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This PDF article from April 2001 QST details the construction of the "NJQRP Squirt," a reduced-size 80-meter inverted-V dipole antenna. The resource provides a general construction sketch, a photograph of the assembled antenna, and specific dimensions for PC-board insulators. The antenna consists of two wire legs, each approximately **34 feet long**, separated by 90 degrees, fed at the center. It is designed for operation on 80 meters (3.5-4.0 MHz) as a quarter-wavelength antenna, requiring a low-loss feedline and an external antenna tuner due to its non-resonant feedpoint impedance. Construction utilizes readily available materials, including 1/16-inch glass-epoxy PC board for end and center insulators, and #20 or #22 insulated hookup wire for the elements. The feedline specified is 300-ohm TV flat ribbon line, with a note on potential trimming for tuner compatibility. N2CX reports the antenna's center should be elevated to at least **20 feet**, with ends no lower than seven feet above ground, resulting in a ground footprint of approximately 50 feet wide. The design prioritizes NVIS propagation for local 80-meter contacts. DXZone Focus: PDF Article | 80m Inverted-V Dipole | Construction Notes | 34 ft element length

Presents the KE4UYP linear-loaded vertical antenna design, which introduces very little loss on 80 or 160 meters, achieving an overall radiation efficiency of 80% to 85%. This design addresses common pitfalls of traditional base-fed verticals by placing the majority of the current at the top of the antenna, eliminating the heavy reliance on extensive ground radial systems. The author's initial 10-meter model, only three feet tall, yielded 5/9 signal reports to Anchorage, AK, and Europe, confirming its effectiveness. The antenna incorporates both vertically and horizontally polarized radiators, with a 1/4 wavelength horizontal counterpoise located at the feed-point, near the top, to create an almost totally omnidirectional pattern with high wave angle horizontally polarized radiation. This dual polarization ensures even illumination across all take-off angles, making it effective for both local contacts and **DXing**. The vertical element is linear loaded, adding capacitance reactance and making it longer than the horizontal element to achieve resonance and raise the feed-point impedance to 50 ohms. Fine-tuning the antenna requires careful adjustment, as tower reactance can vary. The article suggests starting with 80 feet for 80m and 170 feet for 160m for the vertical wire, then trimming for resonance. Bandwidth specifications include 300 kHz under 2:1 **SWR** on 80m and 100 kHz on 160m when suspended between trees, or 150 kHz on 80m when side-mounted on a tower.

The ZS6BKW multiband HF antenna, a design by ZS6BKW (G0GSF), functions effectively on multiple HF bands without requiring an Antenna Tuning Unit (ATU) for 40, 20, 17, 12, 10, and 6 meters. This antenna, approximately **27.51 meters** (90 feet) long with a 12.2-meter (40-foot) open-wire feeder, is a direct descendant of the _G5RV_ but offers superior multi-band resonance. It can be deployed as a horizontal dipole or an inverted-vee, with the latter requiring only a single support and maintaining an apex angle of at least 90 degrees to prevent signal cancellation. Performance data, recorded with an MFJ Antenna Analyser, indicates SWR values of 1:1 on 7.00 MHz (40m) and 14.06 MHz (20m), with SWR below 1.3:1 on 17m, 10m, and 6m. While primarily designed for these bands, the antenna can be adapted for 80m, 30m, and 15m with an ATU, preferably at the balanced feeder's base. The use of 450-ohm twin-lead for the feeder is recommended over 300-ohm for improved strength and reduced losses, especially in adverse weather conditions. This design, originally published in _RadCom_ in 1993 and featured in Pat Hawker’s "Antenna Topics," provides a compact and efficient solution for HF operation, particularly for those with limited space or resources.

Presents the design and construction of the OK2FJ Bigatas, a portable, automatically tuned vertical antenna covering 80 through 10 meters. It details two distinct control systems: one utilizing BCD band data from Yaesu FT-857/897 transceivers, and another employing voltage level sensing for the Yaesu FT-817. The resource provides specific instructions for building the antenna's radiating element, loading coil with switchable taps, and the control circuitry, emphasizing the use of readily available components. The article outlines the physical construction of the antenna, including the use of duralumin tubes for the radiator and a PVC tube for the coil form. It specifies coil winding details, tap points, and the integration of radial wires for ground plane operation. The control electronics section provides schematics and component lists for both the BCD decoder (using a 74LS42 IC) and the voltage comparator (using an _LM3914_ bargraph driver), enabling rapid, automatic band switching without the minute-long tuning delays common in other systems. Crucially, the antenna achieves rapid band changes, with typical SWR values centered on common operating segments, such as **3.7 MHz** for 80m SSB. It also discusses modifications for CW operation on 80m and the trade-offs between antenna efficiency and full-range automatic tuning on higher HF bands, where manual adjustment of radiator length is suggested for optimal performance on 15m, 12m, and 10m. The resource includes construction photos and a discussion of cable requirements for reliable operation.

The Vee Beam antenna project presents a versatile solution for hams, enabling operation across all eight High Frequency bands (80m to 10m) with significant gain on 20m to 10m. This easy-to-construct antenna utilizes two long wires at an angle, enhancing directional performance and minimizing ground losses. With a low visual profile, it is discreet and effective for various applications. The design allows for optimal leg lengths and included angles, ensuring robust performance while maintaining simplicity in construction and operation. The V Beam antenna is an aerial that you can use on all eight High Frequency amateur bands (80, 40, 30, 20, 17, 15, 12 and 10m) with an antenna tuner, and which gives significant gain on the five bands from 20 to 10 meters band.

In this experiment the autor is going to explore the use of a 1:64 matching network on the End Fed Long Wire Antenna. Experiment will consist in build a 80-40-20-15-10 meter End Fed Long Wire Antenna with a 1:64 matching network from the documentation available on the internet

An Inverted-L with its long leg sloping to the ground. It will still work very good, even if the horizontal wire has to be sloped diagonally to the ground, as long as you have enough horizontal space to keep it at about a 45 degree angle or more from the pole.

Integrating a **160-meter vertical wire antenna** with an existing 80-meter Yagi system presents unique challenges for Top Band operation. This project outlines the author's experiences with seasonal antenna removal and reinstallation, a necessary task for agricultural land use. It details specific issues encountered, such as incorrect coil sizing and relay configuration problems, providing practical insights into common pitfalls. The article describes the iterative tuning process, comparing **NEC model** predictions with actual on-air performance. It emphasizes the importance of precise measurements and adjustments to achieve optimal resonance and impedance matching. The author shares lessons learned from troubleshooting, including the impact of ground system integrity and feedline considerations. Concluding with an antenna checkup, the resource addresses long-term maintenance aspects, including galvanic corrosion prevention and general upkeep for reliable operation.

WB8LZR details the construction and initial field results of a multi-band vertical wire antenna, designed to complement his existing horizontal loop for improved DX on 80 meters. The antenna utilizes a 67-foot vertical wire, configured as a quarter-wave radiator on 80m, and employs a 1:1 current balun for RF isolation on 80m, 30m, and 17m. For bands like 40m, 20m, and 10m, where the wire acts as a half-wave or full-wave radiator, an additional impedance transforming _unun_ is integrated to manage the significantly higher feedpoint impedance and voltage. The author notes the vertical's performance as a receiving antenna, observing reduced noise compared to his main horizontal loop, particularly on 80m, and even hearing some long-path signals the loop missed. Initial QRP contacts, including a **1-watt** QSO with a _VP2 station_ on 30m, demonstrate its transmit capability. While the radial system is currently rudimentary, the project outlines practical considerations for multi-band vertical deployment and impedance matching.