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A very basic guide to antennas concept. Explain the usage of dummy load, basic antennas like dipole o j-poles.

This ia a home built Magnetic loop antenna which was used by G3BGR, indoors on 7,10 and 14Mhz. The basic idea was in Radcom 1986

The basics of what is a discone antenna for wide band or bandwidth omnidirectional applications.

The Yagi-Uda antenna, information on basic design, project and measure of Yagi-Uda antenna, include free repository/sample of beam antenna.

Experiments on HF antennas for restricted spaces. In this article author experiments antennas for 80-10 meters band having just a very small garden and several restrictions. Basic antennas consists of laded multiband dipoles and fan dipole antennas

A home made antenna tuner based on the W6JJZ basic concept that ,atches balanced loads without the use of lossy baluns, can provide band-pass filtering and harmonic attenuation.

The grounded half loop describe in this article is basically a half wave length wire on 80 Meters. The 80M grounded half loop antenna, inspired by a 1984 QST article by SM0AQW, is a compact solution for limited spaces. Comprising a 127-foot wire fed against ground and supported by radials, it balances performance and practicality. Despite compromises in length and proximity to structures, the antenna delivers strong signal reports and effective multi-band tuning using an SGC 237 antenna coupler. Ideal for CW operation, it offers low SWR on 80-10M, though noise levels and safety considerations warrant attention. This versatile design excels in constrained environments.

Some basic antenna information for the newcomer

Dish antenna and its theory and design for high performance applications such as satellite transmission and reception as well as microwave links. Parabolic Reflector Antenna: Dish Antenna The parabolic reflector antenna which is often called the dish antenna provides an antenna solution applicable for VHF and above where high gain and directivity are needed for all type of radio communications and radio reception.

Demonstrates various practical amateur radio projects and technical discussions through video episodes. One episode details cutting and retuning a _1/4 wave shorted stub_ from 101.7 MHz to 107.5 MHz to safeguard a transmitter's driver stage, alongside insights into advanced _160-meter antenna systems_ like eight-circle arrays and beverage antennas. Another segment covers upgrading firmware on an _ATS-20+_ receiver using AverDudes for improved display and functionality, and a detailed guide on using D-Star DR mode on an _ICOM ID-52A_ for international repeater programming. Additional content includes a deep dive into _OpenHamClock_ as a potential replacement for the HamClock project, updates on _Raspberry Pi 5_ running Trixie OS, and a review of the Choyong LC90 Internet radio with AI integration. The series also features "Ham College" episodes, which meticulously prepare viewers for the Technician Exam by covering topics such as antenna and transmission line measurements, SWR interpretation, and the functions of basic electronic components like rectifiers, relays, and transistors. Practical advice on coaxial cable characteristics, dummy loads, and proper soldering techniques is also provided.

Radio wave propagation, Principles of transmission lines, Antennas

About the basics of what is a discone antenna for wide band or bandwidth omnidirectional applications

Antenna for limited space, made from 24AWG wire helically wrapped around the top element of a 3-element cane pole, is basically a fully-loaded vertical and performance are limited and should represent the last resort for extreme cases.

This article includes an online calculator for a 3 element Yagi Antenna. The formula and basics theory of Yagi Antenna are also explained with examples.

Designing and constructing portable wire antennas for HF operations, this resource explores several configurations including the _foldback dipole_ for space-constrained setups and an inductively shortened dual-band dipole for 20m and 40m. It details the calculation of inductance for shortened elements, providing a Visual Basic 6.0 program screenshot that illustrates determining coil parameters like turns and length for a **25.5 uH** inductor. The document emphasizes practical considerations such as adjusting wire lengths for optimal SWR, noting that a dual-band dipole achieved SWR below 2:1 on both 20m and 40m, with careful adjustment bringing it under 1.5:1. Further, the resource describes a half-wave antenna matched with a coaxial stub, a method often referred to as the _Fuchskreis_ in German amateur radio circles, to transform the high feedpoint impedance to 50 Ohms. This monoband solution, for a 20m application, uses a stub length of **2.98m** (0.216 lambda multiplied by coax velocity factor) and a shorted stub of approximately 48cm. The coaxial stub design is highlighted for its resilience to ground proximity, allowing it to be rolled up or laid on the ground with minimal SWR impact, making it highly suitable for portable QRP operations.

Loop Antenna Basics and Regulatory Compliance for Short-Range Radio

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.

About basics of the horn antenna used for many rf microwave antenna applications.

This is a presentation used at OVARC on the LindenBlad antenna construction. The presentation cover several topics about this antenna, from the basic antenna design, to the guide on how to contruct a custom lindenblad antenna for the 2 meters band and and 70 centimenters band.

Simple 6 Metre DX Antenna based on an article by LB Cebick in QST May 2002 on a Quad Turnstile antenna. This antenna is basically two full wave loops mounted at right angles fed 90 degrees out of phase to produce an omni-directional horizontally polarized pattern

Basic guidelines for proper placement of an amateur radio mobile antenna

The current, the voltage, the impedance, the bandwidth, the polarization, and how the earth influences the famous radiation pattern.

Article by K0BG on automatic antenna couplers, erroneously called antenna tuners with reviews of popular tuners and basic concepts.

Operating the AO-51 amateur radio satellite with a handheld transceiver (HT) presents a practical entry point for newcomers to satellite communications. This resource details the necessary steps and considerations for making basic contacts, focusing on accessible equipment. It covers fundamental concepts such as _Keplerian elements_ for satellite tracking and the importance of understanding Doppler shift effects on both uplink and downlink frequencies. The tutorial outlines a straightforward approach to satellite passes, emphasizing the use of readily available gear. It provides insights into antenna orientation and timing for successful two-way communication. The content aims to demystify satellite operation, enabling operators to achieve their first **AO-51** contacts with minimal specialized equipment. Key aspects include frequency management and basic operational techniques.

This article serves as a beginner-friendly guide to constructing a simple VHF dipole antenna for 2 meters, perfect for novices in the hobby. With an emphasis on affordability and simplicity, it explains the basics without overwhelming technical details. Recommendations for coaxial cable and mounting methods are provided, offering practical solutions for effective communication. By following these instructions, novices can build a functional antenna without breaking the bank.

An easy to build and extremely high performance antenna, works perfectly on all HF bands 3.5-28 MHz with some compromises, it is basically an half wave dipole for 40-80 meters, an LC circuit or trap 40 meters allows you to use a single radiating element.

An interesting presetnation full of usefull tricks to correctly design and build 23 cm Yagi using simple tools. The basic design of the antenna presented in this document is taken from the original DL6WU Yagi Design published in 1982

An overview of the basics of the horn antenna used in RF microwave applications.

Summary, tutorial about the basics of what is a waveguide and the basic waveguide theory.

Antenna gain and directivity explained in this article at radio electronics antenna pages

An article that explain with simple concepts and basic theory the correct usage of antenna tuners. It covers some aspects of common questions newcomers have on what antenna tuners are for, and what antenna tuners will never do.

Distributed Antenna Systems technology used for gaining better coverage and using a lower power.

Online calculator for J-Pole antennas. The J-pole antenna consists of a short and a long vertical pole with a feed point near the bottom. The antenna looks like the letter J, hence the name J-pole antenna.

Smart antennas or the adaptive antenna array and smart antenna technology used with SDR, cognitive radio, MIMO, and other new technologies.

Explains the annual Jamboree on the Air (JOTA) event, a global amateur radio gathering for Scouts and Guides. This activity connects young people worldwide through ham radio, fostering international friendship and introducing them to radio communication technology. Participants use various amateur radio bands and modes, including HF, VHF, and digital modes like FT8 and JS8Call, to make contacts with other JOTA stations and learn about the hobby. The ARRL provides resources for Scout leaders and amateur radio operators interested in hosting a JOTA station, including guidelines for setting up temporary stations, safety protocols, and educational materials. The event typically occurs on the third full weekend of October, aligning with the World Organization of the Scout Movement's (WOSM) global schedule. JOTA emphasizes hands-on experience with radio equipment, antenna theory, and basic operating procedures. It serves as a significant public service opportunity for hams to engage with youth and promote the educational aspects of amateur radio.

A summary, overview or tutorial covering the basics of Meteor Scatter or Meteor Burst Communications, a form of radio signal propagation often used at VHF.

Article on antenna feed impedance and the importance of matching RF andtennas to feeders, including notes on Radiation resistance, loss resistance, and efficiency are also detailed.

Basic priciples of Yagi antennas and its variations like Quagi antennas, Quad antennas includes pictures, drawings and online calculators by KN9B

Utility-Driven Tradeoff Analysis, if you want to geto on the microwave bands , you will have to choose the proper antenna for your operating conditions. How to decide is not always easy, and you may also decide to build your own antenna.

About antenna or aerial resonance and bandwidth and the impact of RF antenna resonance and bandwidth on radio communications systems.

A light and sturdy Quad for 10 and 15 meters. Basic Quad antenna design considerations. Building and assembling a dual band HF QUAD antenna, designing and joining cross-arms and boom, assembling spreader and element wire installation notes. QST article.

Basic anctenna theory, general information on antennas

Cmpter Electronics specializes in the design and manufacturing of RF coaxial connectors, RF adapters, and RF cable assemblies, serving diverse applications across datacom/telecom, automotive, instrumentation, aerospace, and defense sectors. Their product line includes RF coaxial terminations, attenuators, and waveguide to coax adapters, catering to specific needs in radio frequency systems. The company also offers precision adapters and connectors, alongside glass beads and test cable assemblies, indicating a focus on high-quality components for demanding RF environments. Their resource center provides valuable information, including an "RF Made Simple" section and a product catalog for download, which assists engineers and technicians in selecting appropriate components. The product named system helps in identifying specific parts, streamlining the procurement process for complex RF solutions. With a comprehensive range of RF coaxial cables and related tools, Cmpter Electronics positions itself as a key supplier for critical infrastructure requiring reliable signal integrity. Their offerings support a broad spectrum of RF applications, from basic connectivity to advanced test setups.

Basic dipole antennas by KN9B

Sixty-meter repeaters typically use a 1 MHz frequency separation between input and output, while 2-meter repeaters commonly employ a **600 kHz** split and 70-centimeter repeaters use a **5 MHz** offset. This article details the fundamental technical principles of amateur voice repeaters, explaining how they extend VHF/UHF communication range by receiving on one frequency and simultaneously retransmitting on another. It covers essential components such as receivers, transmitters, filters, and antennas, often situated on elevated locations for optimal coverage. The resource delves into the critical challenge of _desensing_—where the repeater's strong transmit signal overpowers its own receiver—and the engineering solutions employed, including antenna separation and the use of high-Q cavity filters. It also explores various control and timing systems, from basic squelch activation to more sophisticated microcontroller-based boards that manage functions like voice identification, time-out timers, and fault protection. Different access methods are discussed, including open access, toneburst, CTCSS subtone, and DTMF, each offering distinct advantages for managing repeater usage and mitigating interference. Furthermore, the article examines repeater linking, both conventional RF methods and modern internet-based solutions, highlighting how linking expands coverage and promotes activity across multiple repeaters or bands. It introduces less common repeater types such as 'parrot' repeaters, which use a single frequency and digital voice recording, and linear translators, capable of relaying multiple signals and modes simultaneously across different bands, often found in amateur satellites.

A home made portable vertical antenna, that with a single 1/4 wave counterpoise wire is possible to achieve less than 1.5:1 SWR on 40, 30, and 20 meter bands. It is basically a center load, shortened ground plain vertical antenna.

An article describing basic concepts of antenna radiation, and in particular directional antennas like Yagi antennas or Quad antennas and how they determine the direction or signals.

Basic magnetic loop antenna examples and loop aerials theory explained. This article inclued some interesting tricks on building magnetic loop antennas and an usefull excell sheet to help compute magneti loop antennas calculating power efficiency from 10 to 40 meters band

Basically, this antenna is a 23-foot wire fed through a 4:1 un-un transformer. This antenna can be easily used in portable operation, for operating all bands from 40-10 meters.

A basic YAGI UDA online antenna calculator, accept as input frequency, number of elements, diameter of parasitic element and boom diameter. This online calculator will generate a basic design data including each element length and spacing.