Search results

Build a space efficient trapped dipole antenna for 40-80-160 meter bands using RG-58 and PVC pipe. The document provides a brief guide on building a compact dipole antenna appropriate for the 40, 80, and 160-meter amateur radio bands. It explains the materials, building processes, and tuning methods required to provide best performance while preserving space. The paper also discusses theoretical elements of dipole antennas, such as impedance matching and feedline selection.

A multiband 80-40-20-15 meters dipole wire antenna that can be extended to cover 160 meters too.

Demonstrates the construction and performance of an updated ZS6BKW multiband dipole, a variant of the _G5RV_ antenna, specifically designed for HF operation. The article details a real-world installation using 13.5m copper wire elements and 12.2m of 450 Ohm ladder line, configured as a sloping inverted-V with the apex at 10m and ends at 4m above ground. It covers the critical aspect of impedance matching, incorporating an 8-turn choke balun at the feedline transition to RG-58U coax to mitigate RF common mode current. Measurements confirm favorable SWR readings below **1.3:1** on 7.1 MHz, 14.11 MHz, 18.06 MHz, and 24.8 MHz, indicating effective resonance across 40m, 20m, 17m, and 12m bands. The installation also shows usable SWR dips on 3.55 MHz (5:1), 29.02 MHz (2:1), and 50.84 MHz (3:1), extending its utility to 80m, 10m, and 6m with an antenna tuning unit. Initial on-air results report clear reception of stations over **5000km** away, validating its DX potential.

Live DX spots are presented through a _web cluster_ interface, utilizing both a world map and a Google Maps display for visualizing amateur radio propagation. The system provides real-time spotting data, enabling operators to track active stations globally. Users can observe current band conditions and station activity, which is crucial for optimizing contact strategies across various amateur bands. The platform's utility extends to contest operations and general DXing, offering a visual representation of where stations are being heard. While the primary function is DX spotting, the site also includes technical articles, such as instructions for interlocking two Flex Radios for single-transmitter compliance in contests, and a guide for constructing a simple **5KW** 1:1 balun for **160m/80m** dipoles using RG400 cable. This combination of live data and practical technical content supports both operational awareness and station improvement.

The X80 multi-band HF vertical antenna, a commercial iteration of the Rybakov design, exhibits a physical length of 5.5 meters, or approximately 18 feet, and is constructed from aluminum tubing. It operates as a non-resonant vertical, requiring an external antenna tuner for impedance matching across its intended operating frequencies. The antenna's design incorporates a 1:4 UNUN at its base, facilitating a nominal 50-ohm feed point impedance for the coaxial cable. Performance observations indicate effective operation on 40 meters, 20 meters, 15 meters, and 10 meters, with reduced efficiency on 80 meters and 160 meters due to its relatively short electrical length for these lower bands. Comparative analysis with a G5RV dipole and a half-wave end-fed antenna reveals the X80 offers a lower take-off angle, beneficial for DX contacts, particularly on the higher HF bands. Field tests conducted with an Icom IC-706MKIIG transceiver and an LDG AT-100ProII autotuner demonstrate the X80's ability to achieve acceptable SWR across 80m through 10m. The antenna's compact footprint and ease of deployment make it suitable for restricted spaces or portable operations, though its performance on 80 meters is noted as a compromise compared to full-size resonant antennas.

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.

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.

This magnetic loop DIY site is ment to be an introduction into making DX high quality magnetic loop antennas that will beat any dipole

This type of antenna is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It’s a dipole fed off center with a 4:1 balun at the offset feed point. The antenna shown covers 80, 40, 20 and 10 meters. The formula can also be used to adjust the overall length to cover more or fewer bands and the resulting overall length. 160-10m, 80-10m or 40-10 meters depending on your available space. Other bands will require a tuner.

A 3 band dipole antenna for 40-80-160 meter bands, It's made with easily available materials and is designed for inverted V mounting. The antenna is shortened for these bands, but still manages to make contacts in 80m and 160m with stations in Canada and the USA. The construction details are provided, including the dimensions of the antenna elements and the traps. The antenna is easy to build and provides good performance in all three bands. In Italian.

A 60-foot available space, for example, might necessitate a shortened multiband dipole array to cover 80, 40, and 15 meters effectively. This resource details the construction of such an antenna, combining full-size and coil-loaded dipoles on a single feedline. It addresses the common challenge of fitting multiple HF bands into restricted physical footprints, providing practical guidance for hams with smaller backyards or portable operations. The core of the offering is an interactive calculator that determines required loading coil inductance and dipole lengths for various amateur bands from 160m to 10m. Users input their available space, and the tool provides dimensions, coil turns, and an efficiency rating (Good or Fair) based on the antenna's electrical length relative to a quarter-wavelength. It also suggests suitable _PVC_ pipe diameters for coil forms. The article further illustrates a center feed-point assembly using an 18-inch section of 2-inch _PVC_ pipe, detailing eye-bolt spacing and coaxial connector installation. It emphasizes the importance of adequate spacing between parallel dipoles and offers customization options for the feed-point, including the addition of a _Balun_ for improved feedline isolation.

A Trapped dipole inverted V antenna for lower HF Bands. Construction details are for temporary installation. Permanent installations will require additional ruggedising and waterproofing however the basic electronics concepts remain the same. This project includes SWR plots for the three bands and pictures details of the homemade traps.

From March 2 to March 11, 2018, a Norwegian team operated as Z2LA from Zimbabwe, focusing on 160m through 10m bands using SSB and CW modes. The operation, described as "holiday style," aimed to provide contacts for DXers worldwide seeking a rare DXCC entity. Key equipment included a SUNSDR PRO II, an Elecraft KX3, and an Icom 706 MK2G as a spare radio, supported by two Juma 1000 amplifiers for robust signal output across the bands. Antenna systems were tailored for multi-band operation, featuring an Inv L for 160m and 80m, sloping dipoles for 30m/40m, and a _Hexbeam_ from SP7IDX Technology covering 20m to 10m. For improved reception, the team deployed a SAL 30, two reversible BEV antennas from remoteqth.com, and a BOG from K1FZ, enhancing their ability to hear weak signals. QSL information directs operators to Clublog for log search and M0OXO Charles for OQRS, explicitly requesting no bureau cards. The team comprised LA7THA Rune, LA7WCA Arne, and LA9VPA Thor, successfully making numerous contacts and contributing to the DX community's pursuit of _Zimbabwe_ as a DXCC entity.

Learn how an experienced ham radio operator rebuilt his trap dipole antenna for 30, 40, and 80 meters after a storm damage. Discover the process of upgrading to a short trap dipole for 40, 80, and 160 meters using double-wound traps made from RG-58 coax. Follow along for construction details and tips on building this unique classi.