includes also a 40 meter dipole

Operating magnetic loop antennas requires careful consideration of RF safety, particularly regarding near-field magnetic field intensity. This resource presents calculations for magnetic field strength (H-field) at various distances from a magnetic loop, emphasizing that the H-field is significantly higher than the E-field in the near-field region due to the inductive nature of the radiating element. It provides specific formulas and examples for determining safe operating distances based on power levels and loop dimensions, crucial for compliance with RF exposure limits. The analysis compares calculated H-field values against FCC and ICNIRP maximum permissible exposure (MPE) limits for controlled and uncontrolled environments. It demonstrates that even at QRP power levels (e.g., 5W), the H-field can exceed MPE limits within a few feet of the antenna, necessitating greater separation distances than often assumed for electric field considerations. The practical application of these calculations helps amateur radio operators configure their stations to ensure personnel safety and regulatory compliance when deploying compact, high-Q magnetic loop antennas.

Hi-Z Antennas offers specialized high-impedance receiving systems, primarily focusing on phased vertical arrays for HF reception. Their product line includes preamplifiers designed for shortened vertical antennas, featuring optimized 15dB gain and array-matched characteristics. These components are engineered to enhance weak signal reception and improve signal-to-noise ratio across the HF spectrum. The company provides controllers for managing multiple vertical elements in a phased array configuration, enabling directional reception patterns. These systems are particularly effective for mitigating local noise and interference, a common challenge in urban and suburban operating environments. Specific offerings include solutions for 160-meter and 80-meter bands, addressing the unique requirements of low-band DXing. Technical details often reference components like the 2N3866 transistor in preamp designs and discuss concepts such as out-of-band attenuation. The focus remains on optimizing receiving antenna performance through impedance matching and active amplification, rather than transmit capabilities.

Digital radio mondiale DRM products, measuring tools, Magnetic field probes, RF power meters, Broadband loop antennas, DRM devices and services

Since they were first described by the French mathematician Benoit Mandelbrot in the mid-1970s, repeating geometric figures known as fractals have fascinated computer scientists, mathematicians and graphic artists.

Description and simulation of two types of rhombic antennas, using the software 4Nec2: the simple bi-directional and the terminated directional rhombic antenna

The HyGain LJ-153BA a monoband 3 element Yagi, designed for the 15 m band 21.00 - 21.45 MHz

Experiences with Loop antennas at G3YMC include some loop antenna tests and theory by G3LHZ

Radios, Antennas & More dealer from Texas USA

**LDG Z100** automatic tuner repair focuses on toroid replacement and troubleshooting. The guide provides detailed steps for diagnosing and fixing common issues with the toroid, which is crucial for the tuner's performance. It includes specific instructions on disassembling the unit, identifying faulty components, and sourcing replacements. The document is technical, requiring familiarity with electronic components and soldering techniques. It emphasizes the importance of using the correct toroid specifications to ensure optimal functionality. Successful repair of the **LDG Z100** ATU restores its ability to match a wide range of antennas, enhancing transmission efficiency. The guide compares the performance before and after the repair, highlighting improvements in SWR readings and overall reliability. Practical application of this repair extends the life of the tuner, making it a cost-effective solution for amateur radio operators. The document serves as a reference for similar repairs on other models, providing insights into common issues and solutions. It is a valuable resource for those looking to maintain their equipment without resorting to professional services.

Specialize in engineering, design and repair of all rf equipment. Dealer for two way radios, scanners, shortwave radios, wi-fi antennas, wifi amplifiers. Based in Fortuna, California.

Stop common-mode current when transmitting with an end-fed antenna. Unbalanced antennas are very prone to currents on the outside of the coax.

50 MHz extended 6-7 element ZX-Yagi antenna. Dimensions for the 7 elements and information on performance of a 2 stacked antennas featuring a total max gain of 20.8 dBi

Slot cubes are folded skeleton slot antennas with widened, folded dipoles bent into a cube to reduce size. QST Article 12 2019

Modeling compact 160 meter antennas, inverted L, half wave dipoles and linearly loaded dipole

In this article the author provides some guidelines on how to solve a common problem when stacking different types of yagi antennas on the same mast, limiting the effects on gain and radiation pattern of both antennas

22 Different Wire Antennas for the 160 Meter Band, Random Length Radiator Wire, delta loop, loop antennas, off-centered antennas, sloper, dipoles, Z antenna, Zepp and Clothesline Antennas

A Batwing Antenna Design Challenge

An unconventional antenna family, the VHF/UHF Zigzag Dipole Antennas. Design, theory and practical construction, transformation and balancing with a half wave balun.

On this page are designs for Dual Band 2M / 70cm antennas. All antennas are 50 ohm designed driver. These Yagis have a unique element called a Open Sleeve. 4 Element 5 element and 9 element Dual Band - 2M / 70cm antenna projects

MyAntennas.com offers standard and custom made multiband antennas, Baluns, Common Mode chokes and accessories. All products are designed and made by Danny Horvat, E73M an antenna design engineer formerly employed by Cushcraft Corporation.