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End-Fed Half-Wave Antennas (EFHWAs) are analyzed for their utility in portable QRP operations, emphasizing their simplicity, efficiency, and predictable radiation patterns compared to other portable antenna types. The discussion contrasts EFHWAs with vertical antennas, random length wires, and center-fed dipoles, highlighting the common pitfalls of each, such as ground system dependency for verticals and feedline issues for dipoles. The article details the electrical half-wavelength calculation using the formula L (Ft) = 468/F(MHz) and explains how EFHWAs can be resonant on harmonic frequencies, enabling multiband operation. Various deployment configurations are presented, including the inverted L, inverted Vee, sloping wire, and vertical setups, each with specific advantages for radiation angle and polarization. For instance, a vertical EFHWA offers a low angle of radiation suitable for DX contacts without requiring an extensive ground system. The resource also addresses the counterpoise requirements, suggesting a quarter-wavelength wire or connection to a metallic structure for decoupling. A schematic diagram for a simple parallel-tuned circuit tuner, based on the _Rainbow Bridge/Tuner_ design, is provided, detailing component values for 30 and 40 meters, including a 6 microhenry toroidal inductor and a 20-100 picofarad mica compression capacitor. The tuner's adjustment process for SWR matching is also outlined.

The document details the optimization and construction of the _Maria Maluca_ antenna, a compact 6-band (20m-6m) directional beam. It presents a comparative analysis of shortwave antenna principles, highlighting the efficiency gains achieved by using an open feeder line and tuner as a resonant unit, contrasting this with the losses associated with traps or capacitive loads in multiband antennas. The resource specifically revisits an older South American 2-element design for 10, 15, and 20 meters, applying modern NEC-based software to develop a six-band version. Performance data is meticulously tabulated, showing impedance, free space gain, gain at 12m height, elevation angle, and front-to-back (F/B) ratio for each band from 20m through 6m. For instance, on 15m, the antenna achieves 5.1 dBd free space gain and 13.72 dB F/B ratio. The construction section provides practical guidance on element assembly using aluminum pipes and hose clamps, detailing the use of a heavy-duty glass fiber reinforced polyamide rod for electrical separation and bending strength. It also specifies the use of 450-ohm _Wireman_ line CQ 552 for the transmission line. The document includes diagrams for rod fixing, an air-wound balun, and a vertical elevation diagram for the 15m band, illustrating its DX qualification. It also discusses the antenna's suitability for portable and expedition operations, noting its compact transport dimensions (max 1.50m length, 12 lb weight) and quick assembly time (under 15 minutes). The author, Dipl.Ing. Helmut Oeller, DC6NY, is identified as a source for material kits.

This document provides a detailed guide on constructing and mounting a folded dipol for the 146 MHz frequency in a vertical configuration to be used in Yagi antennas. The step-by-step instructions and diagrams included make it easy for hams to build and set up this type of antenna. Understanding and implementing this design can enhance the performance of radio communication for Amateurs operating in the 2-meter band. Whether you are looking to improve your signal strength or experiment with antenna designs, this resource offers valuable insights and practical information.