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Query: pdf antenna
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Constructing an HF End-Fed Half-Wave (EFHW) vertical antenna, the resource details the winding of a monoband matching unit, inspired by _AA5TB_, designed to provide a 50 Ohm impedance match without a ground plane or antenna tuner. It specifies the use of a _T200-2_ ferrite core for the transformer, outlining the 13-turn secondary and 2-turn primary winding process with enamelled copper wire. The document also describes the integration of a coax capacitor, whose length is critical for tuning and varies by band, with specific starting lengths provided for 20m, 17m, 15m, 12m, and 10m operation. The practical application section guides the builder through tuning the antenna using an antenna analyzer, emphasizing the iterative process of spacing secondary windings and trimming the coax capacitor to achieve resonance at the desired band frequency. It highlights the antenna's low angle of radiation, beneficial for DX, and claims up to 2 S-points improvement over a _G5RV_ or similar doublet when used as an omnidirectional vertical. A comprehensive shopping list, including specific part numbers from _Rapid Electronics_, is provided, along with advice on selecting fiberglass fishing poles for support and suitable antenna wire. -
A Portable VHF-UHF Roll-up J-pole Antennam that resonates on both bands but actually performs as a half wave radiator on both bands -
A homemade Magnetic Loop antenna from a spare 3m length of RG213 working from 30m to 15m with a 130pF tuning capacitor -
G8OFZ multi-band antenna for 80-10m, this antenna appears to be a derivative of the Doublet and the Classic G5RV -
This PDF document, authored by KT4QW in October 2004, details the construction and modeling of a dual-band, horizontally polarized hanging rectangular loop antenna for **10 and 17 meters**. The design, adapted from *The ARRL Handbook*, utilizes _NEC4WIN95_ software for scaling and optimization, targeting a 50 ohm feedpoint impedance. The resource includes a bill of materials, step-by-step construction instructions, and a discussion of the antenna's radiation characteristics. It presents NEC-generated elevation and azimuth patterns, comparing the loop's performance to a half-wave horizontal dipole at the same height and frequency. The 17-meter element is centered at 18.140 MHz for low SWR across the phone band, while the 10-meter element is centered at 28.500 MHz. Construction involves 14-gauge stranded copper wire and Schedule 40 PVC spreaders, with the total wire length calculated by the formula: Length in feet = 1005/MHz. The feedpoint impedance can be adjusted by modifying the rectangular aspect ratio. The document specifies hoisting the antenna to at least a half-wave above ground for testing. It notes that a balun was tested and found to have no measurable effect on SWR or radiation characteristics. A 2-meter scale model is presented to illustrate the physical design, and a "rotator" string is incorporated for directional adjustment up to 90 degrees. -
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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. -
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 -
Antenna that's simple, inexpensive lightwiight and easy to install -
A receiving loop antenna project suitable for 150-430 KHz reception by Gregg van der Sluys -
Bill Orr W6SAI ham radio techniques. Improving ground connection, computer analysis of the antenna, modelling sample antennas pdf file -
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. -
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 -
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Doublet multiband antenna for 80 to 10 meters band by -
The Arrow Antenna is a design classic: it combines light weight, compact design and functionality in a single package for operating FM dual band satellites such as AO-27, UO-14, SO-41 and SO-50 -
Theory, Modeling, and Practical Applications By W5JCK, presentation in PDF File. This presentation focuses on Near-Vertical Incidence Skywave (NVIS) antennas, which are crucial for short-range radio communications, particularly in military and emergency contexts. It explores NVIS theory, antenna models, and installation criteria while debunking common myths about reflectors. Key topics include usable frequency bands, optimal installation heights, and the impact of soil quality on performance. The presentation outlines the best bands for daytime and nighttime use, emphasizing the importance of understanding propagation characteristics to enhance communication effectiveness within 200 to 300 miles. -
Adalet wireless document on antenna basics in a four pages pdf file -
An easy to build single wire antenna for 160 and 80 meters with a better than 2 to 1 swr across the 80 meter band by K5GP -
Here is how to adjust this popular tuner circuit so it transfers maximum power to your antenna without going snap -
A multiband antenna that can work from 80 to 10 meters in this illustrated docuemnt by G8ODE -
A 40 80 dipole antenna design by WA6ESC PDF File -
By ON4CFC Pascal, describe how to build a Sperrtopf or Sleeve antenna for the 144 Mhz, PDF File by antennex -
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. -
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An easy to build single wire antenna for 160 and 80 meters with a better than 2 to 1 swr across the 80 meter band -
Illustrates the specific wiring and configuration steps required to interface an SGC-230 Smartuner with an Icom IC-706 HF/VHF/UHF transceiver. The document details the necessary connections for power, control, and RF signal paths between the two devices, ensuring proper impedance matching and automatic antenna tuning functionality. It specifies the pin assignments for the IC-706's ACC socket and the SGC-230's control port, crucial for successful integration. Outlines the operational considerations for the combined system, including initial setup procedures and potential troubleshooting tips for common connectivity issues. The resource presents a clear, diagrammatic representation of the interconnections, which aids in visual comprehension of the required cable fabrication or modification. Covers the specific settings within the IC-706 menu that need adjustment to enable external tuner control, such as the 'TUNER' function and other relevant parameters. This ensures the transceiver correctly communicates with the SGC-230 for efficient antenna tuning across various amateur bands. -
This is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It is a dipole fed off center with a 4:1 current balun at the offset feedpoint. The antenna shown covers 80, 40, 20 and 10 meters with 15 meters and WARC bands -
The AMRAD Active LF Antenna. You can tune into LF activity with this easy-tobuild and erect active antenna. As a bonus, you get MF and HF coverage, to not to mention world-class performance -
A different approach can help you optimize attic-bound aerial by W6HPH -
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A monoband end-fed half wave for 10m, 20m or any other HF band, includes a PDF with detailed information to build your own monoband or multiband antenna -
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The Classic Multiband Dipole Antenna QST article. The open-wire feed line dipole antenna is easy to install and offers surprising performance on several bands. You can install it in almost any configuration; it does not have to be strung in the traditional horizontal flat top -
40 meter vertical antenna construction, a shortened easy-to-build vertical, with no-radials, made from surplus military camouflage poles -
A portable 4 elements quad antenna for 144 MHz, 9 to 10 DBd forward gain, 30 DB front-to-back ratio, and 33 DB front-to-side ratio -
The document details the construction of a compact, two-element Quad antenna specifically designed for the 10, 12, and 15-meter HF bands, featuring a single feedline for all three bands. It provides specific dimensions for the driven element and reflector loops, along with boom length and spacing, emphasizing a **0.12 wavelength** spacing between elements. The design incorporates a gamma match for impedance transformation and uses PVC tubing for spreaders, aiming for a lightweight yet robust structure suitable for portable or restricted-space operations. Performance measurements indicate a forward gain of approximately **6 dBd** on 10 meters and a front-to-back ratio of _20 dB_ on 15 meters, demonstrating effective directivity and signal rejection. The antenna exhibits a VSWR below 1.5:1 across the target bands, achieved through careful tuning of the gamma match. This compact Quad offers a viable directional solution for HF DXing and contesting, particularly where full-size Yagis are impractical. -
Article on radiation patterns of small loops, equivalent circuits of loop antenna, small loops as receiving antennas, ferrite loops -
Choosing the right antenna for you, by Lewis G. McCoy W1ICP -
A 5/8 wavelength mobile whip antenna for 2 meters can be constructed from a 5-foot CB helical whip, requiring the removal of original wire and installation of a new radiating element made from coax braid. The design incorporates an 8-turn loading coil with 5mm spacing, fabricated from the original whip wire, and utilizes approximately 1400mm of RG-58 coax braid for the radiating element to enhance flexibility and bandwidth. Final whip length is approximately **1350mm** from base to braid end, with tuning adjustments made by trimming the braid. Dual-wall 12mm heat shrink, such as _Jaycar WH5643_, is recommended for weatherproofing and stabilization, costing around $4.50 per 1200mm length. Achieving a 1.1:1 VSWR may not be feasible; a 1.5:1 VSWR is considered acceptable. Optimal mobile mounting is centered on the vehicle roof to minimize radiation pattern variations. -
W3DZZ trapped multi-band antenna, exposed in this practical wireless article -
Simple, easy to build, low cost, compact, multiband By Robert Wilson, AL7KK -
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. -
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Gap Titan DX Antenna manual. This is an enhanced version of the common Gap Titan DX Manual document you can download from other sites. This manual is in PDF Format. -
This project produces an inexpensive, multiband, end fed HF antenna matchbox, quick and easy to setup. This project creates a trifilar wound, 9:1 UNUN toroid matching transformer. Handles 100W and need an antenna tuner. -
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Helical antennas have long been popular in applications from VHF to microwaves requiring circular polarization, since they have the unique property of naturally providing circularly polarized radiation. Paul Wade W1GHZ -
This HALO design is not ground dependent and can be mounted atop a section of PVC.