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This Antenna is not really practical for AO-40 reception, but horn antennas have a number of qualities useful in microwave antenna testing and noise figure measurements.

Testing and comparison of traps and trap antennas

Posts about bazooka antennas at towertalk mailing list

Demonstrates the product line of _LZ Antenna Ltd._, a Bulgarian manufacturer specializing in amateur radio antennas and custom electronic devices. The company focuses on robust, high-quality HF multiband Yagi and vertical antennas, leveraging over 20 years of experience from founder Georgi Georgiev in radio amateur development. Featured models include the LZA 8-4, LZA-10-3, and the LZA-7-3A WRTC 2022, alongside various rotary dipoles like the LZA1 40/30m. Provides specifications for several Yagi antennas, such as the LZA-9-5, LZA-13-7, and LZA-6-3 (a 6-element, 3-band design). The company emphasizes applying "leading edge technology" to high-frequency communication equipment production, with products designed for durability and performance. The LZA-10-5 Yagi offers **12.5 dBi** gain on 10m, while the LZA-13-7 provides **13.2 dBi** on 20m, showcasing competitive gain figures for DXing and contesting.

The document provides a comprehensive overview of baluns, which are devices used to connect balanced loads, like dipole antennas, to unbalanced inputs, such as coaxial cables. It covers various types of baluns, including voltage and current baluns, and their design, construction, and testing. The text discusses the importance of baluns in preventing RF currents on coax shields and their applications in Ham radio setups. It also includes practical advice on selecting and using baluns based on antenna impedance and power ratings, along with detailed performance evaluations and construction tips for different balun configurations.

An interesting article about planning and testing beverage antennas for 80 and 160 meters in a rural location

Testing log wire antennas and a unun by G0KYA

Contesting, CW, antennas and review on TK/OE5XVL DXpedition 1999 plus my GD/OE5OHO DXpedition in 1997.

Ham radio Blog, focusing on homebrewing and testing antennas, rig mods and contesting.

On this page you will find information about previous, current and future operations of our contest team, different articles, links and info about contesting, DXing, contests calendar, propagation, antennas, equipment, awards, and much more.

This book provides plenty of insight into how you, too, can Capture the Magic of Six Meters. It covers propagation, equipment, software, antennas, awards and contesting, as well as assistance in finding the magic.

This project details the construction and testing of a M0PLK Delta Loop antenna for the 20-10m ham radio bands. Inspired by positive reviews highlighting its reduced local QRM compared to Cobweb antennas, the author built the antenna using aluminum tubes, DX-Wire FS2 wire, and a 1:4 balun. A mix of custom 3D-printed parts and careful assembly ensured stability and performance. Initial VSWR measurements met expectations, and test QSOs demonstrated success across multiple bands. Future enhancements include adding a lightweight, remote-controlled rotator for directional capabilities.

A portable operation experience with a SpiderBeam pole during a contest, testing wire antennas, like dipole and delta loops configurations on 20 40 and 80 meters band.

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.

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.

This innovative antenna tuning unit (ATU) enables QRP operators to match their antennas without transmitting RF signals. Using a noise bridge technique instead of traditional transmit-and-tune methods, it achieves truly silent operation. The design incorporates an L-match network with switched inductors and variable capacitor, handling impedance matching from 3-30MHz. Operating from a 9V battery, it includes a built-in RF power meter and dummy load for QRP transmitter testing. The compact unit is particularly suitable for portable operations where minimal RF emissions during tuning are desired.

This project focuses on testing and comparing various antennas for receiving ADS-B (Automatic Dependent Surveillance-Broadcast) signals, utilizing software tools like RTL1090 and Virtual Radar with an RTL-SDR dongle. The goal is to evaluate the reception range ("ReceiverRange") and performance of different antenna types when tracking aircraft signals, particularly around the Amersfoort area. The project includes a comprehensive photo album documenting the antenna designs and setup processes, serving as a valuable resource for enthusiasts building ADS-B reception systems

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.

Designing and Testing a PCB Wideband Spiral Antenna. The 800 MHz+ and 300 MHz+ spiral antennas by Hexandflex

This article details the author's process of designing and building a trap dipole antenna for the 17, 12, and 6-meter amateur radio bands using a Yaesu FT-450 transceiver. The antenna incorporates parallel-tuned circuit traps to enable operation across multiple bands without switching aerials. Key construction details, including coil and capacitor specifications, are discussed, along with the testing results, which include successful long-distance communications on the 50 MHz band. The article highlights the flexibility of home-built antennas and provides insights for amateur radio enthusiasts looking to optimize multi-band performance.

Discover the secrets of Six Meters with this comprehensive eBook by Jim Wilson, K5ND. Learn about the magic of 6-meter DXing, including propagation, antennas, equipment, operating software, and more. Whether you're a beginner or an experienced ham radio operator, this book covers everything you need to know. With over 8,000 downloads, this updated version includes new chapters on FT8/FT4, MSK144, and Q65 modes, as well as contesting, rover operation, and awards. Get your hands on this valuable resource and enhance your 6-meter DXing experience today.

In his POTA activation, WK4DS experimented with radials for hamstick antennas. Despite sun and RF noise challenges, successful connections were made. Surprisingly, tuned radials proved unnecessary, simplifying setup. Hamsticks demonstrated versatility across frequencies. Increased power improved signal quality, sparking his curiosity for further exploration in radio technology.

Testing of real antennas is fundamental to antenna theory. The most common and desired measurements are the antenna radiation pattern including antenna gain and efficiency, the impedance or VSWR, the bandwidth, and the polarization. The procedures and equipment used in antenna measurements are described in this page.

Chavdar Levkov, LZ1AQ, presents an experimental comparison of small wideband magnetic loops, building on his previous work on wideband active small magnetic loop antennas. His research focuses on increasing loop sensitivity by maximizing the short-circuit current, which is directly tied to the "loop factor" M = A/L, where A is the equivalent loop area and L is its inductance. Levkov's methodology involves reducing inductance and increasing area through parallel or coplanar crossed (CC) configurations, comparing these designs against a reference single quad loop of 1 m2 area. Experimental verification included testing three distinct loop types: a simple quad loop, two coplanar crossed (CC) loops, and eight parallel loops, all designed to have a total geometric area of 1 m2. Measurements were conducted at 1.8, 3.5, 7, and 10 MHz using a small transmitter 270 meters away, with a Perseus direct sampling receiver for precise signal level assessment. The results consistently showed that CC loops, particularly Loop 5 (two CC circular loops with 1.44 m2 total area), yielded significantly higher currents, up to 9.1 dB over the reference loop at 3.5 MHz, validating M as a reliable predictor of loop sensitivity. Numerical simulations using MMANA further corroborated the experimental findings, demonstrating an almost perfect correlation between the calculated M factor and the induced loop current for 15 different loop models. Levkov concludes that CC loops offer superior sensitivity for a given loop area, while parallel loops are advantageous for minimizing physical volume. Practical recommendations suggest using loops with an M factor greater than 0.5 uA/pT for quiet rural environments, and he provides a spreadsheet tool, WLoop_calc.xls, to aid in optimizing loop configurations for specific operational needs.

Spectrum Communications specializes in a range of communication products, including antennas and cables for HF, VHF, and UHF (RX & TX), CB radio boards, electronic components, RX & TX boxed products, PCB products, and general accessories for testing and alignment.

The author struggled with receiving antennas on his property. After a standard Beverage on Ground (BOG) antenna failed, he built a Reverse Beverage on Ground (RBOG) using telephone cable. He details construction and testing, finding the RBOG outperformed other antennas in noise level, signal strength, and reception pattern. Software modeling helped optimize the antenna length. Unfortunately, the project ended when telephone cable from the second RBOG was stolen.

The Kenwood TS-440S operates across HF bands with a frequency range of 10 MHz to 30 MHz, featuring SSB, CW, and FM modes. It supports various modifications for improved performance, including circuit enhancements and software updates. Users can access detailed diagrams and troubleshooting guides to optimize their setup. The transceiver's architecture allows for easy integration with external devices, enhancing its versatility in the field. Practical applications include participation in DXing and contesting, where the TS-440S's capabilities can be fully utilized. Operators have reported significant improvements in signal clarity and reception after implementing recommended mods. Comparisons with other HF transceivers highlight the TS-440S's reliability and adaptability, making it a preferred choice among seasoned operators. Resources for power supplies, antennas, and additional accessories are also available, ensuring a comprehensive support system for users aiming to maximize their station's potential.

This blog chronicles over a decade of portable HF contesting from rural Ireland (2008–2019) by Olivier, operating under callsigns EI/ON4EI, EI8GQB, EI1A, and EI7T. Using only green energy from a caravan, he achieved top-tier results in major international contests—including 1st World in the 2018 IARU HF Championship (SSB LP) and multiple 1st-place finishes in CQ WW and CQ WPX SSB Europe. Operating in the demanding Single Operator All Band Low Power and SO2R categories, he deployed up to five antennas across five bands, often in remote or emergency-style conditions. The narrative blends technical detail, fieldcraft, and personal reflection, documenting triumphs, setbacks (including carbon monoxide poisoning), and the logistical challenges of sustainable portable operation—culminating in his decision to transition to team-based contesting and future DXpeditions.