Search results

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.

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.

This article demonstrate how to build and mount a 40 meter loaded dipole using basic materials. This antenna reduce the overall length of an HF dipole through the use of loading coils.

Learn how to build a simple 12vdc azimuth and elevation motor unit for the Arrow Satellite Antenna to improve your FM satellite communication experience. This DIY project involves using a camera tripod and basic materials like aluminum tube and standoffs. Get detailed instructions, including the gearhead motor product number for optimal performance. Discover where to purchase the necessary components and stay updated on alternative motor options. Enhance your ham radio operations with this homemade rotator setup, designed for easy satellite tracking and communication. Share feedback and connect with other radio enthusiasts for more tips and ideas.

A light portable 2 element Delta beam antenna for 14 MHz. It is basically a two element delta loop wire antenna made for portable usage providing good directivity and a 4.2 dBd gain

Construction tips of a basic wire antenna, the half wave dipole. Inverted V dipoles and effects of inverted v on radiation pattern.

Microwaves101 provides an extensive repository of information covering fundamental principles of microwave design, targeting engineers and radio amateurs interested in the higher frequency spectrum. The site features a detailed _encyclopedia_ of microwave terms and concepts, alongside practical design considerations for various components and systems. It serves as a foundational reference for understanding RF propagation, transmission lines, and active/passive microwave circuits. The resource includes numerous calculators for impedance matching, filter design, and other critical RF parameters, facilitating hands-on project development. Discussions on **10 GHz** equipment and **24 GHz** projects highlight practical amateur radio applications, extending to operations up to 134 GHz. Content spans from basic theory to advanced topics like MMIC design and antenna characteristics, supporting both educational and practical endeavors in microwave technology.

The Narrabeen JOTA and JOTI camp facilitates global communication for Sydney North Region Scouts and Northern Sydney Girl Guides, utilizing amateur radio and internet technologies. Participants engage in two-way radio contacts, often on **HF** bands, to connect with other scouting and guiding groups worldwide, fostering international goodwill and technical skill development. The event integrates both traditional **ham radio** operations and modern internet-based communication methods, providing a diverse experience for youth members. The resource outlines the specific activities undertaken at the Narrabeen site, including station setup, operating procedures, and the use of digital modes for JOTI. It highlights the educational aspects of the event, such as learning about radio propagation, antenna theory, and basic electronics, all within a structured camp environment. The page also provides logistical information relevant to the Australian context of the event.

Constructing a directional antenna for VHF operations, particularly for 2-meter band contests or local communication, often involves balancing performance with ease of build. The Moxon rectangle, a compact two-element beam, offers a good front-to-back ratio and gain in a smaller footprint compared to a Yagi, making it suitable for portable or temporary setups where space is limited. This design typically uses a driven element and a single reflector, bent into a rectangular shape to achieve its unique radiation pattern. The article details the construction of a 2-meter Moxon antenna, specifically for 144 MHz, utilizing readily available materials like PVC pipe for the frame and copper wire for the elements. It outlines the dimensions for the driven element at 970mm and the reflector at 910mm, with a spacing of 140mm between them, and a 50mm gap at the element ends. The feedpoint is a direct 50-ohm connection, simplifying matching requirements. The project includes a parts list, a basic diagram illustrating the element layout and dimensions, and photographs of the completed antenna. The author notes the antenna's performance during a QRP contest, achieving contacts up to 100km with 5 watts, demonstrating its effectiveness for low-power VHF work.

Learn how to easily build a 10-meter vertical antenna, perfect for DX contacts on the amateur radio bands. This flowerpot or T2LT design is portable, efficient, and ideal for ham radio operators looking to improve their DX performance. With just a few basic tools and materials, you can construct this antenna for portable operations or as a home station setup. Discover how to set up the antenna, improve its performance by raising it higher, and start making contacts with stations around the world. Watch a step-by-step guide on YouTube for building and testing this DIY ham radio antenna.

The original HEXBEAM was developed by Mike Traffic, N1HXA, in the early nineties. It is true that an M over W configured yagi antenna that resembled a butterfly was earlier tried successfully. But the advanced electrical design, the characteristic nesting concept and central terminal post that enable the multi band functionality along with the basic hardware design were all developed by Mike Traffie.

A simple superheterodyne receiver (3.5–30 MHz) for amateur radio achieves stable SSB-CW reception using modern BJTs, an AD831 mixer, a 6-pole quartz filter, and Seiler oscillators. Designed with high IF (4.5 MHz), compact AM-FM variable capacitors, and modular resonant circuits, it ensures selectivity, image rejection, and stable tuning. Built in a copper-lined wooden case, it features practical assembly techniques but lacks advanced features like AGC or S-meter. Effective on basic antennas, it achieves global reception.

Discover the key facts about what radio propagation is, the different types available and how they affect different frequencies.

Antenna most often used by Hams around the world. Inexpensive, effective and easy to build, what more could anyone ask for in a home made antenna.

Explains the fundamental purpose of a repeater, detailing how these automated relay stations overcome distance and terrain limitations for VHF/UHF communications. It traces the historical development from early Bell Telephone Labs "relay" stations in 1922 to Art Gentry, W6MEP's, pioneering K6MYK amateur radio repeater in the mid-1950s, which remains active today. The resource clarifies the distinction between simplex and duplex operation, including the unique function of a "parrot repeater" for single-frequency recording and playback. Delving into the internal workings, the guide breaks down a repeater into its core components: the antenna system, feedline (often _Heliax_ or hardline for minimal loss), duplexer, receiver, transmitter, and controller. It emphasizes the critical role of the duplexer in preventing receiver desensitization by isolating transmit and receive signals, even with distinct frequencies. The discussion highlights the importance of high-performance, durable antennas and low-loss feedlines, citing examples of equipment installed in the 1960s and 1970s that are still in perfect working order. Operating a repeater is also covered, with an explanation of frequency offset (e.g., the 600 kHz standard for 2 meters) and the function of _CTCSS_ (PL tone) for access. It outlines standard input/output offsets for various bands, from 6 meters to 23 centimeters, while noting regional variations. The guide also touches on features like autopatch and Digital Voice Recorders (DVRs), providing a solid foundation for understanding repeater technology and usage.

A Trapped dipole inverted V antenna for lower HF Bands. Construction details are for temporary installation. Permanent installations will require additional ruggedising and waterproofing however the basic electronics concepts remain the same. This project includes SWR plots for the three bands and pictures details of the homemade traps.

A rotatable 40-meter dipole antenna designed and constructed to fit within backyard constraints. The project utilized two fishing poles attached to a fiberglass center pole, resulting in an easy-to-build, lightweight, and cost-effective antenna. Essential materials included fishing rods, a center support pole, mast support, and basic tools. Linear loading was implemented to achieve the necessary length for optimal performance. The antenna, which proved effective during the contest, is ideal for field days and additional contest bands. Assembly and installation were straightforward, showcasing the antenna's practicality and efficiency.

This article on basic antenna theory explains why is a 5/8 wavelength vertical antenna better than a 1/4 wavelength antenna

Online antenna calculator for a basic 3 elements yagi uda directional antenna. The described antenna design offers a front-to-back ratio of at least 20 dB, a gain exceeding 7.3 dBi, and a bandwidth (SWR < 2) of approximately 7% around the center frequency. It has an input impedance of 50 ohms when using a straight split dipole, which can be substituted with a folded dipole of the same length, increasing the impedance to 200 ohms. A matching balun is required for coaxial feeder connection, and the boom should be made of a dielectric material, like wood.

Constructing a 5-element quad antenna, the author aimed for low cost and simplicity, resulting in an effective design with 11 dBi gain and SWR of 2:1 or better across the 2-meter band. Using wood and dowels, the antenna costs under $8 and takes less than two hours to build with basic tools. The model predicts excellent performance, confirmed by ARRL Lab measurements. Practical field results demonstrate improved communication, even in simplex mode.

This is basic instructions for homemade 4G Antenna working on 2600 MHz UMTS featuring 13 14 dBi gain. This antenna is desigend to resonate on microwave frequencies in two segments from 2500 to 2570 MHz for Uplink, and from 2620 to 2690 MHz for Downlink.

A 13-foot total radiating element length is achieved by combining a Buddipole Long Telescopic Whip with 4 feet of modified tripod tubes, forming a low-profile, multiband antenna for **POTA** operations. The resource details the transformation of an Amazon Basics Aluminum Light Photography Tripod Stand, focusing on electrically isolating the top two radiating sections from the bottom support. John, VA3KOT, outlines component sourcing, including the 9-foot 4-inch fully extended whip, and emphasizes using adhesive copper tape for reliable electrical contact and conductive grease to prevent oxidation at tube connections. The construction process, while not requiring specialized tools, highlights careful assembly to ensure proper electrical conductivity and mechanical stability. The author's experience with this setup suggests its effectiveness for portable activations, offering a discreet profile compared to larger antenna systems. The design prioritizes ease of deployment and transport, making it a practical solution for operators seeking a compact yet versatile antenna for field use.

This project outlines the construction of a simple TEFV (Tilted End-Fed Vertical) antenna suitable for backyard or park installations. The design requires basic materials such as 100 feet of coated stranded copper wire, wood stakes, metal ground rods, a non-conductive fiberglass pole, and essential tools like wire cutters and a soldering iron. The antenna is supported by a 20-33 feet tall pole and includes a 9:1 unun for impedance matching and a resistor for tuning. Step-by-step instructions guide the assembly, from preparing the wire and pole to connecting the unun and resistor, ensuring a functional and durable setup for outdoor use.

Antennas for low-power operation resemble those for 100W use. Minor adjustments, like capacitor voltage ratings, may apply, but basic principles persist. Portable antennas, notably Backpack Antennas for weight-conscious setups, hold relevance beyond QRP. While some antennas function acceptably at higher power, efficiency issues arise at QRP levels. Testing antennas at 100W exposes weaknesses, particularly in tuners, crucial for efficient QRP operation.

This article help on explaining what you need to start with amateur radio. By using a local ham radio club station to purchasing second hand radio equipment and how to get help on installing antennas.

The most basic form of repeater receives communication on one frequency and re-transmits it on a different frequency, a process known as duplex communication. This capability significantly extends the range of handheld and mobile radios, as repeaters are typically situated at elevated locations with high-gain antennas and greater transmit power. Repeaters commonly operate with FM modulation on the VHF (30 MHz – 300 MHz) and UHF (300 MHz – 3 GHz) amateur bands, which are ideal for portable and mobile devices. Access to repeaters is often controlled by a CTCSS or PL tone, an inaudible signal that prevents the repeater from retransmitting background noise. This mechanism ensures efficient use of the frequency and prevents illegal continuous transmission. Canadian regulations, for instance, require an Advanced amateur radio license and an available frequency within the band to set up a repeater, each assigned a unique call sign and transmit frequency. Configuring a radio for repeater use involves knowing the repeater's transmit frequency, its receive frequency offset (e.g., -600 KHz for VHF or +5 MHz for UHF), and the necessary CTCSS tone. The article references resources like Repeater Book for locating repeaters and provides practical examples for initiating and concluding a basic repeater session, emphasizing clear identification and concise communication.

The Aziloop DF-72 antenna system provides 72 K9AY headings and 36 loop axes, allowing for rapid switching in 60 ms. It integrates a switchable 18 dB preamp, a 4-step attenuator (0-18 dB), and four 7-pole preselection filters to optimize receiver performance. The K9AY load is adjustable from 250 Ohm to 950 Ohm in 50 Ohm increments, offering flexibility for various receiving conditions. Control is managed via an intuitive Windows UI, supporting Local, Client, or Server modes, with headless remote operation possible through the built-in Ethernet Server. _Omni-Rig_ support facilitates auto-filter selection, PTT muting, and Rig-Sync functionality, enhancing integration with existing station setups. Designed by _GW4GTE_, the system utilizes a low visual impact, small-footprint antenna with orthogonal loops and an earth connection. It is suitable for general monitoring, co-channel station resolution, basic direction finding, and interference reduction across the VLF to HF spectrum.

This page provides information and links about Quadrifilar Helix Antennas, the best antenna for APT satellite reception. It explains the basic design and configuration of QHA, including the research and developments that have been made over the years. The page offers insights into the radiation patterns and benefits of using QHA for APT ground stations, with examples of polar diagrams. If you are interested in learning more about QHA and its applications, this page is a valuable resource.

This page provides basic information about SWR (Standing Wave Ratio) and its importance for ham radio operators. It explains what SWR is, how to measure it, and why it is crucial to have a good SWR reading. The content covers the impact of SWR on antenna efficiency, power transmission, and potential interference issues. It clarifies common misconceptions like the impact of coax length on SWR. Suitable for hams looking to optimize their radio setup and avoid performance issues due to SWR issues.

A 5/8-wavelength vertical antenna for 2-meter FM operation is detailed, focusing on eliminating loading coils by utilizing a series inductor to cancel capacitive reactance at the feed point, thereby presenting a 50-ohm impedance match. The design illustrates three basic configurations, including a method employing a short-circuited coaxial stub for inductance, as implemented by K4LPQ. An alternative design is presented where the center conductor of the stub is extended one-quarter wavelength, creating a signal-frequency short and allowing for an insulated wire stub to develop the required series inductance. The article provides electrical theory and mechanical considerations for building the antenna, emphasizing the adjustment of stub length for proper impedance matching. This technical documentation is intended for amateur radio operators interested in homebrewing VHF antennas, offering practical insights into impedance matching techniques for vertical radiators.

"The QRP Adventures of VE3FI" is a captivating blog that chronicles the amateur radio experiences of Bill, VE3FI, over two decades. Holding Canadian Basic, 5-word CW, and Advanced licenses, Bill's main interests include DXing and QRP operations. The blog offers detailed accounts of his portable activations, such as a recent outing in March 2025, where he achieved impressive DX contacts on the 10-meter band using just 8 watts and a Hamstick antenna. Bill's engaging storytelling and practical insights make this blog a valuable resource for both seasoned and aspiring amateur radio enthusiasts.

DX web cluster that offers features for both registered and unregistered users. Unregistered users can view spots, filter by band and mode, search for callsigns, while registered users get all that plus the ability to submit spots, upload logs, see DXCC country status, antenna pointing info, real-time maps of spots, email alerts for DXCC countries on-air, and more. Basically, register for free to get the full DX cluster experience.