Search results

The I0JXX is an italian company that offers market their projects, also sells electronic products of high quality, both for Ham, both Broadcast and their accessories. VHF Antennas, mosfet power amplifiers, filters, insulators, power dividers, telescopic poles, antenna masts

Overview, summary, tutorial about the log periodic antenna or aerial used for wideband RF antenna applications

Great pages about KB1SG rhombic antennas collected by EI8IC.

Solution to your OEM needs and can meet your design or vended antenna requirements for antennas from 400MHz to 10 GHz.

A quarter wave vertical end-fed antenna for the 40 meters band. As all vertical antennas, also this aerial requires a good earthing system. In this project the ground is composed by twelve 4, wires buried in the lawn by using a spade to create a slit to drop the wire into.

An analysis of the cebik dipole and other small limited space dipoles fed with open wire ladder line.

Presents a comprehensive guide for constructing a broadband Hex Beam antenna, a popular directional array for HF operation. This design offers a compact footprint and excellent gain characteristics, making it suitable for limited space installations while providing significant performance advantages over omnidirectional antennas. The resource details the specific dimensions for a five-band Hex Beam covering 20, 17, 15, 12, 10, and 6 meters, emphasizing the critical element spacing and wire lengths required for proper resonance and pattern. It outlines the construction of the center post, spreaders, and wire elements, along with the feed point assembly, ensuring proper impedance matching. The project aims for a forward gain of approximately **5.5 dBi** on most bands, with a front-to-back ratio often exceeding _20 dB_. Building this antenna requires careful measurement and assembly, but the resulting performance provides a substantial upgrade for DXing and contesting.

optimum short-wave antennas, developed by hams for hams

Located in France, DXBeam designs and manufactures a range of monoband, dual band and triband antennas, rotary dipoles, Moxons and Yagis

20m 2-element light-weight Yagi antenna

Illustrates the construction of a compact _Moxon_ beam antenna specifically tailored for the 40-meter band (7 MHz). The resource details a homebrew project by W7XA, emphasizing its design for limited space while maintaining good bandwidth and directivity characteristics. It highlights the practical application of the _Moxon_ rectangle model to achieve performance on a lower HF band. The primary content is a downloadable PDF document titled "40-Meter-Mini-MOXON-Beam-Antenna.pdf," which provides comprehensive illustrations and technical specifications for replicating the antenna. This includes dimensions, materials, and assembly instructions, making it a practical guide for radio amateurs interested in directional antennas for HF. The project demonstrates how a relatively small footprint can yield a directional antenna suitable for DXing or contesting on 40 meters, a band typically requiring much larger arrays for similar gain and front-to-back ratios. The documentation supports hands-on construction.

This project outlines the construction of a 3-element reversible quad antenna specifically designed for the 40-meter band. The materials required include pushup towers, pressure-treated posts, insulated wire, and various electrical components such as relays and a balun. The construction process is straightforward, beginning with the installation of the posts in a straight line, followed by the assembly of the antenna elements and their elevation to the desired height. The antenna's design allows for directional signal reception, making it ideal for operators looking to enhance their communication capabilities on the 40-meter band. The project includes detailed instructions on tuning the antenna for optimal performance, ensuring that operators can achieve the lowest SWR possible. Additionally, the design can be adapted for other bands by extrapolating dimensions, providing versatility for amateur radio enthusiasts. Overall, this reversible quad antenna project is suitable for both beginners and experienced operators, offering a practical solution for improving signal strength and directionality in 40-meter communications.

An interesting page about Quad antennas. Modelling QUAD antennas, comparing quad antennas to yagi antennas. Information on QUAD Antenna tuning and home brewing with help on calculating dimensions and tuning.

Why 6 meter hams design the best antennas

D3+ High Performance Antennas for Field Day. This article describes versatile broadband wire antennas. These antennas will double your effective radiated power over a dipole, will be easy and inexpensive to build and install, and will be simple to match.

Antenna manufacturer from Poland, produce dipole wire antennas, W3DZZ FD4 Windom and long wires, baluns, dealer for toroids and connectors managed by Leszek Mlynarczyk SP1BKS

Wholesale distributor of CB radios, parts, antennas, microphones, power supplies, crystals, echo boards, expanders, meters and CB accessories.

DAVIS RF Co. has been in the business of supplying the staples of wire antennas for over 30 years. DAVIS RF Co. supply all coax cables, all connectors, ladder line, rotar control cable, insulators, and we have the largest selection of wire for wire antennas. DAVIS RF Co. is the designer and trade mark holder, and primary source for Bury-Flex Tm low loss coax cable. PolyStealth Tm high strength PE insulated antenna wire, and Flex-Weave Tm wire

Fractal Antennas are a new generation of multiband antennas for wireless communications. Based on a new design concept, fractal technology.

Long Waves, Short Antennas, designing antennas for MF and LF communications

True Ladder line and Wire antennas

Coax is a very important part of a satellite station. It is almost as important as the antennas you choose. This article discusses choosing coaxial cables for satellite communication, emphasizing factors like line loss. It compares types such as RG-8, RG-58, Belden 9913/9913F, LMR-400, and hardline, highlighting their impact on signal preservation.

K9AY receiving antennas for PA6Z made by PA9M

Unique and Hard-to-Find accessories for Amateur Radio. Featuring Plasti Dip products, DK9SQ Masts, Wire Antennas, AEA Antenna Analyzers and RF Connectors too!

Over **10 million** antennas and flags have been sold worldwide by Firestik Antenna Company, a veteran-owned manufacturer specializing in both CB and amateur radio communication products. Their offerings include a range of antennas, mounting accessories, and coaxial cables, designed for various mobile and fixed applications. The company provides technical support and maintains a network of dealers for product availability. Firestik products are known for their fiberglass construction, which is evident in their _Firestik_ and _Firefly_ antenna lines. The company also produces unique items like the "342 mile per hour Firestik flag," highlighting their diverse manufacturing capabilities beyond just radio antennas. They emphasize their commitment to quality and customer service, including direct technical assistance. The company is located in Tempe, Arizona, and operates under the registered trademark of _Pal International Corporation_. They actively protect their brand, including variations like Firestick and Firestix, ensuring proper representation of their products in the market.

An Active antenna designed for VLF and shortwave radio reception. A small antenna capable of excellent performances on low bands, made on a copper plate and introductio to active antennas.

Helical antennas invented by John Kraus give a circular polarized wave. They are one of the easiest to design. Find a tube with a circumference equal to one wavelength, and wrap wire in a helix spaced a quarter wavelengt

Ham Radio On line shop, kenwood yaesu icom alincon ten tec dealer, antenna rotors, antennas, antenna mounts, microphones, antenna mas, receivers and scanners based in Essex England Uk

This is a 200 Watt PEP step up transformer for end fed full and half wave antennas without radials, designed as a 200 Watt PEP

Designing **Moxon Rectangle** antennas often involves an urge among builders to find simple "magic formulas" for element lengths. L. B. Cebik, W4RNL, argues against this simplistic approach, emphasizing that antenna dimensions do not scale linearly and are influenced by factors like wire size and height above ground. This resource presents a procedure for developing sensible design equations, starting with uniform-diameter elements and perfectly conductive materials, with adjustments for real-world materials like copper and aluminum. The core of the method involves judicious **NEC modeling** (versions 2, 3, or 4) to create a baseline dataset for regression analysis, ensuring models meet specific performance standards for gain, front-to-back ratio, and feedpoint impedance. The derived equations, presented as a BASIC program, allow for calculating Moxon dimensions (A through E) based on wire diameter in wavelengths and design frequency. W4RNL demonstrates the efficacy of these equations by designing and testing Moxon Rectangles for 7.15 MHz (AWG #12 wire), 28.5 MHz (1" tubing), and 146 MHz (0.125" rod). Modeled performance data, including gain, front-to-back ratio, and feedpoint impedance, are provided for both perfect and real-world materials, showing high efficiency and close adherence to design goals. The article also references a standalone Windows program by AC6LA that automates these calculations and generates EZNEC or NEC models.

A vertical dipole for 10, 15, 20 and 40 meters made adapting two Hustler Model 6-BTV antennas by w6sdo

Dutch Antenna and Tower Manufacturers from Slimline Square Triangular Round Towers. Antennas production include Yagi Monoband/Dipole/HF Quad /50MHz and 70MHz Yagi-Quad, VHF-UHF yagi-Quad and Comby antennas VHF/UHF/SHF

W1YW QRZ page dedicated to fractal antennas

G3TXQ pages focuses on understanding the HexBeam antennas. Basics, dimensions, multi band issues, antenna modeling.

This resource details the conversion of an 80m elevated vertical antenna to include 160m operation, focusing on a relay-switched design over a trap-based approach. It presents specific feedpoint impedance values, such as **32 ohms** for 80m and **14 ohms** for 160m, and discusses the challenges of SWR drift encountered with the prior trap system during RTTY contesting. The article thoroughly explains the design choices for elevated radials, referencing _N6LF QEX data_ to debunk common myths regarding radial length and height, demonstrating that non-resonant radials can offer superior current uniformity. The construction section provides practical insights into building the vertical, including guying strategies, material selection from scrap pipe, and weatherproofing the relay assembly. It highlights the use of a common mode choke for the relay switching line, measuring approximately 5K ohms on both 160m and 80m, and details the L/C matching network's role in achieving a 50-ohm match at the end of a 300-foot RG-11 run. The author describes a precise VNA-based radial trimming procedure, achieving resonant values within a 3 KHz range. The content emphasizes the practical application of theoretical antenna principles, particularly concerning the interaction between the vertical element, cap hats, and the matching network. It offers a candid assessment of component selection, such as using junkbox parts and acknowledging the need for future upgrades to static drain resistors. The article serves as a comprehensive case study for advanced antenna builders tackling multi-band vertical designs.

Demonstrates the design and construction of a 9-element Yagi antenna for the **70 cm band** (432 MHz), based on the DK7ZB concept. The resource details EZNEC+ calculations for a single antenna, providing gain, sidelobe suppression, and front-to-back ratio figures. It also presents a comprehensive analysis of stacking two such antennas, including optimal stacking distance (1000 mm) and the resulting performance enhancements for the stacked array, such as an increased gain of 17.03 dBi. The article includes detailed drawings, wire file dimensions in millimeters, and azimuth/elevation plots for both single and stacked configurations. Practical construction steps are documented with original photographs, illustrating element mounting, the **28 Ohm matching system** using two quarter-wave 75 Ohm transmission lines, and the critical N-connector wiring. It also covers the iterative process of fine-tuning the driven element length to achieve a return loss of 20 dB, validating the EZNEC+ simulation results with actual measurements.

AOR USA Web site, manufacturer of base and mobile receivers, handheld receivers, digital voice modems, spectrum display units, frequency monitors and antennas

A Bulgarian bazooka antenna project by LZ2ZK

A simple quarter-wave length vertical for 40m band using a 12 m spiderpole

The PDF document, titled "J-Poles," presents various J-pole antenna designs covering the 50 MHz to 450 MHz frequency range. It includes construction details for several specific bands, such as a 6-meter J-pole, a 2-meter J-pole, and a 70-centimeter J-pole. The content outlines the fundamental principles of J-pole operation, including the quarter-wave radiator and half-wave matching stub. Each design features specific dimensions for elements like the radiator length, stub length, and spacing, often expressed in inches. The document also discusses feeding arrangements and impedance matching considerations inherent to J-pole antennas. It provides practical guidance for homebrewing these antennas using common materials like copper pipe or wire elements. The resource offers insights into the advantages of J-poles, such as their omnidirectional pattern and ease of construction, making it a practical reference for radio amateurs interested in VHF/UHF antenna projects.

Progress in Design of Extremely Short Transmitting Antennas Short and still efficient, how is that possible? By Juergen Schaefer, DL7PE author of the MicroVert antenna concept. The MicroVert introduced in this document is an extremely short and hardly visible short-wave antenna with outstanding radiation properties

Comparison of several UHF antennas by DF9CY

For radio amateurs seeking compact and efficient antenna solutions, particularly for restricted spaces or noise reduction, HF loop antennas present a viable option. This resource compiles several articles from the ARRL, detailing the theory, design considerations, and practical construction of various loop configurations. Topics include small transmitting loops, receiving loops, and multi-band designs, often emphasizing their performance characteristics such as directivity, bandwidth, and impedance matching. The collected articles provide insights into the comparative performance of different loop geometries, such as circular versus square loops, and discuss the impact of conductor size and tuning methods on efficiency. Practical applications are explored, including their use in portable operations, stealth installations, and urban environments where noise mitigation is critical. The content often includes construction diagrams, parts lists, and performance data derived from modeling or field tests, enabling hams to replicate or adapt the designs for their specific operating conditions.

Glomex manufactures quality marine antennas distributed world wide.

One specific challenge in the KazShack, operating Single Operator Two Radios (SO2R), involved sharing a K9AY receive antenna between two transceivers without direct RF connection or manual feedline swapping. The solution, detailed in this project, adapts the **W3LPL RX bandpass filter** design to split 160m and 80m signals, feeding them to separate radio inputs while maintaining isolation. This approach also addresses the issue of strong broadcast band interference from a nearby 50KW WPTF transmitter on 680kc. The construction utilizes T-50-3 toroids and NP0 ceramic capacitors, built in a "dead bug" style on copper clad board. Each band's filter coils are identical and resonated to the desired frequency using an MFJ-259 antenna analyzer. A single DPDT relay, controlled by a remote toggle switch mounted on an aluminum panel, facilitates quick band switching between radios, simplifying low-band operations. While some signal loss is noted, the expected lower noise levels from the receive antenna are anticipated to compensate, potentially reducing the need for constant volume adjustments during toggling between transmit and receive antennas.

In these slides, differences between spiderbeam antenna and hexbeam antennas are explained comparing performances and measurements.

Online helix antenna designer, calculate size of helix antennas online

This low power transmitter is developed for ARDF exercising purposes but of course can be used as super QRP transmitter either. With 1 or 2 meter wire as antenna and a ARDF receiver with ferrite-rod antenna the range is about 100m but with better antennas and a 'real' receiver the range is probably much larger.

This page will help you answer important questions about antenna selection before you talk to a supplier. After reading this paper, you should be able to better determine the most important parameters you need to know for your antenna selection criteria.

We offer uniden radio scanners and radio scanners mobile ,base station antennas ,low prices,free shipping in the U.S.A