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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

Outbacker mobile and portable antenna systems are slim line, highly efficient, single whip multi bond antennas for vehicular and limited space portable applications.

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

Cheap and EZ to build Bi-Directional VHF & HF antennas with gain

CB Radio, and 10 meters antennas manufacturer

W1YW QRZ page dedicated to fractal antennas

Article on radiation patterns of small loops, equivalent circuits of loop antenna, small loops as receiving antennas, ferrite loops

All bands HF mobile antennas manufacturer

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.

Here is a way to ease assembly and balancing of a large antenna. The elements and boom are assembled separately in most cases. Once they are all together set up 2 tripods in the assembly area and put the boom on them.

A Bulgarian bazooka antenna project by LZ2ZK

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

Plans and drawings of common amateur radio antennas, like jpoles, copper cactus, super jpole, omnidirectionals and quads

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

Slot antennas explained

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.

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.

Many antennas function because of common mode currents, rather than working in spite of them. Two popular examples are CFA and EH antennas. Another recent example, appearing in Antennex's compact antenna articles, is a thick stub "vertical" with no counterpoise.

Phased vertical antenna system in french

The page discusses Axial-Mode Helical Antennas, focusing on turning helical antennas over perfect ground and modeling helices in NEC-2 for optimized design. It covers topics such as high-gain performance, broadband, impedance matching, radiation pattern, feedline, balun, near field, far field, and DIY applications.

A german documento on magnetic loop antennas

About HF Wire Antennas for field day or any day a basic wire antenna article

A moxon antenna project for 70 cm band, test and results of this popular antenna model applies to UHF bands.

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.

By Guy, de ON6MU, At VHF, both the 1/4-wavelength monopole and the 5/8-wavelength monopole antennas are widely used.

W4ZT used this antenna for Field Day and other portable applications. He built them for all bands between 160 meters and 6 meters. You can make them easily using whatever wire you have available and make the insulators from scrap plastic

There is considerable confusion as to what exactly a multiband vertical antenna is. The confusion concerns the method of feed, how much mismatch one can expect, how many radials are required, how the particular antenna is built for multiband use, plus some other points.

Lowering an NVIS or N.V.I.S. antenna very close to the ground enhances NVIS operation

A Quad Loop antenna for 17 meter band

The G5RV JR cover 10-40 meters band a project by PU2OKE

With over 20 years of experience, Proyecto 4 operates as a specialized ham radio retailer in Madrid, Spain, providing a diverse inventory of transceivers, antennas, and related accessories. The store features popular models like the _ICOM IC-705_ and _ICOM IC-7300MK2_, alongside Yaesu transceivers such as the _FTX-1 Optima_, which delivers 100W on HF and 50W on V/UHF bands. The product range includes mobile and portable antennas, such as the D-Original DX-NR770HB, offering 3 dB gain on 144 MHz and 5.5 dB on 430 MHz, and the Diamond RH-770 with a BNC connector. CB radio enthusiasts can find the Anytone CB SMART II AM/FM transceptor and the Telecom LS145 mobile antenna, rated for 500W and 4 dB gain on 26-30 MHz. Proyecto 4 emphasizes its in-house technical service, inviting customers to visit their laboratory for repairs and technical consultations via sergio@proyecto4.com. The store also highlights customer reviews and offers promotions like Yaesu Cashback, providing savings up to 100€.

Quad and loop antennas comparisons, evaluating the impedance and gain of both antennas and considerationso n horizontal loop antennas for low bands by PA0FRI

Electronically controlled HF antennas. General coverage. Top features on all ham bands. Very advanced materials and state of the art technology.

The rhombic antenna is a diamond-shaped antenna, suspended between 4 masts.

One of the most useful antennas in the repertoire is the Marconi or quarter wave grounded vertical antenna. Its invention made it possible to halve the length of antennas, simplifying communications, especially at HF and below.

DK7ZB- Moxons with Aluminium Tubes, plans for moxon antenna for 6 10 12 15 meters

The industry standard in all antenna products

Basic information on the folded dipole antenna

An old post by John Doty about effects of noise in longwire antenna.

Cheap Antennas for the AMSAT LEO Kent Britain WA5VJB

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

Group with thousand of memebers focused on NVIS antenna

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

Ham radio antennas and electronics, specialized in 1/2 wave dipole, OCF dipole, windom, full wave loop, end fed, inverted L, portable end fed antenna, long wire, SWL antenna, fan dipole, multiband dipole, G5RV and military antennas.

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.

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

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

Comparison chart for low-band receiving antennas