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After a storm damaged the antenna, W6AER replaced it with a pre-made capacitance hat from DX Engineering. Using hose clamps and conductive grease, he ensured durability. Experimenting with radials and a coil, he aimed for better performance and resilience.

How to use a little known J-antenna characteristic to reduce a conventional 14 foot antenna to 7 feet. Perfect 50 Ohm match, same gain, no radials.

This is a plan for an optimized element UHF Yagi Antenna for UHF Bands featuring a 9dBd forward gain, a 13 dB front-back ratio, and a bandwith of 10 MHz on the 430-440MHz range.

EA4EOZ details the construction and testing of 50 MHz traps, a critical component for multiband antenna designs. The project addresses the challenge of sourcing high-voltage capacitors suitable for trap applications, exploring alternatives to expensive doorknob capacitors. The author successfully fabricated a capacitor using 1.6mm double-sided FR-4 PCB material, achieving a capacitance density of **2.6 pF/cm2**. Utilizing the _VE6YP calculator_, specific L and C values of 30 pF and 0.31 uH were determined for a 2cm diameter coil. Both the FR-4 PCB trap and a coaxial cable trap, constructed from _RG-58_, were built and tuned to approximately 50 MHz using a spectrum analyzer. The coaxial cable trap demonstrated superior performance, exhibiting a notch nearly **20dB deeper** than the FR-4 version. This practical comparison provides insights into trap construction for experimental antennas, with the coaxial cable trap selected for an antenna project intended for operation at up to 100 watts.

With increased ES propagation, this lightweight 5-element LFA antenna offers enhanced performance over the Bigwheel antenna's 5dBi gain, delivering approximately 11dBi and forward gain. Designed from G0KSC’s specifications, the 1.8m antenna was adapted for reduced weight using 6mm and 4mm rods instead of heavier tubes. 3D-printed PETG clamps ensure durability and precision, while the first tests showed excellent SWR and element coupling. Though built with a temporary Choke BalUn, the results were promising, with a Pawsey Stub BalUn planned next for further optimization.

A project for a six meters Yagi beam antenna, built mainly for portable operations. This is a 4 element Yagi beam with a 4 meters boom.

Explores the addition of a reflector to the traditional Hentenna design for 6m band, providing construction insights, performance comparisons, and modeling data

Paul McMahon details the design and construction of a four-element Yagi antenna for the 50-52.5 MHz range, published in Amateur Radio Magazine (Dec 2011). The antenna, featuring a raised driven element and a capacitive/DC connection using copper strips, maintains consistent VSWR and performance despite two years of weather exposure. The design utilizes inexpensive plumbing conduit for the boom and provides detailed construction guidelines, parts lists, and performance analysis through 4NEC2 simulations.

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.

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.

Fifty-one MHz operation, often called the "magic band," benefits significantly from a well-designed antenna, and this resource details the construction of a rigid 6-meter _Moxon antenna_ using common DIY store materials. The author, 4L/G8BAG, shares his experience with the 6m band, highlighting its potential for long-distance contacts, with single-hop sporadic E propagation enabling QSOs up to **2,500 km** and multi-hop contacts reaching **10,000 km**. The project emphasizes cost-effectiveness and durability, utilizing yellow gas pipe with an internal stainless steel lining for the antenna elements. The article provides specific dimensions for the Moxon rectangle, derived from the 12mm internal diameter of the gas pipe's steel core, rather than the outer plastic. It also details the use of white PVC water pipe for insulators and mounting, ensuring a tight fit with the yellow gas pipe. Initial testing with an MFJ antenna analyzer showed an excellent 1:1 SWR across the 50-52 MHz range, even when using 75 Ohm satellite cable as a feeder. The construction process is straightforward, involving cutting and bending the gas pipe, fitting insulators, and connecting the feedline. The author's successful on-air results, including a 1000 km contact with a temporary vertical, underscore the effectiveness of the 6m band and the Moxon design. The resource concludes with a note on exploring heavier gauge gas pipe for future 10m antenna projects.

The Acom 1500 HF+6M Linear Amplifier is a high-quality and user-friendly amplifier that provides excellent performance and reliability. G6NHU, who previously owned an Acom 1000, upgraded to the Acom 1500 after nine years and has been using it for about eighteen months. Key features highlighted include the ability to connect three antennas internally, straightforward tuning process, robust construction that can handle high SWR, quiet operation, fast and quiet switching for efficient CW operation, and clean output signal even when driven hard. G6NHU highly recommends the Acom 1500 and states they would not hesitate to purchase another one in the future.

The K5USS 6 Meter Hentenna Project page on Hamuniverse provides detailed instructions on how to build a 6 meter directional antenna with 3.5 dBd gain. The project is presented with permission from K5USS, Charlie of Richardson, Texas. This directional antenna is a full wave loop on 6 meters, horizontally polarized but mounted vertically, with a 50 ohm impedance, ideal for 6 meter SSB operations. The page is useful for hams looking to construct their own directional antenna for improved performance on the 6 meter band.

A small Yagi antenna for camper van. It is made of aluminum tubing, breaks down for storage, and works well for communicating with others. He built it in an afternoon and it gets good signal. The antenna is lightweight and can be packed up to fit inside his van while traveling

The RXC70/10 is a sensitive 70 MHz to 10-meterband converter using the Philips SA602 mixer IC. It operates with high stability and low noise, converting 70–72 MHz signals to 28–30 MHz for general coverage receivers. The compact, low-power design (15mA) supports various modulations and uses. Its versatility makes it suitable for amateur radio applications with proper tuning and antenna setup.

Guide to constructing an effective antenna for 50MHz. Inspired by a design from Martin DK7ZB, the article emphasizes the importance of precise measurements and quality materials. With a 2.20m boom and careful assembly, the antenna promises excellent performance, resilience, and cost-effectiveness, making it ideal for six meter band operations.

Learn how to enhance the performance of your Diamond V2000A antenna by optimizing the length of the radials. Discover a cost-effective method to create improved radials using simple materials like aluminum tubes and bolts. Explore the benefits of this modification for 6m band, unlocking triband capabilities and better SWR. Find out how a ham radio operator from Europe successfully upgraded their V2000 antenna and achieved impressive results. Save money by DIY-ing your radial enhancements instead of purchasing expensive replacements.

The XW4DX DXpedition website documents the amateur radio operation from Laos, a country ranked #98 on Clublog's Most Wanted list. This resource provides insights into the planning and execution of a significant DXpedition, including antenna choices like _Hexbeams_ at 14m, a 4-square for 40m, and a top-loaded vertical for 160m. The team, comprising operators such as _F4BKV Vincent_ and _F2DX Patrick_, focused on challenging paths, particularly towards the North American East Coast, where Laos is #41 most wanted. Operational constraints included prohibitions on 6m, 30m, 60m, and 80m bands within Laos, necessitating a focus on other HF frequencies, especially 160m and 40m. The expedition utilized up to five stations simultaneously, with equipment transportation being a major logistical challenge, partially mitigated by direct shipments from _Spiderbeam_ and donor support. The expedition ran from November 16th to 27th, 2023, with the complete XW4DX log uploaded to LoTW by December 23rd, 2023. This site serves as a historical record of their efforts to put Laos on the air for DXers worldwide.