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WB5NHL describes setting up a 160-meter antenna on a small suburban lot, where standard options like Beverage antennas and 1/4 wavelength verticals require extensive space and ground systems. Instead, Guy Olinger's Folded Counterpoise (FCP) provides a solution. The FCP minimizes ground losses by using a folded wire design, allowing effective antenna placement in limited space. The FCP, fed with an isolation transformer, enabled WB5NHL's first 160-meter antenna installation, offering improved performance despite space constraints.

This webpage offers an online antenna designer tool to calculate the dimensions for constructing a double bi-quad antenna for various frequencies. The directional antenna is suitable for UHF and higher frequencies, such as WiFi, UMTS, LORA, and mobile phone networks. It provides dimensions based on the input frequency, making it ideal for hams looking to build their own antennas for specific applications. The tool also mentions using common household materials like copper wire for construction, making it accessible for amateur radio operators with basic equipment.

The tri-band trapped delta loop antenna design operates on 80 meters (3.5–4 MHz), 40 meters (7–7.3 MHz), and 30 meters (10.1–10.15 MHz) using a single triangular wire loop. This configuration eliminates the need for an external antenna tuner or band-switching relays. The antenna's physical perimeter, approximately 270 feet, establishes 80M as the fundamental band, with specific trap placements enabling resonance on 40M and 30M. Trap design and placement are critical, with 30M traps positioned inboard of 40M traps within the horizontal element. Each slant leg measures approximately 80 feet. The resource references foundational information from the _ARRL Antenna Handbook_ and _ON4UN’s Low Band DXing_ regarding full-wave loop behavior and feedpoint impedances. The project aims to provide multi-band HF operation from a single, fixed antenna structure.

Approximately 3 minutes of video content, originally from _Aruba Networks_, illustrates fundamental principles of antenna gain and radiation patterns. While the source material targets broadband wireless, the underlying physics of RF energy directionality and signal shaping are universally applicable to amateur radio antenna systems across various frequencies. Antenna gain is crucial for maximizing effective radiated power (ERP) without simply increasing transmitter output. The resource explains how elements in a Yagi beam, for instance, absorb and re-radiate RF energy, cumulatively increasing signal amplitude in a desired direction. This process enhances both transmit efficiency and receive sensitivity, directly impacting DX capabilities and overall station performance. Understanding these concepts is paramount for any radio amateur, as the antenna system often represents the most significant factor in a station's operational effectiveness. The article emphasizes that careful calculation and positioning of parasitic elements can dramatically reshape an antenna's radiation pattern, leading to substantial improvements in signal strength and reach.

Details the construction of a portable 6-meter 4-element quad antenna, specifically designed for VHF and Field Day operations. The design emphasizes portability and rapid field assembly, utilizing a 10-foot boom, #12 bare wire elements, and fiberglass electric fence post spreaders. It presents specific dimensions for reflector, driven element, and directors, including spreader lengths, circumferences, and corner marks, all derived from a G0KSC design and modeled in EZNEC. The resource outlines the fabrication of synthetic lumber hubs that allow post-assembly adjustments along the boom, and describes spreader clamps made from ¾” OD fiberglass rod, drilled and tapped for 8-32 nylon thumbscrews to secure element wires. It provides instructions for reducing spreader ends to 0.370” OD for proper fit and details the assembly of the boom from two 1½” OD x 6’ aluminum tubes. Performance data from EZNEC modeling indicates a gain of 10.25 dBi (8.1 dBd) and a 20 dB F/B ratio at 50.150 MHz, with SWR values of 1.08, 1.09, and 1.11 at 50, 50.15, and 50.5 MHz respectively. The document includes a field test report from Field Day 2010, where the antenna was deployed at 21 feet, showing an SWR resonance 200 KHz below EZNEC predictions. It notes successful 5-watt QSOs into New York and Canada from Tennessee, highlighting the antenna's excellent directivity and gain compared to a 4 dBd Moxon. The antenna breaks down into easily transportable components, including two 5’ boom sections, a 3’ boom connector, 16 spreaders, and four element/spreader clamp assemblies.

The article explains how to adapt the YAESU FT817 transceiver so that it can be used to control Kuhne electronic transverters by transmitting at +12V via the coaxial wire. Different FT817 versions imply that some of the modification proposals that have been made so far don't apply to everyone. This tutorial provides a workaround that works with all FT817 models. It makes use of the external ACC socket, connecting an interior tiny circuit board to two thin wires. Follow ON7WP's instructions for using the rear antenna socket.

Details the construction of a Copper Cactus Dual-Band Super J-Pole Antenna, providing specific measurements for 1/2-inch copper tubing sections, including a 57-1/2-inch long section and a 19-inch short section, along with a 42-inch piece of 3/16-inch or 1/4-inch soft copper tubing for the matching stub. It covers soldering techniques for copper fittings, drilling an SO-239 panel mount coaxial fitting, and securing feed point connections with stainless steel adjustable band clamps. The resource specifies materials such as Schedule M 1/2-inch copper tubing, various copper fittings, a hardwood dowel or Fiberglas rod for insulation, and #14 stranded copper wire for the feed point. The guide simplifies the J-pole feed point by using an SO-239 fitting with an elongated mounting hole and band clamps, noting an optimal feed point distance of approximately 3 inches above the crossbar for proper impedance matching. It recommends a 4-turn coax choke, 5 inches in diameter, placed within 3 to 4 inches of the feed point for 2-meter operation to mitigate RF on the feedline. The project emphasizes weather sealing with silicon or butyl rubber compound and clear lacquer for durability and appearance.

VE1ZAC's analysis details the performance of **MFJ927** and **SGC239** autotuners with portable HF vertical antennas, specifically comparing 31 ft and 43 ft configurations. The resource originated from challenges encountered during a Maritime QSO Party roving operation, necessitating a lightweight and easily deployable antenna system. Target bands for the contest included 80, 40, 20, 15, and 10 meters, with a maximum power handling of 100 W CW. The author utilized a 30-foot carbon fiber push-up pole to support a vertical wire element, noting its 2 lb weight and reliability. EZNEC modeling was employed to predict performance, showing favorable results for a 30-foot vertical with elevated radials, particularly on 40 and 20 meters. Feedpoint impedance measurements, taken with an AIM4170C, are presented for various HF bands, both with and without a 41-foot RG6 stub designed to reduce reactance on 80 and 20 meters. The stub significantly improved matching on these bands, easing the tuner's workload. Operational tests revealed issues with the MFJ927's reliability during contest setup, leading to reliance on the K3's internal tuner. The SGC239, tested post-contest, performed flawlessly. A detailed side-by-side comparison covers mechanical aspects, connection options, power bias, impedance range, board quality, and documentation. Modifications to the MFJ927, including a new aluminum case, white paint for heat reduction, and upgraded impedance-measuring resistors, are also described.

This article discusses the design and implementation of a 2-element wire beam antenna for the 20 meter band, suitable for field day operations with 4 Switchable Directions. The antenna is configured with sloped wires in an inverted V shape, with a specific design to achieve directional properties. The author tested the antenna design using MMANA and NEC2 software, based on a solution published in QST. Detailed diagrams and instructions are provided for constructing the antenna on top of a 12 meter mast, with specific wire lengths and positioning to ensure optimal performance. This resource is valuable for hams looking to build a directional antenna for the 20m band and improve their field day setup.

Cloverleaf antenna is a circular polarized antenna which is way better than the cheap dipole antenna that comes with video transmitters and receivers. The Cloverleaf is a closed loop antenna which the signal and ground wires are connected. The cloverleaf antenna has 3 loops at 120 degree apart, and they are titled at 45 degree to horizontal plane.

Effective suppression of harmonics and parasitic radiation from HF transmitters is crucial, especially with the increasing sensitivity of VHF/UHF radio channels to interference. This project details a hybrid low-pass filter (LPF) designed to operate across the HF bands up to 51 MHz, making it suitable for 6-meter band operations while providing deep VHF/UHF suppression. The design addresses the challenge of modern interference landscapes, where even microvolt-level signals can disrupt wireless sensors and other simple VHF/UHF receivers. The filter utilizes a single elliptic link, combining high cutoff steepness with robust suppression in the hundreds of megahertz range. A key feature is the use of only two standard capacitor values, simplifying construction and component sourcing. The article provides a detailed schematic, performance characteristics, and _RFSim99_ model file, demonstrating a reflection coefficient S11 below 0.017 (VSWR < 1.03) across 1-51 MHz, ensuring minimal degradation to the antenna system. Construction notes include coil winding specifications and capacitor selection guidance, with recommendations for _FR-4_ assembly. Two capacitor sets are presented, with the first variant recommended for its lower RF current demands, keeping currents below 3 A at 1 kW passing power at 51 MHz. Fine-tuning involves adjusting frameless coils, with considerations for capacitor tolerance and high-frequency capacitance measurement accuracy.

W1JR-style common mode chokes are versatile tools for antenna experimentation. Three variants were constructed using RK4 ferrite cores and RG303 Teflon coax, differing only in output terminals: banana connectors for dipoles, N-connectors for antennas with existing terminals, and bolts with washers for vertical antennas. Materials included junction boxes, terminals, and small hardware. Assembly involves maximizing windings on the core, securing with ties, and gluing components. Improvements included switching to multi-stranded wire for durability. These chokes provide efficient, customizable solutions for various antenna setups.

This article demonstrates how to convert an existing tower into a dual-band vertical antenna for 80- and 160-meter DX operation. Using EZNEC modeling and practical design principles, the authors achieved a low-profile, efficient setup with a single coax feed line, no moving parts, and optimal radiation patterns. The system integrates an 80-meter vertical wire and a 160-meter shunt-fed gamma match for simultaneous operation. Detailed construction insights, including feed system and capacitor configurations, offer a reliable, full-legal-power solution.

Details the installation and operation of the DX Engineering TFS Series Transmit Four Square System Phasing Units, specifically models like the DXE-TFS4-160B, DXE-TFS4-80B, and DXE-TFS4-40B. It covers system components, required parts, and a discussion of vertical antenna selection, including a table of suitable DX Engineering Monoband Vertical Antennas. Installation procedures are outlined, encompassing site selection, four square layout, topographical considerations, and noise source mitigation. Specific instructions are provided for mounting the phasing unit, antenna feedline connections using 1/4-wave 75-ohm coaxial cables, and control wire routing. The document also includes details on radial system implementation, with a table of radial wire lengths for 160, 80, 75, and 40 meters, and procedures for tuning the vertical antennas for optimal performance. Operational aspects of the Four Square Control Console are described, including front and rear panel functions, control logic (Table 4), and typical transceiver/amplifier interconnections. The system enables directional control with approximately 5 dB gain over a single vertical element in four directions or an omni-directional pattern, achieving typical front-to-back ratios exceeding 20 dB. Lightning protection and initial system testing are also addressed, along with a 5 kW CW and 10 kW PEP SSB power rating and hot switching lockout feature.

Moto-QRP setups offer compact, weatherproof QRP transceivers for portable ham radio use, ideal for motorcycle and backpack operations. The YouKits HB1A MKII, a 5W CW rig, is paired with a lightweight long-wire antenna and an Elecraft T1 tuner for efficient field communication. This setup fits in panniers, enabling operators to explore parks and remote locations. Accessories include a durable Morse paddle, FCC documentation, and essential logging tools, making it a perfect choice for adventurous QRP enthusiasts.

A full-wave delta loop antenna, approximately 141 feet in total wire length for the 40-meter band, offers a low angle of radiation, which is highly advantageous for DX operations. This design, optimized for both 30m and 40m, leverages a specific circumference calculation of 1005/F, ensuring resonance on both bands through a simple switching mechanism. The antenna's configuration enhances long-distance communication, making it a practical choice for hams with limited space. The resource details the construction process, including the use of a _Ceramic Knife Switch_ for band selection and an _RG-11_ matching section to achieve optimal impedance. It outlines the precise loop lengths required for each band, along with tuning secrets to ensure efficient operation. Requiring a minimum height of 12 feet, this antenna can be supported by a single mast or tree limb, making it suitable for suburban installations where stealth or space constraints are a factor.

This resource presents the design and characteristics of the K9AY Terminated Loop, a compact directional receiving antenna system. The document details the antenna's physical and electrical configuration, consisting of a wire loop, a 9:1 impedance-matching transformer, and a terminating resistor. It describes how the antenna achieves directionality, favoring signals from the feed point end and rejecting signals from the terminating resistor end by several S units. The system is designed for low-band operation, specifically mentioning its application for improving reception on bands where space is a constraint. A four-direction system, utilizing two loops oriented at right angles with a relay-controlled switching system, is discussed. The resource includes a comparison of the K9AY loop's footprint to that of an equivalent EWE array, indicating the K9AY system requires approximately 1/7 the area while maintaining similar directional patterns. The design prioritizes signal collection sufficient for use with modest preamps, such as those integrated into HF transceivers. The article was originally published in QST in 1997.

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 page describes N6AQ's experience with a 160-meter doublet antenna from True Ladder Line. The operator initially attempted to install the antenna in a tree but later changed to a Rohn 45 tower for support. The antenna was upgraded to use 14ga wire instead of 16ga, and the performance was tested using an IC7300 transceiver with a 4:1 balun. Despite less than ideal setup conditions, the operator received positive signal reports on 40, 80, and 160 meters, thanks to advice from Gary at True Ladder Line.

This project outlines a simple, cost-effective 40m band HF dipole antenna design, ideal for beginners. Constructed with insulated copper wire and a 1:1 balun, it offers a 50-ohm impedance, suitable for both 40m and 15m bands due to the harmonic relationship. Calculations account for a K factor, ensuring optimal length and performance. Antenna modeling with 4NEC2 confirms practical access to both bands, though real-world results may vary. Lightweight materials and straightforward assembly make it an accessible and versatile amateur radio solution.

The Zeppelin antenna, a J-type design, is presented as a two-band HF dipole, offering independent operation on harmonically related frequencies. This resource details its electrical configuration, comprising a half-wave radiator end-fed by a quarter-wave matching section, and explores its historical evolution from early Zeppelin airship applications to modern amateur radio use. The article specifically examines how a Zepp antenna tuned to 28.4 MHz (10 meters) exhibits a harmonic relationship with 15.4 MHz (20 meters), noting a frequency ratio of approximately 1.84:1, which deviates from a perfect 2:1 due to factors like elevation, wire separation, velocity factor, and end-effect. Antenna modeling results, including SWR sweeps at 28.4 MHz (1.1 SWR) and 15.4 MHz (1.6 SWR), are provided through Graph 1 and Graph 2, illustrating the antenna's performance across these bands. Current distribution patterns for both the 28.4 MHz (second harmonic) and 15.4 MHz (first harmonic) operations are visually represented in Figure 2 and Figure 3, respectively. The author also includes a 4NEC2 model's "Symbol Conversion file" definitions and calculated #14 wire dimensions for achieving resonance at 28.4 MHz, with the antenna positioned at a height of 33 feet. The discussion further highlights the antenna's versatility, suggesting its potential as a single-band, center-fed, 15.4 MHz half-wave folded end dipole when fed at a specific low current point. This analysis provides practical insights into constructing and optimizing a multi-band Zepp antenna for HF operations, emphasizing its unique harmonic characteristics and physical compactness.

This paper presents an 80 meter wire 3-element beam antenna in an inverted-V configuration, designed for limited-height towers. Using EZNEC modeling, the antenna features a central parasitic reflector and two switchable driven elements at each end, enabling NE/SW coverage without moving parts or networks. Element lengths are optimized for SSB (3.8 MHz) and CW (3.5 MHz) operation, with a 50 Ω feed and rope-supported boom. The design delivers high gain, effective takeoff angles, and excellent reception, confirmed in real-world DX contest operation. Its simplicity, reliability, and ease of construction make it ideal for operators seeking performance without complex matching systems.

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.

The blog and website of English amateur radio operator G0RIF, located near Lichfield in central England. Favourite aspects of the hobby are DXing, RTTY, portable operating and experimenting with wire 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.

Presents an online retail platform for amateur radio operators, showcasing a diverse inventory of equipment and accessories. The site lists popular transceivers such as the _Icom IC-7300_ and _Icom IC-7610_, alongside various antenna solutions including base, HT, mobile, and end-fed designs. Operators can find coaxial cable, including bulk options and products from "The Wire Man," essential for shack setup. The platform also stocks crimping and stripping tools, adapters, and power supplies, crucial for station maintenance and construction. Test equipment like _RigExpert Analyzers_ and accessories such as Daiwa meters and _West Mountain Radio_ Power Poles are available. Additionally, the site offers software from _Ham Radio Deluxe_ and _RT Systems_, catering to logging and radio programming needs. Shipping policies include free shipping on C.Crane Radios and most orders over $100.00 within the lower 48 states, providing clear purchasing incentives.

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.

Tracing the foundational work of Guglielmo Marconi, this article details his early laboratory experiments in 1895, where he successfully transmitted wireless signals over 1.5 miles. It highlights his 1896 patent for a wireless telegraphy system in England and subsequent demonstrations, including signal transmissions up to 6.4 km (4 miles) on Salisbury Plain and nearly 14.5 km (9 miles) across the Bristol Channel. Marconi's work built upon the mathematical theories of _James Clerk Maxwell_ and the experimental results of _Heinrich Hertz_, proving the practical feasibility of radio communication. The resource further chronicles the formation of The Wireless Telegraph & Signal Company Limited in 1897 and Marconi's relentless efforts to popularize radiotelegraphy. A significant milestone was the 1901 transatlantic reception of the Morse code letter "S" from Poldhu, Cornwall, at St. John's, Newfoundland, using a kite-supported wire antenna, defying contemporary mathematical predictions about Earth's curvature limiting range. This achievement underscored the global potential of radio. The article also touches upon Marconi's later discoveries, such as the "daytime effect" concerning atmospheric reflection of radio waves, and his 1902 patent for a magnetic detector, which became a standard wireless receiver. His contributions earned him a Nobel Prize in 1909.

The article describes adding lightning protection to Beverage antennas, which are long wires susceptible to lightning strikes. The author reviews common lightning protection circuits and discusses their components. They then detail their design based on existing methods, highlighting choices for components and reasoning behind them. Finally, the author presents the completed design and its implementation on their Beverage antennas.

Early 20th-century transatlantic wireless communication efforts involved distinct technical approaches by Reginald Fessenden and Guglielmo Marconi. Marconi's systems, operational until approximately 1912, primarily utilized _spark technology_ for wireless telegraphy, facilitating Morse code communication between ships and across oceans. His Poldhu station in December 1901 radiated signals in the MF band around 850 kHz, later evolving to 272 kHz in October 1902, and eventually 45 kHz by late 1907 with increasingly larger antenna structures like the pyramidal monopole and capacitive top-loaded arrays. Fessenden, conversely, focused on _continuous wave transmission_ for wireless telephony, recognizing its necessity for speech. His transatlantic experiments in 1906 employed synchronous rotary-spark-gap transmitters and 420-foot umbrella top-loaded antennas at Brant Rock, MA, and Machrihanish, Scotland, tuned to approximately 80 kHz. Fessenden later utilized the _Alexanderson HF alternator_ at 75 kHz by late 1906 for pure CW transmission, integrating a carbon microphone for amplitude modulation. Receiver technology also differed, with Marconi initially relying on untuned coherer-type detectors, later developing the magnetic detector in 1902, while Fessenden's CW approach necessitated more advanced detection methods.

The 4m Slim Jim antenna project provides a construction guide for a low-cost, high-performance aerial designed specifically for the 70 MHz FM band. This design achieves a 1:1 SWR across the 4m FM band with straightforward adjustment of the feed point, utilizing RG-58 coax. Its low angle of radiation contributes to effective signal propagation. Construction involves using plastic knitting needles as spreaders and a telescopic fishing pole for support, with components secured using two-part epoxy. Annealed bare single-core copper wire forms the radiating element. The setup process includes raising the antenna at least 3 meters above ground for tuning, adjusting the RG-58 feed point for optimal SWR, and then soldering connections. Waterproofing is achieved with yacht varnish. The design emphasizes low wind resistance for durability, making it suitable for exposed outdoor installations. A PDF construction diagram is available to supplement the written instructions.