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A multiple page article about assembling the antenna system, this section includes informations on constructing of the concrete tower base, starting from setting up correctly the foundations in relation to the antenna height.

How to solve RFI problems caused by the charge controller, which is a PWM type charge controller, that generates a lot of EMI interference

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.

Operating on Airplane scattering. Scattering of radio signals by airplanes. An introduction to operating ariplane scattering, using aircraft to redirect RF that would otherwise be lost in space. Antenna Pointing, Doppler Shift/Digital Modes, using digital modes to operate airscatter.

When experimenting with the WellGood Loop antenna, I came across the PA0RDT MiniWhip design referenced in several places. The construction of the PA0RDT MiniWhip is simpler than the WellGood Loop since there are no inductors to wind, but during my testing, I have found the loop to have slightly better performance.

Collection of several topics on antenna tuners and their performance. Why use an antenna tuner? How does an antenna tuner…tune Does an antenna tuner fool the radio? Will an antenna tuner waste power? Can an antenna tuner help get more power to the antenna?

Design and manufacture antennas for mobile devices, wireless data including WiMAX, WiFi, and WISP (Wireless Internet), two-way radio and RFID (Radio Frequency Identification).

F5NPV introduces a variant of the W8JK antenna design, employing the MOXON principle. With extended monopoles, it outperforms the Open-Folded W8JK, yielding a 1dbd gain improvement, enhanced performance on 30m and 10m bands, bi-directionality, and lower side attenuation. The design's focus on higher radiation impedance results in increased antenna efficiency and reduced losses. Despite these improvements, the bill of materials remains unchanged.

Installation and modification of the popular Butternut HF9V antenna with the optional 160 meter addon. Article includes a modification to improve the performance on the top band

This 10 meter antenna is right out of the ARRL Antenna Book. There are 5 elements on a 24 feet boom and it performs well from 28.0 to 28.9 MHz.

A document that will guide you on Coaxial-Cable trap optimization process to gain on global antenna performance and on increasing effective bandwidth.

If You are using a separate receive antennas then you need a good protection circuit to eliminate the possibility of blowing out the receiver front-end while using these auxiliary receive antennas specially on low bands.

Get the most out of your station with K6TU.NET professional grade propagation prediction, and model your antenna performance over actual terrain using high resolution elevation data

The Linked Dipole is a multiband antenna designed for 80/60/40/30/20m bands, optimized for the (tr)uSDX low bands configuration. It incorporates a 1:1 Balun to prevent common mode currents, ensuring balanced operation with coaxial cable. The Balun, wound on an FT140-43 core, achieves 37-40dB attenuation. The design includes a 3D-printable housing for compactness and waterproofing, with labeled link insulators for ease of use. Wire lengths were meticulously adjusted for optimal performance with a 7m pole and 3m rope extension, ensuring the antenna's ends are off the ground for improved behavior. The project includes downloadable printables for DIY construction.

This active antenna for the shortwave band provides surprising performance, even indoors. As the name implies, the main loop is made from a Hula-Hoop with the metallic paint stripped off and a single turn of 14AWG copper wire inserted inside the hoop.

A 3 band dipole antenna for 40-80-160 meter bands, It's made with easily available materials and is designed for inverted V mounting. The antenna is shortened for these bands, but still manages to make contacts in 80m and 160m with stations in Canada and the USA. The construction details are provided, including the dimensions of the antenna elements and the traps. The antenna is easy to build and provides good performance in all three bands. In Italian.

TelExpress provides a wide array of RF and data connectivity products, including various coaxial cables like LMR-series equivalents, fiber optic cables, and Ethernet solutions. Their inventory supports diverse amateur radio and telecommunications requirements, from antenna feedlines to network infrastructure. The site emphasizes bulk cable availability and custom assembly services, catering to both individual hams and larger installations. Key offerings include _low-loss coax_ for HF and VHF/UHF applications, along with a comprehensive selection of RF connectors. They also supply patch panels, Ethernet cables (Cat5e/Cat6), and general wireless and telecom hardware. Customers can find components for building robust station infrastructure, ensuring signal integrity across various frequency bands. The platform facilitates procurement of essential parts for new builds or upgrades, supporting reliable RF system performance.

Ham radio activity and homebrew from Italy with some interesting article on QRSS, decoding interfaces, APRS and antennas

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

This antenna just requires about 24m of free space instead of 41m that a normal half wave 80m antenna needs to hang up. The so called loaded dipole uses a coil in every dipole arm to electrically lengthen the mechanical too short dipole arms. Every coil has an inductivity of 120 microHenry.

Experimental Long Boom Antennas - CP, LPDA, multiband with several NEC Files for 50MHz 144MHz 222 MHz 432MHz but also 902MHz and 1296 MHz Antenna projects. Includes also for each antenna model, in a general comparison table each antenna characteristics including Directive Gain, G/T, E-F/R, H-F/R abd Boom Length. This is a great value comparison table of several commercial and home made VHF UHF antenna projects.

HAM-made engineering products supplies and produces coaxial relays, antenna switches, sequencers, roller inductors, variable capacitors, low noise preamplifiers, RF power rotary switches and coil bodies.

PSK Reporter provides a real-time visualization of amateur radio digital mode reception reports, aggregating data from a global network of monitoring stations. This platform is particularly useful for operators utilizing modes such as FT8, FT4, and PSK, allowing them to observe signal propagation paths and assess their station's reach. The interactive maps display reception reports, enabling hams to analyze band conditions and optimize antenna performance for various frequencies and times of day, aiding in understanding ionospheric conditions. Operators can filter reports by callsign, band, mode, and time, gaining insights into specific propagation events or evaluating the effectiveness of their transmit setup. The data collected helps in predicting optimal operating windows for DX contacts across various digital modes. Philip Gladstone is the contact person for comments and discussions regarding the system.

The "DIY Telescopic-V Antenna £35" project showcases the creation of a budget-friendly, portable telescopic V-shaped antenna inspired by commercial designs. Using eBay-sourced telescopic whips and custom mounting solutions, the author documents their process, testing, and adaptations. Despite challenges like weather and missing tools, the antenna performed well across multiple bands, enabling successful QSOs. Future improvements include exploring loading coils and testing in better locations. The compact design offers versatility for amateur radio enthusiasts seeking an affordable and practical solution.

Results or performance test using an harpin antenna for the 7 MHz

Pro-cell Co., Ltd was established in 1995 to produce and develop wireless components. In the beginning stage, we concentrated on producing GSM antennas, now produce Commercial- RFID, GSM UMTS GPRS LTE WLAN Wi-Fi Wi-Max, PMR & Tetra antennas

Wuxi Venus Information Technology is an amateur radio devices dealer in China, source for high end, high performance RF products,Control products,APRS products and Commercial products. It provides a variety of solutions to the antennas systems, APRS,electronics kits and electronics components

This PDF document provides a detailed guide on designing an 80m loop antenna. The content covers the construction, setup, and tuning of the loop antenna, offering practical tips and considerations for optimal performance. Whether you are a beginner looking to enhance your radio communication capabilities or an experienced operator seeking to improve your antenna system, this resource serves as a valuable reference for building an effective 80m loop antenna.

What is antenna polarization, and why does it matter. Horizontal versus Vertical versus Circular polarization. Undestanding how antennas perform better with different polarizations.

Antenna for Field Day or Everyday. aA simple yet rugged six band quarter wave vertical antenna system perfect for field day or home use.

LB3HC's hightech blog - Amateur radio, RF design, electronics, uC, software, Arduino, AVR, Antennas

Operating an amateur radio station effectively requires reliable coaxial cable to minimize signal loss between the transceiver and antenna. SIVA Cavi, an Italian manufacturer, produces a range of coaxial cables, including specific 50 Ohm low-loss types suitable for amateur radio applications. Their product line features cables like **RG 58 SHF1**, **RG 213 SHF1**, and **RF 400 SHF1**, which are commonly deployed in HF and VHF/UHF setups. The company also offers specialized cables such as the **HF 214 UF Ultraflex**, a high-performance broadband low-loss 50 Ohm cable designed for flexibility and reduced attenuation across various amateur bands. These cables are engineered with solid or foam dielectric materials, impacting their electrical characteristics and suitability for different power levels and frequency ranges. For instance, foam dielectric cables often exhibit lower loss at higher frequencies, a critical factor for VHF/UHF operations. Beyond amateur radio, SIVA Cavi manufactures cables for digital video broadcast, offshore marine use, and fire detecting systems, demonstrating a broad engineering capability in coaxial cable technology.

The PAC-12 Antenna, a multi-band portable vertical, is meticulously detailed in this construction article by James Bennett, _KA5DVS_. The design emphasizes ease of homebrewing using readily available components from local hardware stores, including replaceable loading coils. It outlines the preparation of the 72-inch telescoping whip (originally from Radio Shack, with an alternate source now provided by _Pacific Antenna_), the construction of the loading coils from PVC risers, and the fabrication of the aluminum rod base sections. Specific instructions cover threading aluminum rod with a _1/4-20 threading die_ and assembling the feedpoint insulator with a BNC connector, along with recommendations for radial deployment. KA5DVS, an avid traveler and QRP enthusiast, developed the PAC-12 to address the bulkiness of random wire setups and the limitations of commercial portable antennas like the Outbacker or SuperAntennas MP1. His goal was a lightweight, packable antenna that disassembles into 12-inch sections, achieving an assembled length of approximately 8 feet. The design strategically places the loading coil away from the base for improved efficiency. The PAC-12 notably placed first in efficiency compared to a quarter-wavelength wire vertical at the HFPack antenna shootout during the Pacificon conference in October 2001, demonstrating its practical performance for field operations. Appendix C showcases various _NJQRP Club_ members' PAC-12 constructions, including a 20m beam made with multiple PAC-12 elements.

This article details the design and construction of a homebrew two-element loop antenna array for HF reception. The DIY receiving antenna system consists of two 30-inch diamond-shaped loops spaced 20 feet apart, offering superior directivity compared to traditional vertical arrays. The design features broadband operation from 160m to 20m bands, requiring only phase-delay adjustments via feedline lengths. This home-built antenna system achieves 9dB RDF (Receiving Directivity Factor) performance comparable to a 300-foot Beverage antenna, while requiring minimal space and no ground radials, making it ideal for suburban installations and low-band reception.

The Bazooka antenna, a coaxial dipole, functions as an omnidirectional antenna with vertical or horizontal polarization. Patented in 1939 and refined in 2006, it features a quarter-wavelength coaxial cable with separated conductors. The outer conductor connects to a sleeve, while the inner conductor extends vertically. Initially complex, it has been simplified for versatile use, including military applications. Adding elements can modify its behavior for NVIS or Yagi-Uda configurations. Experiments in 2007 at the Campus de Pesquisas Geofísicas in Paula Freitas-PR demonstrated consistent VHF and UHF performance, showing reliable return loss measurements despite variable weather.

Mounting on roof at the right ground level can greately impact on antenna performances because will affect the radiated angle of energy.

This article describes a simple yet effective multi-band vertical HF antenna design that performs exceptionally well across 80m to 10m bands. The antenna consists of a 13.4m wire mounted on a 12.4m Spiderpole, complemented by four 12m radials and a ground rod. Initially tuned with a manual LC circuit, it was later upgraded with a CG3000 remote auto ATU for convenient band switching. Despite antenna modeling software suggesting limited performance on higher frequencies, the system demonstrated excellent DX capabilities across all bands, outperforming more complex vertical antenna designs.

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.

This PDF document reviews the POTA PERformer Antenna by KJ6ER, providing insights and details about its performance and features. The content is aimed at hams looking for information on this specific antenna model to help them make an informed purchasing decision. It contains technical specifications, user experiences, and possibly recommendations for optimal use. The review is valuable for hams interested in portable operation and seeking a reliable antenna solution for Parks on the Air (POTA) activations.

A dual band 40-80 vertical antenna on an 18m Spiderbeam Fiberglass Spiderpole, with monoband performance

The CobWebb antenna project is a compact, multiband HF solution ideal for amateur radio operators. Covering 14-28 MHz, it features a square dipole array with near-omnidirectional coverage and unity gain. This guide details a DIY approach, using a 1:4 current balun for impedance matching. Construction involves aluminum and fiberglass tubing, with optimized element tuning for SWR performance. Weather resistance improvements and resonance shift considerations are also discussed. Build your own CobWebb antenna for an efficient, space-saving HF experience.

This page offers an online antenna designer tool for Hams to calculate the dimensions needed to construct a coaxial collinear antenna for a specific frequency. It provides guidance on the required frequency input, coax velocity factor, and element measurements for optimal performance. The tool is recommended for experienced antenna builders due to its complexity and technical requirements. Users can input the frequency in MHz and the tool will generate the necessary dimensions based on the chosen parameters. The page emphasizes the importance of accurate measurements and connections for successful antenna construction.

This article documents the author's journey in building, modifying, and testing a DIY short vertical antenna for 40, 30, and 20 meters, with potential 80m capability. Initially inspired by Parks On The Air (POTA), the author explores pedestrian mobile operation and details various experiments to enhance antenna performance. The piece highlights challenges, SWR tuning, portability, and practical results, emphasizing a balance between efficiency and size. Ultimately, it showcases the adaptability of DIY antennas for portable ham radio applications.

In the quest for an ideal field portable antenna, the author recounts experiments involving various wire configurations. While a previous candidate, a 41ft random wire, proved effective but lacked stealth, the search led to a surprising rediscovery of a design previously rejected—the Rybakov Antenna. With a focus on simplicity, rapid deployment, and multiband capability, the author explores the versatility of a 26ft Rybakov, avoiding the halfwave trap. The article delves into the antenna's performance and its potential as a discreet, resonant solution for field operations, addressing the challenges encountered during a POTA activation. Additionally, the Unun/Balun design used in conjunction with the Rybakov Antenna is discussed, providing insights into achieving a balanced system.

A dual band X-frame wire antenna made using 4 turns for response down to 3 MHz or so, and 2 turns (switched) for response up to around 18 MHz. The loop configurations are tuned using common eBay 365 pF tuning caps.

Operating within the low-frequency spectrum, transformers serve critical roles in antenna systems, particularly for 160m applications. The resource details the construction and performance of 1:1 transformers built on BN-73-202 cores, emphasizing their use as hybrid combiners or phase inverters for RX antenna arrays. Measurements reveal that these transformers exhibit minimal losses, around 0.12 dB at 1.8 MHz, with variations based on wire type and number of turns. The analysis includes comparative data on transformer performance, highlighting the impact of different winding techniques on frequency response. Notably, the use of coaxial cable for winding improves bandwidth while maintaining low-frequency efficiency. The resource also discusses braid breaker transformers, which minimize inter-winding capacitance, achieving low losses around 0.21 dB at 1.8 MHz. These insights are crucial for optimizing low-band antenna systems, allowing operators to make informed decisions regarding transformer design and implementation.

The _G3TSO_ Mobile Antenna Page details construction and tuning methods for mobile antennas operating across **10 to 160 metres**. The content describes a Hustler-based design, optimized for RF performance and vehicle speeds, featuring centre loading. For optimal operation on various bands, the loading coil placement requires clearance from the vehicle body. Antenna resonance is critical for efficient mobile operation. A mobile antenna's base impedance may be as low as 27 ohms, requiring specific matching to achieve maximum radiation, as a minimum SWR at the transmitter does not always indicate resonance or maximum output. Tuning involves physical adjustment of antenna length to achieve resonance at the operating frequency. The _G3TSO_ page outlines a tuning procedure utilizing a low-power signal source and a field strength meter to identify maximum radiation before impedance matching. Loading coil placement, either at the base, center, or top of the antenna, influences radiation efficiency and mechanical stability for mobile installations. Centre-loaded whips, such as the Hustler design, offer a compromise between efficiency and stability, often for single-band operation. Helically wound antennas, including those for **28 MHz**, may present base impedances around 17 ohms, resulting in a 3:1 SWR at resonance. Low resistance grounding at the antenna base is also specified for optimizing performance and minimizing RFI during mobile operation. DXZone Focus: Mobile | Any | Antenna Tuning | HF

In this article, Steve G0UIH presents a straightforward guide for constructing a lightweight 15m 3 Element Yagi antenna with impressive performance metrics. With a focus on ease of construction and efficiency, the design boasts a nearly 8.2dbi forward gain and 30db front to back ratio. Utilizing readily available materials and a hairpin match for impedance matching, this Yagi offers broad bandwidth and simple tuning for optimal operation across the 15m band.

Originally designed by John Kraus, W8JK in about 1940, this antenna has some interesting properties. The W8JK antenna is 2 (Two) centre-fed double-dipole fed by a pair of anti-phase signals. Small size, simple antenna, offer nice performance but need a tuner. Tested in this project from 30m to 6m bands

There are quite a few recipes for building a suitable transformer for an end fed half wave antenna (EFHW), but I was never sure I really understood the main principles. So, I wound a bunch of transformers, made measurements on them using my NanoVNA, learned how to get what I really wanted out of the VNA measurements, and in the process discovered how to build better transformers and be able to predict what they will do