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A cost effective current-mode 1:1 balun can be constructed from a length of coax and a rod typically used for a broadcast antenna loop-stick, some electrical tape, cable ties, a length of PVC water-pipe and some connectors.

Selecting an appropriate antenna system for shortwave broadcasting involves evaluating various types based on performance, cost, and operational parameters. This resource details the critical specifications for broadcast antennas, including average and peak power ratings, directivity, takeoff angle (TOA), horizontal beamwidth, and gain, emphasizing that a 100-kW transmitter requires an antenna rated for 150 kW average and 400 kW peak. It clarifies that low TOA signals travel thousands of kilometers, while high TOA is for local coverage, and nearly all modern shortwave broadcast antennas are horizontally polarized. The article explores specific antenna types, such as Log-Periodic Antennas (LPAs), which offer wide frequency ranges (e.g., 2-30 MHz) and directional patterns with 11 dBi gain, costing from $20K to over $100K for multi-curtain versions. Dipole arrays, also known as curtain antennas, are prevalent in international broadcasting, featuring steerable beams (±15° and ±30°) and mode-switching capabilities to alter TOA, with high/low pairs costing over $1 million. Fan dipoles are noted for omnidirectional patterns, smaller size, and lower cost for low-power applications, while rhombics, though simple, require resistive termination and incur several dB of I2R losses. Balun considerations are crucial, as most communications baluns are not rated for the higher average and peak powers of AM broadcast transmitters. Modern shortwave antennas utilize durable materials like Alumoweld wire rope for radiators and support elements, avoiding copper, fiberglass, or materials prone to stretching or deterioration. Feeder systems for high-power stations often require tapered-line baluns to convert 50-ohm unbalanced power to 300-ohm balanced for connection to the antenna.

A rotary trapped-dipole for 17 and 20 meters, as described by IZ7ATH, presents a practical solution for multi-band HF operation. The author, Talino, recounts his experience building this antenna for IK7ZCQ, detailing the evolution from an initial concept involving a grounded-driven element and gamma-match to a direct-fed, non-grounded design. His pragmatic approach, adapting available materials, is evident throughout the construction narrative, particularly with the use of eight tapered aluminum pipes for the driven element. Construction specifics include precise measurements for the aluminum tubing, with diameters ranging from 30 mm down to 16 mm, and a critical note on reducing tip thickness for weight optimization. The _traps_, initially a concern, are fabricated using 8 turns of RG58 coax on a 27 mm support, tuned to resonate at 18.1 MHz using a dip-meter. Talino emphasizes sealing the traps with RF glue and PVC tape to prevent water ingress, a crucial step for longevity. Field test results, conducted on a 10-meter pole in a clear garden environment, showed an SWR of 1.2:1 on 17 meters and 1.5:1 at 14.200 MHz. While SWR varied slightly when installed at Mario's QTH due to nearby objects, the antenna's performance remained commendable. The final half-dipole length is 46 cm for the 18 MHz tips, and the total weight is under 6 kg, with potential for further reduction.

A cost effective current-mode 1:4 balun can be constructed from two lengths of coax, two ferrite rods, some electrical tape, cable ties, a length of PVC water-pipe and some connectors. This form of 1:4 current-mode balun is named after G. Guanella.

A 144 MHz dipole antenna made from coax, PVC pipe, and aluminum foil tape

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

This resource details the computer-optimized design of the _ZS6BKW_ multiband dipole, an evolution of the classic _G5RV_ antenna. It begins by referencing the original 1958 RSGB Bulletin article by Louis Varney G5RV, explaining the operational principles of the G5RV's flat-top and open-wire feedline on 20m and 40m, noting its impedance transformation characteristics for valve amplifiers of that era. The article then transitions to the rationale for optimizing the design for contemporary solid-state transceivers requiring a 50 Ohm match. The core of the project involves using computer modeling to determine optimal lengths for the flat-top and matching section, aiming for a VSWR of less than 2:1 on multiple HF bands. It discusses the process of calculating feedpoint impedance based on antenna length and frequency, referencing professional literature from Professor R.W.P. King at Harvard University. The analysis also considers the characteristic impedance (Z(O)) of the open-wire line, identifying a broad peak of adequate values between 275 and 400 Ohms. Specific design parameters for the improved ZS6BKW are presented, including a shorter flat-top and a longer matching section compared to the original G5RV, with a velocity factor of 0.85 for the 300 Ohm tape. The article confirms acceptable matches on 7, 14, 18, 24, and 28 MHz bands when erected horizontally at 13m, and also discusses performance in an inverted-V configuration, noting frequency shifts. The author, Brian Austin ZS6BKW, emphasizes the antenna's suitability for modern 50 Ohm coaxial cable without a balun.

A simple center-fed dipole made just with a thin-wall PVC pipe, aluminum tape, and RG-8X coax

2M Yagi made from Measuing Tape by NT1K

Manufacture Fibreglass Rods poles Tapered Fibreglass Rods apply flag poles, Tent poles, Golf flag poles, Sail Battens, Skifield barriers, Kite struts, Sports field markers, Fishing rods.

Antique radios, ham radio, electronic parts, test equipment, stereo equipment, record players, phonographs, tape recorders, gadgets, Bought & Sold Online

One point eight MHz to 30 MHz is the operational bandwidth for this 4:1 Ruthroff voltage balun, designed to interface an unbalanced T-Match network with a balanced antenna system. The project details the construction using a _T200-2_ powdered iron toroid core, tightly wrapped in PVC electrical tape for insulation, and wound with 17 double bifilar turns of 1.25mm enamelled copper wire. This outboard balun offers flexibility, allowing hams to trial various baluns based on antenna system and impedance characteristics, rather than integrating it directly into the tuner. The resource includes a schematic of the balun, a wiring diagram showing winding connections, and a table suggesting alternative toroid cores like the T80-2 or T400-2 with corresponding winding counts. Component sourcing is straightforward, listing items such as the _Amidon_ T-200-2 core, SO-239 connector, and a sealed polycarbonate enclosure from Jaycar. Performance evaluation was conducted using an _AIM 4170C_ antenna analyser, demonstrating efficient 1:4 voltage transformation across the specified HF spectrum. Further efficiency tests involved measuring RF power loss at various frequencies, revealing minimal loss—less than 0.7 dB from 3.6 MHz to 30 MHz, and only 2.0 dB at 1.8 MHz. These measurements, performed under ideal 50-ohm conditions, confirm the balun's effectiveness as a low-loss interface for multi-band antenna systems. The page also links to several other balun and unun projects, including 1:1 current and voltage baluns, and 9:1 voltage ununs, providing a broader context for impedance matching solutions.

An off-center-fed sleeve dipole, made of CPVC and aluminum foil tape by KV5R

This resource provides a unique historical audio archive of 50 MHz DX contacts, documenting significant F2 and Es propagation events experienced by PA2S (formerly PA2HJS) since 1978. The collection includes recordings of beacons and two-way QSOs with stations across North America, South America, Asia, Australia, Europe, and Africa. Specific entries detail contacts with rare DX entities such as ZS6PW, VE1AVX, C5AEH, J52US, TR8CA, LU8MBL, VK8ZLX, and various Japanese stations, often noting the mode (SSB or CW) and propagation type. The archive also highlights challenging pile-up situations and frustrating near-misses during major openings. The recordings, initially in RealAudio format for solar cycles 21 and 22 and later in MP3 for cycle 23, offer a practical illustration of 6-meter band conditions over several solar cycles. The content allows hams to listen to actual signals from different continents, observing signal characteristics like typical TEP fading from 5H3RA or strong F2 backscatter from OZ1BVW. It provides a comparative perspective on propagation effectiveness between solar cycles, noting that cycle 23, while not as robust as previous cycles, still yielded interesting openings. The archive serves as a valuable educational tool for understanding real-world 50 MHz DXing and propagation phenomena.

Distributor of ESD, kapton tapes, high temperature tapes, esd wrist straps, ionizers, ground cords, grounding devices, ESD gloves, esd finger cots, esd workstations, esd rubber bands, esd binders, esd bags, anti static glove, esd rubber bands, no clean solder paste, water soluble solder paste, finger cots, esd mats

Cheap and light portable 2m Yagi

Tape measurement yagi. The longest part is 530 mm, easy fit to your backpack. Very easy and fast deploy. Great for SOTA and portable operation. Can be used in horizontal or vertical polarization. Based on DK7ZB design

A presentation of the Yagi Antennas, and other interesting tid-bits by Brian Mileshosky. The document provides an in-depth exploration of the Yagi-Uda antenna, detailing its historical development, design principles, and performance characteristics. Originally described in the 1920s, the Yagi antenna features a driven element and parasitic elements, including reflectors and directors, which collectively determine its behavior. The document highlights how element lengths, diameters, and spacing influence gain, impedance, and directivity. It also discusses the antenna's reciprocal nature and presents data on typical gain values for various element configurations. Additionally, the text covers practical considerations, such as the construction of a "Tape Measure Yagi" for amateur use, and touches on related antenna types like dipoles and their application in Near Vertical Incident Skywave (NVIS) communication.

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

A Tape Measure Beam Antenna for Radio Direction Finding based on WB2HOL design.

New IOTApedition: 10 - 15 January 2006

This resource, despite its title, does not provide information relevant to amateur radio operations or the W1BD Central Vermont Amateur Radio Club. Instead, the content focuses on commercial topics such as vinyl lettering, business signage, and brand recognition strategies. It details the application of _transfer tape_ for graphics, the importance of pre-masking in vinyl cutting, and the use of squeegees for smooth decal application. The site also discusses various types of business signs, including monument signs and awning signs, highlighting their role in attracting customers and establishing brand presence. Further sections delve into home maintenance tasks like gutter cleaning, offering advice on using power washers and the importance of safety measures when working on ladders. The content also explores strategies for building brand recognition and customer loyalty, emphasizing consistent marketing efforts and excellent customer service. It touches upon the use of custom-printed bags and digital displays, such as LED signs, for enhanced visibility and engagement. The site's articles include practical tips for kitchen renovations, such as upgrading cabinet hardware, adding pendant lighting, and repainting cabinets to achieve a fresh look without significant expense. The content is entirely unrelated to amateur radio activities, club information, or technical aspects of radio communication.

Yamuna Cable Accessories Pvt. Ltd. specializes in the development, manufacturing, and marketing of power cable accessories, including a comprehensive range of cable jointing kits and components. The product line encompasses _Heat Shrink_ and _Cold Shrink_ cable joints, heat shrinkable tubing, pre-moulded slip-on joints, resin pour, and Tapex systems, all designed for applications up to 66 kV. The company highlights its ISO 9001-2015 certification, signifying adherence to international quality management standards in its manufacturing processes. The resource details specific product categories such as end caps, insulation piercing connectors, copper mesh, fireproof coatings, tubing and components, lugs and ferrules, and safety products. It also features specialized items like _Elbow Connectors_ rated for 25 kV-250, 400, and 630 amps, and various types of tinned copper braid used for grounding and electrical shielding. The site provides an overview of their manufacturing capabilities and global presence across 40+ countries. Established in 1973, Yamuna Densons has over four decades of experience in the industry, positioning itself as a significant designer, manufacturer, and supplier of insulators, tabs, and cable jointing systems in India. The company emphasizes its role as a leading exporter of these products, serving both domestic and international clients.

An unique method to listen to QRSS signals is... using an old tape recorder with variable speed

This is a design based on the QuickYagi 4 software by WA7RAI with some changes for practical reasons. The beam uses 6.5 metres of standard 25mm square boom, 12mm diameter elements without tapers. The actual boom length used is 6.3 metres and all parts are readily available.

Over 1000 _Elecraft_ KX2 owners have benefited from the Kx22 Heatsink, experiencing cooler rig temperatures and higher output powers. PAE manufactures these heatsinks, along with AC power supplies for HF transceivers, remote power relays, and Ethernet relays, with all machined products manufactured in the **USA**. PAE distributes _Fair-Rite_ Mix 31 ferrite snap-it cores and toroid cores, essential for RFI suppression and impedance matching in amateur radio setups. The product line also includes commercial monitoring antennas, UQUI transformers, ULP AC power filters, and 3M conductive adhesive copper tape, catering to various station build-out and maintenance needs. The AM1 Portable Antenna Mount System and its AM1-VA Multi-Angle Adapter offer flexible antenna deployment options. PAE ensures careful packing of fragile ferrite products, with shipping cost adjustments communicated post-order for larger, heavier combinations to guarantee safe delivery.

Demonstrates the construction and portable deployment of a 40-meter horizontal loop antenna, often referred to as a "Sky Loop" or "DX-Buster." The design adapts a full-wavelength horizontal loop for field use, eliminating the need for traditional insulators by employing four 5-meter heavy-duty _squid poles_ and metal post bases for support. This setup facilitates rapid assembly, crucial for portable operations, with the antenna wire length specified at approximately 43-45 meters for optimal 40-meter band performance. The resource details the specific construction methodology, including winding the antenna wire around rubber caps on the squid poles and securing it with electrical tape. It provides a parts list and assembly techniques, focusing on minimizing components for ease of transport and quick setup. The article, originally published in the February 2013 edition of the Central Coast ARC "Smoke Signals" magazine, reflects practical experience. This documentation offers a field-deployable 40-meter loop antenna solution, utilizing readily available components like fiberglass squid poles. It presents a practical approach for operators seeking a robust, portable antenna for the 40-meter band, emphasizing simplicity and efficiency in its design and deployment.

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.

Explore the world of fox hunting with the Fox Hunt V7 Kits and Assembled Units. Learn about the different antennas used for fox hunting, such as the tape measure beam with an offset attenuator. Discover how to make your own WB2HOL beam antenna using PVC pipe, T's, and a tape measure. Find out how the offset attenuator works and how it can help you track down jammers and interference. Whether you're a seasoned fox hunter or just starting out, this page offers valuable insights and tips for improving your hunting skills.

145 MHz is the target frequency for this 2-meter Skeleton Slot Yagi Stack antenna project. The design focuses on feeding two stacked Yagi antennas using a skeleton slot radiator, which is a unique approach for VHF enthusiasts. The project details the construction process, including the loop tapered matching section for impedance matching, ensuring optimal performance. The use of specific components like the EH789 element holder and MB456 main mast bracket is highlighted, providing clarity on the assembly process. The construction utilizes 20x20 box aluminum bar for durability and precision. Key dimensions, such as the element length (ER-ED4) and main boom spacing (MM123), are meticulously outlined. This attention to detail aids in replicating the antenna design accurately. The downloadable PDF offers comprehensive instructions, making it accessible for amateur radio operators interested in VHF antenna construction. This project is particularly beneficial for those looking to optimize their 2-meter band operations. The inclusion of a skeleton slot radiator and loop tapered matching section demonstrates advanced techniques in antenna design, catering to both intermediate and advanced builders.

The project details the construction of a small, portable **CW decoder** built around an Arduino Nano and an LM567 tone decoder circuit. It integrates an OLED display for output and is powered by a 1200 mAh Li-Po battery. The Arduino Nano is programmed with a modified version of the OST Morse Box firmware, originally based on Budd, WB7FHC's work, provided as a HEX file for flashing. The LM567 output connects to Arduino pin D2, while pins A6 and A7 are grounded due to the absence of potentiometers, simplifying the circuit. Standard I2C connections are used for the OLED: SDA to A4 and SCL to A5. The entire assembly, including the Arduino, OLED, and decoder circuit, is mounted on a perfboard to fit precisely within an old cassette tape box. This design emphasizes portability and compact form factor. Parameters for the decoder can be adjusted using a dedicated Windows Control program, offering flexibility in operation. The resource provides practical insights into adapting existing firmware for specific hardware constraints and achieving a self-contained, battery-powered **Morse code** decoding solution.