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The 160/80m coaxial receiving loop antennas are designed to enhance reception on the top bands while minimizing noise. These antennas are particularly beneficial for operators with limited space, as they can be constructed using lightweight materials, making them portable and easy to deploy. The standalone 80m loop has a diameter of approximately four feet, allowing for easy rotation and installation above existing VHF antennas. Over the years, many amateur radio operators have turned to loop antennas as a viable alternative to traditional beverage antennas. The design allows for significant noise reduction, especially when paired with a quality pre-amplifier. Experimentation with various configurations has led to the discovery that diamond-shaped loops provide optimal performance. Users have reported a noticeable improvement in signal quality, making these loops a valuable addition to any low-band DXing setup.

Base station and repeater antennas, mobile antennas, ,multi-band HF antennas , handheld transceivers, receiving and scanner antennas, power meters, swr meters, power supplies, coaxial switches

K9AY loop antenna installed at PA6Z Contest group. This is a receiving antennas for the low bands (160m, 80m and 40m). Include schematics and info on a building the control box, preamplifier and low-pass filter

WiNRADiO Communications, a division of Radixon Group, was established in 1996 to commercialize extensive research in radio communications. The company specializes in integrating radio and computing technologies, offering a diverse product range for government, military, security, and amateur radio enthusiasts. Their product line includes the WR-G65DDCe 'EXCALIBUR Sigma' HF/VHF SDR receiver, noted for its capabilities, and the G31DDC EXCALIBUR, recognized for its price/performance ratio in shortwave listening with improved AMS and Noise Blanker features. The company also produces the G39DDC series EXCELSIOR for serious monitoring, WR-G526e/G527e/G528e modular SDR solutions for high-performance applications like phase-coherent direction finding, and the low-cost WR-G305e/G305i VHF/UHF receivers. Professional counterparts, the WR-G315e/G315i, support APCO P25 decoders and trunking options. WiNRADiO's offerings extend to the PFSL-G3 field strength logging system for mobile signal coverage, advanced multichannel telemetry systems like the MS-8323, and specialized antennas such as the AX-31C Log-Periodic and AX-81S active HF antenna. DRM decoder software is available for G3 Series receivers, enabling clear reception of DRM broadcasts. The WSS-420 Weather Satellite Receiving System and various antenna rotators are also part of their product ecosystem. WiNRADiO supports multiple operating systems, with MacRadio for Apple Macintosh users and LiNRADiO for Linux developers, providing drivers and network receiver solutions like the RLX-810.

Lyle Koehler's article on remote use of LF loop antennas for receiving purposes.

A 2-meter Turnstile antenna, detailed for amateur satellite communication, offers a straightforward build for those looking to engage with orbiting transponders. The author, WB8ERJ, shares his personal design and construction methods, emphasizing the antenna's simplicity and effectiveness for LEO (Low Earth Orbit) satellite work. This design provides a circularly polarized signal, crucial for mitigating _Faraday rotation_ and signal fading often encountered with linearly polarized antennas when tracking satellites. Construction involves readily available materials like PVC pipe and copper wire, making it an accessible project for many hams. The article includes practical advice on element spacing and feed point considerations, drawing from the author's hands-on experience in the shack and field. It highlights the antenna's utility for receiving signals from various amateur satellites, including the popular AO-91 and AO-92. The Turnstile's inherent omnidirectional pattern in the horizontal plane, combined with its circular polarization, yields consistent signal reception, often resulting in **stronger decodes** and **more reliable contacts** compared to basic dipoles or verticals.

Learn basic theory on antennas, and notes on homebrewing efficient shortwave antennas

There are lots of good designs for matching transformers for receiving antennas. Make it yourself it's cheap and easy, and very high performance. This is the design used in the TRX-9 transformers.

A ranking of receiving antennas based on noise being evenly distributed in all directions. These rankings are most accurate in the frequency range of AM broadcast, 160 or 80 meter bands

K9AY receiving antennas for PA6Z made by PA9M

Article on radiation patterns of small loops, equivalent circuits of loop antenna, small loops as receiving antennas, ferrite loops

This description is taken from the Pete's W2PM posting into Topband reflector.

Comparison chart for low-band receiving antennas

Transformers theory and calculator of turns on binocular cores. Comparison with toroid cores.

Comprehensive information page about bi-directional Beverages, including applications, construction details, and tips.

The TMB-1 is an RF amplifier unit / receiving accessory that can be used with a low-impedance broadband loop, a high-impedance terminated loop (such as a Pennant, Flag, or Kaz Delta), and whip (telescoping rod) antennas.

Receiving rhombic antenna experiments by Jelmer PA5R

Hi-Z Antennas offers specialized high-impedance receiving systems, primarily focusing on phased vertical arrays for HF reception. Their product line includes preamplifiers designed for shortened vertical antennas, featuring optimized 15dB gain and array-matched characteristics. These components are engineered to enhance weak signal reception and improve signal-to-noise ratio across the HF spectrum. The company provides controllers for managing multiple vertical elements in a phased array configuration, enabling directional reception patterns. These systems are particularly effective for mitigating local noise and interference, a common challenge in urban and suburban operating environments. Specific offerings include solutions for 160-meter and 80-meter bands, addressing the unique requirements of low-band DXing. Technical details often reference components like the 2N3866 transistor in preamp designs and discuss concepts such as out-of-band attenuation. The focus remains on optimizing receiving antenna performance through impedance matching and active amplification, rather than transmit capabilities.

Demonstrates a range of specialized radio frequency equipment and consulting services for amateur and professional applications. The offerings include _Vector-Finder_ direction finding antennas, various test equipment such as _gate dip meters_ and RF sniffers, and communications receiving adjuncts. Additionally, the company produces satellite antennas for weather satellite reception, voice amplification devices like the _Flex-Mike_, and custom prototype circuit boards. The company's product line addresses needs for precise RF measurement, signal detection, and specialized antenna systems, particularly for direction finding and satellite communications. Their historical association with National Radio (HRO) suggests a legacy in radio technology. The site also highlights a subsidiary, Sierra Mountain Products, which offers outdoor recreational gear, indicating a diversification beyond core RF manufacturing.

A reduced size of the popular K9AY receiving loop antenna

RF Systems develops and produces antennas and accessories for governmental and military organisations, shortwave and scanner listeners, radio amateurs, yachting circles and professional users of receiving and transmitting equipment.

Optimizing weak signal reception on the HF bands, particularly in the presence of strong local QRM, often necessitates specialized receiving antenna systems. This resource details the _HI-Z Antennas_ product line, focusing on phased vertical arrays designed for superior noise rejection and directivity. It covers components such as the 4-Square and 8-Element array controllers, which allow for rapid switching of receive patterns, and dedicated low-noise preamplifiers to improve system sensitivity. The site also presents various bandpass filters, crucial for mitigating out-of-band interference and enhancing the dynamic range of the receiver. The HI-Z systems are engineered to provide significant front-to-back and side rejection, often yielding **20-30 dB** of attenuation to unwanted signals, which is critical for DXing and contesting. Users can achieve a notable reduction in local noise, allowing for the discernment of signals that would otherwise be buried. The array controllers facilitate quick pattern changes, enabling operators to null out interference or peak weak signals from distant stations, effectively extending the reach of their receive capabilities by improving the signal-to-noise ratio.

A review of all possible receiving antennas for top band 160 meters

Amateur Television (ATV) operations involve transmitting and receiving live or recorded video and audio signals over amateur radio frequencies. Unlike narrow-band modes, ATV utilizes a wider bandwidth to convey video information, often requiring specialized transceivers, antennas, and signal processing equipment. This mode allows hams to share visual content, demonstrate projects, or conduct video conferences, typically on VHF, UHF, and microwave bands due to the bandwidth requirements. The SwissATV resource focuses on the technical aspects and community engagement surrounding ATV within Switzerland. It covers topics relevant to setting up ATV stations, understanding signal propagation at higher frequencies, and participating in local ATV activities. The site serves as a central point for Swiss ATV operators to exchange knowledge and coordinate transmissions, fostering the growth of this specialized amateur radio mode.

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.

Designing and constructing a two-element receiving loop antenna array for HF operation involves specific considerations for achieving high directivity and noise reduction. This resource details a homebrew system comprising two 30-inch diamond-shaped loops, spaced 20 feet apart, which are fed through mast-mounted preamplifiers and passive signal combiners. The operational principle relies on adjusting phase delays between elements via precise _Belden 8241_ coaxial cable lengths, optimized for specific bands from 160m to 20m. Performance data, derived from _EZ-NEC_ modeling, illustrates consistent 90° azimuth-plane beamwidth and low take-off angles across the target bands, with _Receiving Directivity Factor_ (RDF) values comparable to a 300-foot Beverage antenna. The article presents detailed elevation and azimuth plots for 20m, 30m, 40m, 80m, and 160m, demonstrating the array's ability to provide strong response at low DX angles while also supporting _NVIS_ signals. Key components like the _DX Engineering RPA-1_ preamplifier and _DXE RSC-2_ signal combiner are discussed, alongside the importance of impedance matching to preserve antenna patterns. The construction emphasizes self-contained elements that do not require ground radials, offering a compact solution suitable for suburban environments and stealth installations, with a focus on optimizing receive performance independently from transmit antennas.

The video delves into the fascinating science behind antennas, which are crucial for receiving and transmitting electromagnetic waves. It explains how antennas convert electric signals into electromagnetic waves for transmission, and how they operate through the oscillation of positive and negative charges in dipole arrangements. Practical antenna implementations, such as dipole antennas for TV reception and Yagi-Uda antennas with reflectors and directors, are also discussed alongside modern dish TV antennas with parabolic reflectors for signal processing. It's a comprehensive overview of how antennas work and their significance in communication technology.

Active Receiving Antennas, designed for reception of shortwave, mediumwave and longwave signals and VHF/UHF signals

Manufacturer of amplifier for small magnetic and electric receiving wideband antennas, and variable delay line kit for active antenna phased arrays

A Dutch website dedicated to weather satellite reception with many documents related to antennas, software and techniques on receiving signals from weather satellites.

Operating in a Single Operator Two Radios (SO2R) setup, especially with beverage antennas, often exposes the receiving radio's front-end to significant RF energy from the transmitting radio. This resource details a practical, homebrew receiver protection circuit designed to mitigate this risk. The core of the design involves a non-inductive 2W 22 Ohm carbon composition resistor in series with the RX antenna line, followed by two stacks of four fast-switching diodes (e.g., _1N914_) configured in opposite polarizations. This arrangement effectively clamps the incoming voltage to approximately 2.8 V peak-to-peak, safeguarding sensitive receiver input components. The series resistor plays a crucial role by absorbing excess power, preventing the diodes from exceeding their current ratings and potentially failing open, which would leave the receiver unprotected. The author, _N4KG_, measured up to 50 watts of coupled power between 80M slopers on the same tower, highlighting the necessity of such protection. The design is presented as a cost-effective solution to prevent damage to receiver input transformers, with the author noting successful protection of a receiver even after a resistor showed signs of overheating. This simple circuit can be integrated via a transverter plug, offering a robust defense against high RF input.

Analysis of flag receiving antennas using MININEC with focus on relation of size and atenna height by VE6WZ

Experimenting with capacitive antennas for 40 and 80 meters band. A very space-saving antenna with good receivings caracteristics

An article about the Beverage antennas, super long wire receiving antennas thar are unidirectional and have a very low noise that makes this antenna excellent for low band dxing. By Thomas R. Sundstrom W2XQ, 73, June 1981, 73 Magazine

Learn about the practical design and construction of Yagi antennas for ham radio operators. This post explores the benefits of Yagi antennas in receiving and transmitting RF signals, concentrating signal energy in one direction for long-distance communication. Discover the theory behind Yagi antennae, the importance of element size and spacing, and the resources available for sizing and construction. Whether you're interested in OTA television or amateur radio communication, understanding Yagi antenna design can enhance your signal reception and transmission capabilities.

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

This study details a reception comparison between vertical and horizontal active loop antennas, specifically two identical _Wellgood active loop antennas_, on various HF bands. The experiment, conducted in a densely populated QRM-prone area, monitored FT8 signals over a 24-hour period using two identical receivers. The methodology involved direct comparison of signal reception across the HF spectrum, aiming to identify performance differences based on antenna orientation. The results indicate that vertical loops demonstrated superior performance on higher bands (10m, 15m, 20m), while horizontal loops excelled on lower bands (30m, 40m, 160m), particularly for receiving long-distance (DX) signals. The horizontal loop's advantage on lower bands is attributed to potentially better low-angle performance and reduced sensitivity to man-made noise, yielding a **2-3 S-unit** improvement on 160m. The study provides practical insights for optimizing antenna placement in challenging urban environments, noting that the horizontal loop consistently showed a **10-15 dB** signal-to-noise ratio improvement on lower bands.

IAT is an excel sheet table evaluate parameters of VHF UHF antennas edited by Vladimir UR5EAZ. The difference between this tool and the existing VE7BQH Antenna Table is the use of G / T and C / N instead of the G / Ta parameter. In this table, Vladimir applies the ITU recommendations to assess the noise properties of a radio receiving system and shows the advantage of the G / T concept over the G / Ta concept when choosing an antenna.

A home made Beverage system for portable use. The goal was to switch between 4 single Beverage antennas without interfering on the other receiving stations.

Chokes and isolation transformers are essential for receiving antennas to mitigate common mode current, which induces noise and interferes with signal quality. Common mode chokes, formed by winding feedline through ferrite cores, block unwanted current effectively. Proper selection of core material and winding turns ensures resonance near the operating frequency, reducing interference. Isolation transformers further minimize interference, crucial for multi-transmitter stations.

The article discusses the evolution of antenna designs, specifically focusing on the upgrade from the W7IUV rotatable Flag to the Waller Flag. Author Pierluigi Mansutti IV3PRK shares insights on modeling these antennas using EZNEC software, detailing their performance in noisy environments. The W7IUV Flag proved effective for receiving signals, while the Waller Flag, developed by NX4D and N4IS, offers improved front-to-back ratios but requires careful consideration of signal levels and noise management. The article emphasizes practical modeling results and interactions between different antenna setups.

This article explores Beverage antennas, a type used for low-frequency radio reception. Despite the mystique, they are relatively simple wire antennas placed near the ground. Their key benefit is improved signal-to-noise ratio by rejecting unwanted signals. While lengthier antennas offer better reception, even shorter versions (around 200 feet) can improve DX reception compared to traditional antennas.

This FAQ covers building and buying transformers for loop-on-ground and Beverage antennas. Building one uses ferrite cores and thin wire. Buying is an option, with the DX Engineering BFS-1 being recommended. These transformers isolate the antenna from the cable to prevent unwanted signal pickup.

Details the construction and performance of a phase-controlled receiving array, specifically a **MicroSWA** variant, optimized for QRP low band fox hunting on 40M and 80M. The resource documents the author's iterative design process, addressing significant regional noise challenges encountered during 0100-0230 UTC fox hunt periods. Initial experiments involved a director wire on a 40M vertical, yielding limited improvement, prompting a shift towards advanced null-steering techniques. The project leverages concepts from Victor Misek’s "The Beverage Antenna Handbook" and Dallas Lankford’s extensive work on phased receiving antennas for urban lots. A key modification involved integrating a new passive phase control box and a push-pull **Norton common base preamp** using 2N5109 transistors, designed for high third-order intercept performance to maintain weak signal integrity amidst strong adjacent signals. The system incorporates Faraday-shielded transformers with RG174 primaries on -75 ferrite cores, housed in ABS plastic pipe. Performance tests confirmed the MicroSWA's ability to produce deep, steerable nulls, achieving approximately 30 dB noise reduction on 160M, 80M, and 40M. This enabled detection of QRP signals undetectable on conventional transmit antennas. The final unit includes front panel controls, a 10-11 dB preamp, and a robust power conditioner, demonstrating effective noise mitigation for challenging low band QRP operations.

This article discusses the Beverage antenna, a reception antenna for low bands, originally published in the Megahertz magazine between November 1990 and April 1991. It explains the challenges faced in receiving signals on low bands due to interference and how the Beverage antenna's directional radiation pattern can help improve reception of distant stations. The article highlights the importance of choosing antennas with low efficiency but sharp radiation lobes for better DX signal reception. It also compares the reception characteristics of signals from European stations versus DX stations, emphasizing the benefits of antennas favoring low arrival angles for DX signals on low bands.