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Designers and manufacturers of radio Frequency antennas. HF - 3000 MHz TET Emtron HF Yagis, Antennas for Wireless applications, Marine antennas, Land mobile, Mobile antennas.

Basic information on the folded dipole antenna

Choosing a vertical antenna. Buying guide to amateur radio HF vertical antennas by Bencher inc

How could we share the Beverage antennas on more than one station using this homemade remote antenna switch, a project by TK5EP

A balun is a MUST for dipoles or similar antennas when they are feed with coaxial cables. Many hams connect the center conductor of the coaxial cable to one side of the dipole, and the shield to the other. Wrong!

cocoaNEC 2.0 is an opensource Mac OS X application intended primarily for the design and modeling of antennas by Kok Chen, W7AY

This article describes a project of asymmetrical hatted vertical dipole, a portable antenna that can be used for field day operations, sota, campings or even for fixed installations. This is a freestanding 20-10m antenna that is really easy to build, easy to tune and relatively easy to carry.

Notes on Axial-Mode Helical Antennas in Amateur Service. Helix Basics, Modeling Issues, and Short Helical Antennas Over Perfect Ground

TX RX Systems Inc. manufactures signal boosters, rf antennas, transmitter combiners, cell enhancers, land mobile radios, duplexers, receiver multicouplers, bidirectional amplifiers, bda, rf amplifiers, rf filters, rf cavity filters, rf combiners, rf components, in building rf coverage, repeaters, repeater amplifiers, rf management equipment, rf systems, and rf solutions. TX RX Delivers Reliable Solutions.

An engineering oriented organization specializing in the design and manufacture of high performance parabolic antennas, 3dB high power RF couplers, Antenna power splitters, directional RF couplers and more items for RF transmission from HF through Microwave frequencies.

Collection of different techniques to homebrew PVC yagi antennas, including elements assembling, baluns and chokes, radiator box tips and tricks by dk7zb

Some antenna manufacturers place baluns at the incorrect location in LPDA arrays. If we consider what the balun does we can see how the mistake occurs.

The document provides a comprehensive overview of baluns, which are devices used to connect balanced loads, like dipole antennas, to unbalanced inputs, such as coaxial cables. It covers various types of baluns, including voltage and current baluns, and their design, construction, and testing. The text discusses the importance of baluns in preventing RF currents on coax shields and their applications in Ham radio setups. It also includes practical advice on selecting and using baluns based on antenna impedance and power ratings, along with detailed performance evaluations and construction tips for different balun configurations.

A shortened 160 meters band antenna for hams who do not have 260 ft of space, based on a open-wire-fed short dipoole

Theory of horizontal loop antennas, as discovered by G2PL using a lowered quad antenna and theorized by ZS6AKA

Understanding Gain differences, j-pole and end-feed vertical antennas.

The G5RV multiband HF antenna, designed by Louis Varney (G5RV) in 1946, is a popular compromise antenna offering good overall performance on most HF bands when paired with an external antenna tuner. The basic full-size G5RV measures 102 feet across the top for 80 through 10 meter operation and is fed at the center via a 34-foot low-loss feed-stub. This interaction between the radiating section and the feed-stub facilitates matching across 80-10 meters with a standard tuner, often eliminating the need for ladder line directly to the shack. The antenna's design center frequency is 14.150 MHz, configured as a 3/2-wave dipole on 20 meters, with its 102-foot length derived from long-wire antenna formulas. Construction details emphasize the matching section, which can be open wire, ladder line (window-type), or TV twin lead. Each type has a specific velocity factor (VF) affecting its physical length for an electrical half-wave on 14 MHz; for instance, open wire requires 33.7 feet (VF 0.97), ladder line 31.3 feet (VF 0.90), and TV twin lead 28.5 feet (VF 0.82). The article provides formulas for calculating these lengths and discusses the antenna's behavior on individual bands, from 3.5 MHz where it acts as a shortened dipole, to 28 MHz where it functions as two three-half-wave long-wire antennas fed in-phase. Practical construction notes include recommendations for vertical descent of the matching section, sealing the coax junction, providing strain relief, and winding a coaxial choke coil to mitigate common mode current. The resource also presents dimensions for double-size (204 ft) and half-size (51 ft) G5RV versions, along with their corresponding matching section lengths for various line types, making it a versatile reference for hams considering this classic wire antenna.

Offer a wide range of homebrewing projects mainly for VHF UHF operations. From vhf antennas to preamplifiers, chargers and power supplies

A 50-ohm 10W resistor forms the core of this portable QRP antenna, designed by _K0EMT_ for convenient operation on 160m and 80m. The construction involves soldering the resistor to a BNC connector, with one lead to ground and the other to the center conductor, then insulating the assembly. This minimalist design aims to provide a highly portable solution for low-band QRP operations, acknowledging the inherent trade-offs between antenna size and efficiency. Testing with an antenna analyzer revealed low SWR on both 160m and 80m, with a Yaesu FT-817 confirming good matching. While 40m and 30m showed higher SWR, the primary focus remains on the lower bands. The author successfully tested the antenna with **2.5W CW** output, demonstrating its practical application for QRP field operations where ease of deployment is paramount, even if it means sacrificing some **gain** compared to full-sized antennas.

how to make a gamma match for a antenna. The Gamma match is the most used matching device used for yagi beams.

Luksa industries design and manufacture mechanically operated aluminum telescoping masts and telescoping tripods to support communications and military antennas

Building a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

Dedicated to State-of-the-Art lightweight portable radio. Sotabeams produces and sells amateur radio products dedicated to ham radio portable operations. Antennas, supports and masts, filters, wires and more accessories for amateur radio.

An homemade portable trapped dipole antenna for 40 and 80 meters band with an optional extension for the 20 meters.

A javascript online calculator for popular wire antennas, from the standard easy to build flat-top dipole, to the inverted V dipole, but also the Quad Loop, and the equilateral delta loop antenna

Centre fed half wave dipoles make great, simple and effective antennas for the HF bands. Sometimes however, the centre feed is not ideal. This great project will improve the overall antenna performance.

Ferrite rod antenna or aerial, a form of RF antenna that is widely used in RFID and transistor radio applications.

Basic of shortwave antennas

Canadian dealer, specializes in supply and installation of free-standing towers for commercial and amateur radio use. We also supply ham transceivers, antennas, rotors and accessories.

Comparison of 50 and 70 Mhz antennas, commercial and home made projects

A very basic guide to antennas concept. Explain the usage of dummy load, basic antennas like dipole o j-poles.

DF9CY implementation of W1HIS suggestion of inserting a common mode choke into a 40m antennas feed-line.

Using our components you can build a rotating tower with greater capability than 3-4 static towers. A rotating tower allows common rotation of HF stacked arrays, VHF and UHF arrays, and antennas mounted at optimum heights. Component design also allows tower shunt loading and end support for wire antennas

The basics of what is a discone antenna for wide band or bandwidth omnidirectional applications.

Analysis of an antenna trap where a coil is formed of a length of coax cable, the outer conductor of one coax end is tied to the inner conductor of the other coax end, and the remaining connections form the terminals for the trap.

Icom Kenwood Yaesu MyDel dealer, offer a wide range of ham radio products, transceivers, antennas, rotators, microphonrs, aerials, dummy loads, rf amplifiers and scanners based in UK

Have you problem with your RG cables ? This page describes a smart antenna box using an RG-cathode for 3 antennas. The remote control needs just a simple wire and the GND for remote-control

A scanned PDF of this interesting book on HF Dipole antennas published by Stanford Research Institute

The NCDXF/IARU International Beacon Project operates a worldwide network of 18 high-frequency radio beacons, continuously transmitting on 14.100, 18.110, 21.150, 24.930, and 28.200 MHz. These beacons, initially launched in 1979 with a single station and expanded to the current 18-beacon system in 1995, provide reliable signals for both amateur and commercial users to assess current **ionospheric propagation** conditions. The system's design, construction, and operation are managed by volunteers, covering hardware and shipping costs. The resource details the evolution of the beacon network, including the transition from Kenwood TS-50s transmitters to Icom IC-7200 radios with a new controller design implemented in 2015. It explains how listening for these 100-watt signals, transmitted to vertical antennas, allows operators to determine band openings and optimal propagation paths globally. The content also references three QST articles providing historical context and technical specifics of the beacon project. Practical information includes methods for identifying transmitting beacons via a schedule or specialized software like FAROS and Skimmer, which integrates with the **Reverse Beacon Network** for automated monitoring.

An interesting article on random wire antennas, and how to choose the optimal lenghts for multiband operations.

An off centre fed dipole, with 10 feet of vertical radiator. It needs no tuner on 40m, 20m and 10m by M0UKD

A project of a 5 Antennas Relay Switch Box, all Switches & Relays have both contacts wired in parallel to improve reliability of operation, to prevent static build up, when an antenna is not in use the feeder coax is grounded.

Deploying robust antenna infrastructure for both fixed and portable operations often requires specialized support structures capable of withstanding environmental stresses while providing optimal radiating element placement. SMC offers a range of solutions, including pneumatic masts and push-up masts, designed to facilitate rapid deployment and reliable long-term support for various antenna types. Their product line encompasses antenna mounts, poles, and complete antenna systems, addressing the critical need for stable and efficient RF communication. The company's offerings extend to HF antennas, including dipoles and _NVIS_ (Near Vertical Incidence Skywave) antennas, which are crucial for short-range regional communications on bands like 80m and 40m. These systems are engineered for durability and performance, ensuring signal integrity across diverse operating conditions. With over **65 years** of experience, SMC has established itself as a global manufacturer in this niche. Their product portfolio also includes antenna support towers, catering to more permanent installations requiring significant height and load capacity for multiple arrays.

G3TXQ study on coaxial cable demonstrate that it can reduce an element's length by something approaching the Velocity Factor of the cable

Spanish radio dealer offer accessories, antennas and battery chargers, mounting accessories, cables and connectors, radio kits, power supply, pmr, vhf/uhf radios, all products for CB, ham radio and SWL.

The rhombic antenna is often claimed to be an exceptionally good antenna with very high gain. Modelling rhombic antennas

A 4 element addition for 10m to an existing 4 element yagi (ZX antennas)

All about homebrew, antennas, accessories for shack, digital tecniques and more..

Prince Edward Island. The PEI DX Lodge offers a turnkey operation from a custom designed shack featuring state of the art transceivers/amplifiers, etc. and the ultimate in antennas on every band.

A complete guide to magnetic loop antenna construction, with analysis of multi-turn and single-turn magneti loops, and and insight on choosing the optimal capacitor, or homebrewing your own butterfly capacitor