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Constructing a Compact Low Cost Sprinkler Valve Antenna Launcher

Testing performances of indoor antenna. A comparison of a magnetic loop antenna vs a classic wire dipole done using wsprlite on 30 meters band.

High impedance amplifiers for shortened vertical antennas, Array matched and Optimized 15dB Preamplifier

Loop Antenna Basics and Regulatory Compliance for Short-Range Radio

W0IPL article on NVIS Antenna

How to build a QFH (Quadrifilar Helix Antenna) to download images from weather satellites. A complete tutorial on assembling QFH antenna at home with simple and common tools

Refurbishing a Cushcraft A3S, by George Szymanski, DU1GM

Magnetic Loop Antenna for 20/15m with Remote Tuning by George Szymanski

This antenna article is geared towards new Hams and antenna builders looking for a very inexpensive 6 band antenna that can be efficiently fed with 50 ohm coax without a tune

Since they were first described by the French mathematician Benoit Mandelbrot in the mid-1970s, repeating geometric figures known as fractals have fascinated computer scientists, mathematicians and graphic artists.

A directional active loop receiving antenna system by J A Lambert G3FNZ article published on Radcom in november 1982

The HyGain LJ-153BA a monoband 3 element Yagi, designed for the 15 m band 21.00 - 21.45 MHz

Discussion at eham about wire size used in wire antennas, and how it affects the gain of the antenna

A 38-foot Tristao Tower, similar to the U.S. Tower HDX538, was installed twice by the author, first in 1980 and then reinstalled in 1989. The resource details the challenges of self-performing heavy construction tasks like breaking concrete and digging a 3' x 3' x 6' deep footing, contrasting it with hiring professionals for the second installation. It highlights the financial and physical costs associated with DIY tower foundation work, noting a rebar cage cost of $65 in 1980 versus $150-$175 today, and the expense of tools for bending rebar. The content emphasizes the critical importance of obtaining building permits, recounting how a permit in Buena Park, California, nullified a neighbor's complaint about TVI. It also discusses the necessity of adhering to local building codes, such as the 1975 UBC and the subsequent 1985 UBC recertification requirement, which reduced the allowed antenna wind loading from 30 square feet to 20 square feet for the author's _KT34A_ Yagi. The footing depth also increased from 6 feet to 6.5 feet under the newer code. Practical advice includes hiring licensed contractors for specialized work, delaying antenna installation for a month after raising the tower, and verifying buried utilities before any excavation. The author provides specific examples of utility location services like _DigAlert_ in California, underscoring the legal and safety implications of neglecting this step. The narrative is grounded in personal experience, offering a realistic perspective on tower projects.

Description and simulation of two types of rhombic antennas, using the software 4Nec2: the simple bi-directional and the terminated directional rhombic antenna

A ten element ultra-lightweight yagi beam antenna for 144 MHz based on YU7EF design concept

Based on a simple project based on a 2 elements Yagi for 20m band, and then becomed a triband yagi with a open-sleeve feed system

A nice post on Make: on homebrewing a multiband antenna for amateur radio portable operations

Experiences with Loop antennas at G3YMC include some loop antenna tests and theory by G3LHZ

Here are 10 tips and truisms that every ham should know about antennas, by W20QI

Do you want to measure antenna impedance at resonance? With this Antenna Scope, you have a simple RF Bridge for getting started in an exciting part of Ham Radio, building your own Antennas that work well

A magnetic loop antenna for the VHF band, featuring a high gain that can be compared to a quarter wave vertical antenna

Quarter wave groundplane antenna for 2 meters FM by AA1PG

ITELITE manufactures omnidirectional, sector and directional antennas 900 MHz 2.4 GHz 3.5 GHz 5 GHz 5.8 GHz antennas.

The **KC0KJF** personal amateur radio page provides a collection of resources for fellow hams, particularly those interested in operations within southwest Missouri. It offers detailed listings for **Missouri repeaters** on both 2 meters and 70 centimeters, serving as a practical reference for local VHF/UHF communication. The site also includes information about the operator's station setup and antenna projects, such as a dipole and a bazooka antenna, which can offer insights into basic antenna construction and deployment. Beyond local repeater data, the page features links to the FCC Part 97 rules, essential for understanding amateur radio regulations. The operator, licensed as a Technician Class since April 16, 2001, shares his journey from Citizen's Band Radio to amateur radio, driven by a lifelong fascination with shortwave listening. This narrative provides context for the resource's focus on practical operating information and foundational regulatory knowledge. Additional content covers specific equipment like the 2-meter/70-centimeter Arrow Antenna, useful for hams considering portable or fixed station VHF/UHF setups.

Construct a compact, 20 meter rotatable dipole antenna of durable weather worthy components supported at a single point obviating the need for multiple supports and multiple support ropes crossing the yard.

The Patch Antenna Array was constructed and used for various satellite up and down links at my previous residence in Melbourne, Victoria from 2003 - 2007

The fan dipole antenna as an alternative to the paralled dipole antenna, to achieve a larger bandwidth and a better tuning by decreasing elenment influences.A project based on the W6HDG original concept.

Stop common-mode current when transmitting with an end-fed antenna. Unbalanced antennas are very prone to currents on the outside of the coax.

This article describes the design and simulation of a multiple dipole antenna for the HF band, using the software MMANA-GAL. The antenna will be designed to operate in the 10, 20, 40 and 80 m bands

Experimental Dual Band High Gain Flower Pot Antenna

An home made HF mobile multiband antenna inspired by the KM4IE HF 20 dollars antenna or the Texas Bugcatcher can work 75 to 15 meters band with an acceptable SWR.

A new, simple way to build the Eggbeater Antenna. This document introduces a new, simpler way to build the Eggbeater antenna. It also introduces a technically proper way to construct the Eggbeater antenna in order to achieve the best result.

Building a Resonant Feed line Dipole for 2 Meters

A NEC Model Comparative Analysis of Physical Orientation and Performance. The small magnetic loop is a useful compromise antenna for limited space and portability. For this reason, the magnetic loop antenna is a practical high frequency antenna solution for the restricted space of apartment dwellers

An off-center-fed sleeve dipole, made of CPVC and aluminum foil tape by KV5R

Presents the construction of a 2-meter **Skeleton Slot Yagi** stack, detailing the design process and practical considerations for VHF operation. The author shares insights from building and testing this antenna, emphasizing its performance characteristics for local and extended range contacts. The project outlines the specific dimensions and materials used, providing a clear path for other radio amateurs to replicate or adapt the design for their own stations. The resource covers the unique aspects of the Skeleton Slot radiator, explaining how its geometry contributes to gain and pattern control. It includes discussions on impedance matching and feedline considerations crucial for optimizing power transfer and minimizing SWR. The article draws on real-world testing, offering practical results that validate the theoretical design. This project serves as a valuable reference for those interested in custom VHF antenna solutions.

50MHz Collapsible 2 Element Mini Beam antenna, an overview the development of the 6MBA.

Pictures and description of a SteppIr vertical antenna setup in a small backyard using DX Engineering radial plates.

Post on a W3EDP experience by Bob Kellogg, AE4IC

The W3EDP is a 85 foot long wire and a 17 foot counterpoise. At N4KGL

50 MHz extended 6-7 element ZX-Yagi antenna. Dimensions for the 7 elements and information on performance of a 2 stacked antennas featuring a total max gain of 20.8 dBi

The **136kHz Vertical Antenna** at G3YMC employs a Butternut HF2V structure, standing 10m tall. It integrates a 6.5mH loading coil to achieve resonance, with a matching transformer for impedance adjustment. The antenna's configuration includes top loading via a 12m horizontal wire, enhancing capacitive impedance. Initial measurements indicated a high impedance of around 300 ohms, necessitating a transformer for a 50-ohm match. Despite challenges with ground losses, the vertical antenna has shown improved performance in specific directions, filling nulls present in the previous loop antenna setup. The tuning remains broad, with variations due to environmental factors affecting the matching. Ongoing adjustments and comparisons with the loop antenna will continue to refine its effectiveness.

This article is about a simple vertical end-fed-half-wave wire antenna for 10 meters that can be used in case of restricted space.

Modeling compact 160 meter antennas, inverted L, half wave dipoles and linearly loaded dipole

The G5RV junior Half Size antenna by kc8hps

A multiband HF Vee Beam antenna at VK5SW. If you're lucky enough to have the room, perhaps you may like to put up a multiband Vee Beam antenna for the HF bands.

kv5r 2 meter antenna

Experimentig magnetic loop antennas for VHF and HF by M0UKD

22 Different Wire Antennas for the 160 Meter Band, Random Length Radiator Wire, delta loop, loop antennas, off-centered antennas, sloper, dipoles, Z antenna, Zepp and Clothesline Antennas