Search results

An antenna does not have to be resonant to work, as the primary reason for resonance is to eliminate the need for an impedance-matching device. A non-resonant wire dipole fed with open-wire line and an antenna tuner can function as an effective multiband antenna. Two wires are essential for powering an antenna, ideally with a balanced configuration like a dipole fed by parallel-wire line, though coaxial cable can be used with a 1:1 balun to mitigate RF feedback on the shield. Antenna gain is achieved by shaping and aiming RF energy, concentrating it in a particular direction, as seen in beam antennas or shaped radiation patterns of wire antennas. The function of an antenna tuner is to match the transceiver's 50 Ohm output to the antenna system's impedance, which can vary widely. Wire antennas do not always require center feeding; end-fed long wires or off-center-fed dipoles (Windom antennas) can be used, often requiring a counterpoise or radial system. Dipole antennas do not need to be perfectly horizontal; their legs can be bent, inclined, or even vertical, affecting feed point impedance. Vertical antennas shorter than a half wavelength necessitate a ground system, typically comprising radial wires, with more radials generally leading to greater efficiency. A 1:1 SWR indicates an impedance match but does not guarantee a good antenna, as an inefficient antenna with a poor ground system can still show a perfect SWR while wasting RF as heat. Always using the best feed line affordable is crucial for minimizing loss and maximizing RF signal delivery to and from the antenna.

If you find external wire antennas obtrusive for amateur radio or short wave listening, then this is the antenna for you, is just 1 meter diameter

How to build a high gain vertical antenna for the UHF amateur or CB Bands, by radio experimenters handbook

The provided resource offers a downloadable ZIP archive, "6 meter moxon.zip," containing comprehensive design files for a **6-meter Moxon antenna**. Specifically, it includes antenna models in EZNEC format, allowing radio amateurs to simulate and analyze the antenna's performance characteristics. The archive also features detailed drawings, photographic documentation of the construction, and various plots illustrating the antenna's radiation patterns and impedance matching. Authored by Allen Baker, KG4JJH, the content focuses on a horizontally polarized Moxon antenna optimized for 50.5 MHz. The EZNEC files, such as "Moxon 6m 50.5 MHz H-POL.EZc," provide precise geometric and electrical parameters for replication or modification. The collection of files, totaling approximately 10 MB, serves as a practical guide for hams interested in building or understanding the design principles of a compact, directional 6-meter antenna, presenting both theoretical models and visual construction aids.

homebrew an helix antenna for 435 MHz by VE2ZAZ

A coaxial cable tuneable magnetic loop antenna for 7MHz. This experimental antenna does not require a tuning capacitor

A multiband end-fed antenna that cover 3.5 to 30 Mhz using a 1:64 Balun based on a FT240-43 core

WorldRadio Article on Petlowany antennas base on this principle: if a length of wire is wound into a spiral-shaped coil and excited by a radio frequency current connected to the innermost portion of the coil, it will then, and only then, exhibit RF characteristics that closely approximate those of a resonant linear wire of the same length

Amateur radio towers by Wade Antenna ltd. Wallmounts,masts and accessories, tripods, dmx self spporting towers, telescoping masts

The ultimate satellite Omni Antenna by Howard Sodja, W6SHP. The Lindenblad antenna consists of four half wave folded dipoles slanted 30 degrees to the horizon, oriented 90 degrees to each other in azimuth, spaced 0.3 wavelength apart

A 5-band (20m-10m) HF antenna - Just 7ft square and great for a small garden. Build it yourself for around 60 GBP.

About Stacking yagi antennas by OH1ZAA

This is a resonant, half-wave, vertical antenna. It takes up little space in the back yard, was designed for operation on a single frequency 80 meter PSK net, and is reasonably inexpensive to construct by Chuck Hines, K6QKL

5 Band 1/4 wave Telescopic Antenna. The 20m to 10m, antenna is simple and cheap to make, and has a performance that matches commercial antennas but at cost considerably lower. The design was purposely based on a telescoping fibre glass fishing rod as this allows it to be easily stowed away in the car.

The document discusses a two-element parasitic Delta-Loop array for the 40 meters band, aimed at radio amateurs interested in antenna projects. It provides detailed plans and instructions for building a homemade Delta-Loop antenna.

Online javascript antenna calculator designed to give the critical information of a particular beam antenna, in this case a seven element Yagi, for the frequency chosen.

Arrow-Style VHF/UHF portable satellite antenna by VE2ZAZ

Operating on the 12-meter and 17-meter WARC bands often benefits from directional antennas that offer gain and front-to-back ratio in a compact footprint. This resource details the construction of a dual-band wire beam, specifically a _Moxon Rectangle_ design, for these two bands. It outlines the use of fiberglass tubing for spreaders, _Flexweave_ wire for the elements, and an aluminum hub with die-cast flanges to create a robust structure. The design allows for a single 50-ohm feed point, simplifying station setup and minimizing feedline loss. The project provides specific dimensions and material choices, enabling a homebrewer to replicate the antenna. While inspired by L.B. Cebik's (W4RNL) theoretical work, this implementation focuses on practical construction techniques for a physical build. The resulting antenna offers directional characteristics suitable for DXing and contesting on 12m and 17m, providing an alternative to full-sized Yagis or compromise verticals, particularly for those with limited space.

G8ODE antenna project, where the 40m & Short 80m antenna was deployed as a sloping wire antenna using the 10M fibre glass fishing pole and a hook on the house's gutter-board

3 to 30 Mhz antenna analyzer schematic by YO3DAC / VA3IUL

A project for a 144 Mhz halo antenna

A slightly different 6M antenna project by N1GY, an Off center fed antenna for the 50 MHz.

Antenna that's simple, inexpensive lightwiight and easy to install

Members only techical pages about Sloper antennas

A receiving loop antenna project suitable for 150-430 KHz reception by Gregg van der Sluys

There are many kinds of satellite antennas that will get you on the birds and allow you to have lots of fun

KN4LF article about a 1/4 wave fan inverted L antenna for 80 and 160 meters band

Quagi 8el 70cm improved 13.77dBi by IK1HGE

An homebrew project for a 3 elements yagi monoband antenna for the 20 meters by 9M2MSO

This article describe a small single wire antenna running on the side of the building allow operations on 80 meters band

Antenna Warehouse provides a range of certified quality wire products for amateur radio and general communication applications. Their inventory includes Francis antennas, known for their robust construction, alongside the versatile Select-A-Tenna series. The company also stocks Solarcon 10/11 meter base antennas, catering to specific band requirements for 27-28 MHz operations, and various Wilson antenna models. Beyond product sales, Antenna Warehouse offers services such as antenna tower installation, repair, and removal. These services support the complete lifecycle of antenna systems, from initial setup to maintenance and decommissioning. The product selection emphasizes components for both fixed station and mobile installations.

The Windom antenna was widely used in the 1930s and is named after the amateur that wrote a comprehensive article about it

This technical note explores the application of **Moxon rectangle** antennas for WARC bands, specifically 17 and 12 meters, as compact directional alternatives to standard Yagis. It details three design approaches: a dual-band Moxon using open-sleeve coupling, a Moxon-Yagi combination, and a simplified 1.5 Moxon rectangle. The document provides specific dimensions in feet for aluminum tubing elements (0.75" and 0.5" diameter) for each configuration, along with projected free-space gain, front-to-back ratio, and feedpoint impedance (R+/-jX Ohms) across the respective band segments. Performance tables illustrate gain (dBi), front-to-back ratio (dB), and 50-Ohm VSWR for each design. The dual-band Moxon, despite its compact 7-foot boom, is not recommended due to extreme sensitivity to construction variations, leading to rapidly changing performance characteristics. The Moxon-Yagi combination, featuring a 17-meter Moxon and a 12-meter director-driver Yagi, is presented as a more practical and adjustable solution, offering stable performance with a 10-foot boom. NEC model descriptions are included for simulation in programs like EZNEC, NEC-Win Plus, AO, or NEC4WIN.

Bill Orr W6SAI ham radio techniques. Improving ground connection, computer analysis of the antenna, modelling sample antennas pdf file

The octoloop antenna is a length of 25 pair telephone wire inside an octagonal loop shield of 3/4 hard copper pipe

PA11019 Travel loop antennas, these antennas cover 6.300 to 29.200 mHz , handle 35 Watts and have a packing size of 43 cm, ideal for fieldwork, or mobile operations.

ON6MU Optimized 10 and 6 and 4 element UHF Yagi Antenna

This little antenna is cheap and easy to build, lightweight, and very functional on 2 meters and 70 centimeters by NA4IT

This article documents an unobtrusive antenna for operation on 7MHz, primarily for contacts with stations at up to 1000Km range.

OE1MWW monopole antenna made with common RG 58 or RG 213 coaxial cable

A direct drive ring radiator antenna for the 40 meters band by W6WYQ QST article.

G7LRR Amateur Radio Site,160m Helical Antenna

A windom multiband antenna project with pictures and diagram for the 6:1 balun

If you are looking for an easy antenna for your favorite band, you can't go wrong with an halfwavelenght dipole, all you need is 3 insulators and some wire

The N0KHQ Coax Square antenna, designed for 17 meters and built using RG-58 coaxial cable, presents an intriguing option for hams with limited space. L. B. Cebik, _W4RNL_, meticulously models and analyzes this array, clarifying its classification not as a modified Moxon, but as a distinct member of the "dual-coupled, 2-element, parasitic array" family. The design leverages the velocity factor of RG-58 (approximately 0.66-0.67) to achieve significantly shorter element lengths compared to full-size counterparts, resulting in a perimeter of 42 feet for the N0KHQ array versus 54 feet for a standard Moxon. _NEC_ modeling reveals the coax square's performance characteristics, including a forward gain of 5.6 dBi and a 23.7 dB front-to-back ratio on 18.118 MHz. While slightly less gain than a Moxon (6.0 dBi), its pattern exhibits Yagi-like nulls at 90 degrees, distinguishing it from the Moxon's wider beamwidth. The article also delves into the unique feedpoint considerations, explaining how the split braid and center conductor of the RG-58 driver effectively form a folded dipole, allowing for impedance transformation to achieve a good match for 50-Ohm cable. Despite its shortened elements, which inherently narrow the operating bandwidth, the coax square maintains satisfactory performance across the 17-meter band. The analysis emphasizes that while SWR curves are important, a holistic view of gain and pattern degradation across the band is crucial. This antenna is a viable solution for operators needing a compact, directional array, particularly for narrow bands like 17, 30, or 12 meters, where its high-Q performance is most effective.

W0OXB All-band Centerfed Zep Antenna 160m-6m

Calculate dimension for HB9CV directional antennas

Rhombic antenna experiments by Jelmer PA5R

Doublet multiband antenna for 80 to 10 meters band by

4 elements HB9CV antenna for six meter band by JA1HWO