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This compact 160m antenna is a half-wave dipole with a vertical section. It requires no radials and has worked well for me.

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 Bruce array is a simple, often-forgotten wire antenna array that is advantageous for 80 and 160 meters, where typical gain antennas are very large. This bi-directional broadside vertical array is only 1\4 lambda high and does not require a ground system. It offers substantially greater SWR bandwidth than the half-square or bobtail curtain. A 4-element Bruce array used by N6LF showed a gain of about 4.6 dB compared to a 1\4 lambda vertical with 8 elevated radials, with a 2:1 SWR bandwidth greater than 400 kHz. The antenna is simple and its dimensions are flexible.

A **90-foot tall** top-loaded vertical antenna for the 160-meter band is detailed, constructed from aluminum irrigation tubing. The design incorporates four sets of four guy wires for structural stability, essential for an antenna of this physical size. This _monoband_ vertical is optimized for low-band operation, providing a robust solution for DXing and contesting on 1.8 MHz. The document includes specific construction methods for assembling the aluminum irrigation tubing sections and securing the guy wires. While a full NEC model is not explicitly provided, the physical dimensions and construction materials are sufficient for replication by experienced builders. The antenna's height and top-loading configuration are critical for achieving efficient radiation on 160 meters, particularly in minimizing ground losses.

A vertical antenna for the top band, made with a 26m fiberglass spiderpole by DJ0IP

This resource details the conversion of an 80m elevated vertical antenna to include 160m operation, focusing on a relay-switched design over a trap-based approach. It presents specific feedpoint impedance values, such as **32 ohms** for 80m and **14 ohms** for 160m, and discusses the challenges of SWR drift encountered with the prior trap system during RTTY contesting. The article thoroughly explains the design choices for elevated radials, referencing _N6LF QEX data_ to debunk common myths regarding radial length and height, demonstrating that non-resonant radials can offer superior current uniformity. The construction section provides practical insights into building the vertical, including guying strategies, material selection from scrap pipe, and weatherproofing the relay assembly. It highlights the use of a common mode choke for the relay switching line, measuring approximately 5K ohms on both 160m and 80m, and details the L/C matching network's role in achieving a 50-ohm match at the end of a 300-foot RG-11 run. The author describes a precise VNA-based radial trimming procedure, achieving resonant values within a 3 KHz range. The content emphasizes the practical application of theoretical antenna principles, particularly concerning the interaction between the vertical element, cap hats, and the matching network. It offers a candid assessment of component selection, such as using junkbox parts and acknowledging the need for future upgrades to static drain resistors. The article serves as a comprehensive case study for advanced antenna builders tackling multi-band vertical designs.

A conversion of a 80m dipole into a 160m vertical antenna

Modeling small 160 meter antennas, with a focus on the vertical H antenna

Design for a quarter wave vertical antenna, for the top band in use at V31YN

SJ2W Contest Station, antenna for the 160 meter is a 39m vertical. This 160m antenna consist of 29m of WIBE tower sections with an insulated base and 10m top tube.

K1JJ presents a compilation of insights regarding vertical radial ground systems, specifically applied to 160m vertical arrays. The resource details 19 distinct observations and recommendations, emphasizing that ground radials primarily reduce ground losses rather than influencing pattern formation. It explains that RF current flows inefficiently through average soil, necessitating copper radials to create a low-resistance path back to the antenna base. The content suggests that **50-60 radials** are generally sufficient to achieve optimal efficiency, with diminishing returns beyond that number, and that radials should be laid on the surface for best performance. The discussion also addresses practical aspects such as wire gauge, installation techniques using 'U' shaped staples, and methods for connecting radials in multi-element arrays. It highlights the importance of radial length, stating that 1/4 wave radials are a crucial minimum, and that for 160m, radials should be at least _100 feet_ long. The resource critically examines the efficacy of elevated radials versus ground radials, noting that while a few elevated radials may suffice for VHF, HF applications, particularly on 160m, require extensive ground radial systems to efficiently collect RF currents in the near field. It also touches on the impact of radial systems on parasitic elements and the significance of symmetrical radial patterns for minimizing losses. Further practical advice includes wire type recommendations, proper soldering and weatherproofing techniques for radial connections, and considerations for integrating steel towers into the ground system. The author shares personal experience with installing 60 quarter-wave and half-wave radials under each of three in-line verticals, expressing satisfaction with the results.

Documents the OC1I and OC6I IOTA DXpeditions to Peru, specifically highlighting operations from SA-098 (Isla La Leona) and SA-076 (Isla Lobos de Afuera). The OC1I team logged over **8000 QSOs** from SA-076, while OC6I made 1400 QSOs from SA-098, despite challenging propagation conditions. The resource details the equipment used, including an _IC-7000_, an IC-706mkIIG, and a TS-440SAT, along with various antennas such as a 160m dipole, FD4, G5RV, and a multi-band vertical for 17m, 20m, 30m, and 40m. The DXpedition dates are specified: OC6I operated from SA-098 between December 28 and December 30, while OC1I was active from SA-076 from January 2 to January 7. Both operations are confirmed as valid for IOTA credit. The page also includes a video link for the OC6I operation and a photo gallery from the DXpedition. Feedback is welcomed, and the webmaster is identified as Bodo Fritsche, DL3OCH.

This antenna is designed for stations having a difficult time putting a decent signal on 160M from small or CC&R d lots. It is a 24.5 ft. vertical antenna, made from three 10 ft. PVC sections bolted together, and half wavelength of antenna wire helically wound around the PVC sections.

The Shoddytenna is a 160 meters band vertical antenna intended for portable use. This antenna takes just 15 minutes to erect on site, can be carried by hand and is ideal for local groundwave work.

The ZS1J/B beacon operates on 28.2025 MHz with 5 Watts output to a half-wave, end-fed vertical antenna, initially installed in 1977 as ZS5VHF near Durban. The 10-meter transmitter is a modified 23-channel CB radio, and the identification keyer uses a diode matrix unit with TTL ICs from the same era. After relocation to Plettenberg Bay in 1993, the beacon has been in continuous service, with additional QRP transmitters later installed for other bands. In 1994, a single-transistor, 80-meter, 0.5-watt QRP transmitter with a half-wave dipole was added on 3586 kHz, followed by a 160-meter, 0.5-watt unit on 1817 kHz. A 30-meter, 0.5-watt transmitter was installed in 1996, operating on 10.124 MHz. In 2002, a 40-meter QRRP beacon on 7029 kHz, with an output of 100 microwatts, achieved DX reports up to 1100 km from ZS6UT in Pretoria. Best DX reports for the 80m and 160m beacons came from 9J2BO.

An essential kite antenna plan for the top band, Antenna has been tested at half wave and quarter wave.

A dual band vertical antenna for 160 and 80 meters band, on a 18m spiderbeam fiberglass pole. This vertical is a good compromise when you want good performance on these two low ham bands and don't have the space to install two seperate antennas.

A vertical antenna for 160 meters band based on the K6MM vertical with some enhancements and modifications on the main capacitance hat

This is a very small vertical 160m antenna that fits in the loft of even my small house. It was built as a way of getting a signal out on 160m for local AM contacts, but the local noise level was far too high to allow it to be used at night for this purpose. However, on WSPR it did a pretty good job with WSPR spots from a very long way across Europe being received when running 2.5W out.

Experimentin wire antennas on top band using several type of aerials. This includes a 40 to 160 meters EndFed Half Wave kite antennas and 160m/80m loaded vertical antenna.

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.

Operating from Banana Island, Sierra Leone (AF-037), the 9L2019 DXpedition by F6KOP and a ten-operator team used the callsign 9LY1JM from January 9-21, 2019. This detailed report covers the logistical challenges, including securing visas and licenses with local assistance from Mark 9L1YXJ and Gregory of Dalton’s Guest House. The team deployed monoband quarter-wave verticals on the beach and two Beverage on Ground (BOG) antennas for Europe/Asia and the USA, operating four stations simultaneously. Technical hurdles encountered included high tides submerging antennas, requiring repositioning, and persistent QRM between closely spaced stations, mitigated by doubling filters. CW signal irregularities at 30-32 WPM were resolved by PC and WINTEST restarts. A significant FT8 logging bug was identified and corrected with on-site software. Despite these issues, the team logged over 4,000 QSOs in the first 24 hours, averaging 5,000 QSOs daily, with a peak of over 6,000 in one day. Propagation varied, with excellent 160m conditions on January 12 yielding over 750 QSOs, and a later four-hour opening pushing the 160m total past 1,600. High bands were challenging due to low solar activity, but mid-bands provided intense pileups and rapid continent-wide contacts. The DXpedition concluded with nearly 50,000 QSOs, including a successful school QSO with Collège Doisneau de Sarralbe (57), managed by F1ULQ and F6KFT.

This study details a reception comparison between vertical and horizontal active loop antennas, specifically two identical _Wellgood active loop antennas_, on various HF bands. The experiment, conducted in a densely populated QRM-prone area, monitored FT8 signals over a 24-hour period using two identical receivers. The methodology involved direct comparison of signal reception across the HF spectrum, aiming to identify performance differences based on antenna orientation. The results indicate that vertical loops demonstrated superior performance on higher bands (10m, 15m, 20m), while horizontal loops excelled on lower bands (30m, 40m, 160m), particularly for receiving long-distance (DX) signals. The horizontal loop's advantage on lower bands is attributed to potentially better low-angle performance and reduced sensitivity to man-made noise, yielding a **2-3 S-unit** improvement on 160m. The study provides practical insights for optimizing antenna placement in challenging urban environments, noting that the horizontal loop consistently showed a **10-15 dB** signal-to-noise ratio improvement on lower bands.

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.

The TY0RU DXpedition to Benin in 2022 achieved over **100,000 QSOs** from Cotonou, IOTA AF-051, operating across 160m through 6m bands using CW, SSB, and FT8 modes. The operation involved a team of 12 operators, including _F5RAV_, _F4WBN_, and _F1TCV_, utilizing multiple stations with transceivers like the Icom IC-7300 and IC-7610, paired with amplifiers and various antennas such as verticals, dipoles, and a 4-square array for 40m. The expedition's log is available on Club Log, supporting OQRS for both direct and bureau QSLs, with F5RAV serving as the QSL manager. The site details the team's travel, setup, and operational challenges, including local conditions and equipment deployment, offering insights into the logistical complexities of activating a rare DXCC entity. Donors are acknowledged, and a photo gallery documents the activity.

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.

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.