Search results

Building a 2.4GHz vertical collinear omnidirectional antenna

This antenna is fed for vertical polarisation, to give a low angle of radiation for DX and also a nearly omni-directional radiation pattern.

Homemade 40 through 6 meter HF portable multiband antenna, an aluminium antenna construction article, with plan, drawings and photos

Dissects the internal components of the popular _Antron 99_ vertical antenna, revealing its unique design elements. The analysis details the construction of the coaxial phasing sections, which contribute to its multi-band performance across 10, 12, 15, and 17 meters. Observations include the use of fiberglass tubing for weather protection and the specific arrangement of conductors within the antenna's structure. The examination highlights the antenna's reliance on a series of coaxial stubs to achieve resonance on multiple HF bands without external tuning. This internal architecture provides insights into how the _Antron 99_ manages impedance matching and radiation patterns for effective DX operation. Further details cover the antenna's base mounting and overall physical dimensions.

Concise instructions on making a broadband helical antenna for 2.4GHz use, such as: 802.11b wireless networking 2.4GHz video links.

The page provides a project for an indoor wire antenna for the 7 MHz band, based on a design by F6CYV. It aims to help amateur radio operators lacking space to set up an antenna for 40 meters. The author shares their experience using the antenna inside an apartment, noting good reception of European signals and contacts with over 150 countries. The project details the materials and dimensions needed for the antenna, along with tips for optimal performance.

The antenna is nothing more than a simple 2.4 metre square loop drawing pinned to the internal brick wall of the spare bedroom. Yep, thats right, the inside wall of the spare bedroom - ideal for flat dwellers, hotel rooms or whinging neighbours, The loop has a simple switched inductance at the top of the square loop and uses a simple coaxial stub to tune the antenna. An additional variable capacitor placed across the feedpoint can be used to fine tune the resonance of the antenna, by Andy G0FTD

PDF file by QRP Expressions by By N. T. Len Carlson, K4IWL

Build a double bazooka coaxial dipole, broad-band dipole antenna

The Cubical Quad antenna is a popular choice among amateur radio operators due to its robust design and excellent performance characteristics. This resource provides essential scaling formulas that help determine the lengths of the antenna elements and the necessary gamma match values for various frequencies. The design is adaptable, allowing operators to optimize for gain or front-to-back ratio by adjusting the spacing between elements. The accompanying Excel files facilitate precise calculations, making it easier for both beginners and experienced hams to construct their own Cubical Quad antennas. In addition to the design formulas, the resource includes practical insights from the author, who has successfully built and utilized these antennas in various field events. The document outlines the tuning process for achieving minimum VSWR, ensuring optimal performance. With detailed illustrations and performance data, this guide serves as a comprehensive reference for anyone looking to delve into Cubical Quad antenna construction and optimization, enhancing their amateur radio experience.

How to Build a Dual-Band Antenna for 2M/70cm presentation PDF file

This article describes how an effective ground system can be produced for a short vertical antenna.

How do you fit a full length 160 meter antenna into a 40 foot deep yard?

Easy download your free high quality desktop image about amateur radio station and antenna

A 27 pages pdf file revealing secrets of the cobwebb or cobweb multiband antenna with many pictures and assembling details. A great document that can guide you in making your own cobweb aerial.

Magnetic loops are a compromise antenna and performance will be down on a full size-wire antenna particurlarly on lower HF Bands. This article compare this magnetic loop with a full-sized wire antenna on 80 meters by VK3YE

Conejo Valley Amateur Radio Club, article edited by Rory Eikland, KG6HCU and Ken Larson, KJ6RZ, they have had excellent experience building and using J-Pole antennas, and share their experience on planning VHF and UHF Jpole antennas.

Ham radio dealer based in germany offer RF power amplifiers, from Alpin and SPE, antennas, RFI suppression products and GSM GPRS products

This drawing shows a simple 10 meter wire J-pole antenna designed for 28.4 MHz. It is a vertical, end-fed Zepp-style antenna made from common materials and intended for easy home construction. The main radiating element is a straight length of stranded copper wire, either 14 or 18 gauge, cut to about 16.5 feet. At the top, the wire is supported by an insulator, allowing the antenna to be hoisted vertically. The matching section is made from 450-ohm ladder line, approximately 7 feet 9.5 inches long, and shorted at the bottom. This matching stub transforms the impedance so the antenna can be fed with coaxial cable. The feed point is tapped about 6 inches above the bottom of the stub, with the shield and center conductor connected at the proper points. A choke balun is formed with five turns of RG-58 coax in a 4-inch diameter loop to help reduce unwanted RF on the feed line. The drawing notes that this antenna has about 0 dBd gain, similar to a dipole, but offers an omnidirectional pattern and low-angle radiation when installed high. Its main advantage is practical performance, simple construction, and effective coverage for 10 meter operation.

Concentric Open Loop Antenna Fed Off-Centre similar to the cobwebb antenna but resonating on 20-17-15-10 meters band

Modified version of the Telerana antenna which was orginially featured in the July 1979 issue of QST. The array is suspended within a framework made of fiberglass poles emanating from a central hub with the ends tied together with light weight rope around the perimeter. 10-15-20-30-40 meter band coverage

Over 30 distinct shortwave (SW) receiver models are reviewed, offering insights into their performance, features, and user experiences. These evaluations, contributed by readers of the Usenet newsgroup **Rec.radio.shortwave**, cover a wide array of portable and tabletop radios, including popular units like the Grundig YB-400, Sony ICF-SW77, and various Realistic DX series models. Each review details aspects such as frequency range, tuning steps, SSB functionality, antenna performance, and construction quality, often comparing them to other receivers or ham transceivers like the Icom 725. For instance, the Grundig YB-400 review highlights its 144-30000 kHz AM/SSB coverage, direct keypad entry, and 40 station memories, noting its useful narrow bandwidth and tone switch for adjacent signal separation. It also discusses the **SSB mode** stability and the limitations of its 1 kHz frequency resolution for precise zero-beating. The review further details antenna performance, including the effectiveness of the built-in whip, the provided 7m reel antenna, and the potential for overload with larger outdoor antennas. Other reviews delve into specific issues, such as the Sony ICF-SW77's frequency display inaccuracies and timer malfunctions, or the Realistic DX-342's compact size and surprisingly good MW DXing capabilities despite its analog tuning. The collection provides practical, user-generated feedback on sensitivity, selectivity, audio quality, and ergonomic features, helping shortwave listeners understand the real-world performance and quirks of these receivers.

The PringlesCantenna is an ultracheap Yagi-type directional antenna that can be built for under $10. The original Pringles Yagi was designed by Andrew Clap.

Online calculator for Logarithmic Periodic Dipole Antenna LPDA

Selecting an appropriate antenna system for shortwave broadcasting involves evaluating various types based on performance, cost, and operational parameters. This resource details the critical specifications for broadcast antennas, including average and peak power ratings, directivity, takeoff angle (TOA), horizontal beamwidth, and gain, emphasizing that a 100-kW transmitter requires an antenna rated for 150 kW average and 400 kW peak. It clarifies that low TOA signals travel thousands of kilometers, while high TOA is for local coverage, and nearly all modern shortwave broadcast antennas are horizontally polarized. The article explores specific antenna types, such as Log-Periodic Antennas (LPAs), which offer wide frequency ranges (e.g., 2-30 MHz) and directional patterns with 11 dBi gain, costing from $20K to over $100K for multi-curtain versions. Dipole arrays, also known as curtain antennas, are prevalent in international broadcasting, featuring steerable beams (±15° and ±30°) and mode-switching capabilities to alter TOA, with high/low pairs costing over $1 million. Fan dipoles are noted for omnidirectional patterns, smaller size, and lower cost for low-power applications, while rhombics, though simple, require resistive termination and incur several dB of I2R losses. Balun considerations are crucial, as most communications baluns are not rated for the higher average and peak powers of AM broadcast transmitters. Modern shortwave antennas utilize durable materials like Alumoweld wire rope for radiators and support elements, avoiding copper, fiberglass, or materials prone to stretching or deterioration. Feeder systems for high-power stations often require tapered-line baluns to convert 50-ohm unbalanced power to 300-ohm balanced for connection to the antenna.

All copper J-Pole antennas for sale. 6 meter, 2 meter, 222 MHz, 440 MHz, LPFM, Marine, GMRS. Includes a construction plan in pdf format if you wish to build your own antenna.

Over 40 years of experience inform the reviews and commentary presented on Dave's Radio Receiver Page, covering a wide array of radio receivers and transceivers. The resource details specific models such as the **ICOM IC-R8600** SDR Communications Receiver, which is lauded as Icom's best wide-band receiver, even surpassing the IC-R9500 in performance. Other notable reviews include the ICOM IC-7300 HF Transceiver, highlighting its direct sampling SDR technology and spectrum scope capabilities, alongside numerous models from Japan Radio Co. (JRC), Kenwood, Yaesu, and various portable shortwave receivers. The content provides practical insights into the performance and characteristics of each radio, often drawing comparisons between models. For instance, the early issues with the AOR AR7030 receiver's Bourns mechanical encoders are thoroughly documented, including AOR's eventual switch to higher-quality Alps encoders. The page also features reviews of antennas like the MFJ-1026 Noise Canceling Signal Enhancer and various power supplies, offering a holistic view of radio monitoring setups. The author's "2 ear / 2 eye method" emphasizes real-world listening experiences over laboratory measurements, providing a unique perspective on equipment utility.

Basics and principles of the HB9CV antenna by Rudolf Baumgartner. This antenna join electric advantages of the two elements direct feeded aerials with the mechanical advantages of the Yagi antennas, in French.

What is the best WiFi antenna for me? Looking for a range extender antenna for your WiFi system. This article will help in choosing the correct antenna for your system

Manufacturer of communications antennas, bandpass filters, RF combiners, receiver multicouplers, diplexers, duplexers, RF connectors, RF circulators, RF isolators, RF couplers and SWR meters

F6EZX presents a detailed account of constructing a compact, multi-band _Levy antenna_ for portable holiday operations, specifically addressing issues with local QRM from a previous _Deltaloop_ setup. The article outlines the design criteria, including multi-band operation on 40m, 30m, 17m, 15m, 12m, and 10m, a symmetrical configuration to reduce interference, and a low take-off angle for DX. Construction involves 2x 10.3m radiating elements and a 15.3m open-wire feeder (ladder line) with 7cm spacing, made from 1.5mm2 copper wire and foam pipe insulation spacers. Theoretical calculations, referencing F9HJ's "_Les antennes Levy_" book, guide the determination of element lengths and feeder impedance characteristics, aiming for a good match across bands with a commercial antenna tuner. Initial field tests with the _VCI Vectronics VC300DLP_ tuner showed a 1:1 SWR from 80m to 10m, with some difficulty on 17m. The antenna, mounted as a 45-degree slopper with the high point at 12m, successfully facilitated DX contacts to South America, particularly Chile and Argentina, suggesting a lower take-off angle compared to the previous Deltaloop which favored Brazil. The Levy antenna significantly reduced TVI/RFI, attributed to its improved symmetry and greater distance from the QRA. While signal reports on 15m and 20m were 1-2 S-points lower than the Deltaloop, its performance on 40m and 30m was comparable, fulfilling the design goals for a portable, low-cost, multi-band solution.

The W8JK is a famous and effective DX antenna, first built by John Kraus, W8JK, in 1937. A Beam antenna with two parallel dipoles driven with opposite phase, with a close spacing of an eighth of a wavelength.

Antennas that use a combination of vertical and horizontal polarisation.

A shortened multiband antenna, about 23m long, for 80m - 10m bands with a low SWR (<1.3) on 80m and 40m, and < 3 till 10m. Bandwith on 80m is 300kHz

Notes on bazooka antennas by Katunk: a portable field antenna, sometimes called the double bazooka or a coaxial antenna.

46ft multi-band antenna for small gardens. Works well on 80m. An excellent DX performer and is an ideal replacement for your half size G5RV

Buildin a VHF Jpole antenna with detailed pictures

Portable Vertical Antenna for 75m and 40m featuring Low radiation angle for DX, easy to install and to match 50 ohms

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

6m to 40m EndFed Half Wave Antenna project produces an inexpensive, multiband, end fed HF antenna matchbox that is quick and easy to setup and use.

Manufacturer of Fibreglass Whip Antennas, Low and mediun Frequency, HF and VHF Antennas Specialized in the design and manufacturing of a full range of Beacon (MF), AM Broadcasting 540 - 1700 KHz, HF 1.7 to 30 MHz, VHF 30 to 156 MHz and UHF 200 to 500 MHz antennas.

7 dB for 7 Bucks, a 2 meter beam antenna for the cost of a fast food meal!

An easy to build antenna for ground reception of NOAA weather or amateur satellite signals. Double cross antenna by Gerald Martes

A base station antenna you can easily build for 146,220 or 440 MHz, with performance similar to a J-pole but smaller and less obstrusive

Manufacturers and distributors of coaxial surge protectors, coaxial switches, insultators, HF fixed wire antennas

Build your own home made Antenna Analyzer with an arduino micro, or a cheeper one with a pic processor

Amateur Television (ATV) operations, particularly within the Arizona region, require dedicated resources for technical information, operational guidance, and community engagement. This club provides a focal point for hams interested in transmitting and receiving video signals on amateur bands. Members engage in local ATV repeaters, participate in technical discussions, and share knowledge on video modulation schemes, antenna designs, and station configurations. The club supports activities ranging from local simplex contacts to wider area repeater usage, fostering skill development in this specialized mode. The organization maintains a roster of club officers and offers membership opportunities to local amateurs. It also curates offsite links to other ATV resources, expanding the knowledge base available to its members and the broader amateur community. The club's emphasis on ATV helps propagate interest and technical expertise in a mode that combines traditional RF engineering with video technology.

Tombone VHF antenna for 146 MHz ad designed by YB8EIP

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.

A 40 80 dipole antenna design by WA6ESC PDF File