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Speaker Wire Delta Loop Antenna for 20M - The antenna I built was inspired by a portable delta loop designed by Doug DeMaw, W1FB. Given that I constrained myself to a 50-foot roll of speak wire, I scaled my antenna for the 20M band. Using the formula, 1005 divided by the frequency in megahertz, I calculated a total length of 71 feet (21.6 meters) for the center of the 20M band.
[ Hits: 127 | Votes: 0 | Rating: 0 ]

Delta Loop DX Antenna for 40 meters band - A monoband delta loop antenna for the 7 MHz. This vertically polarized DX Antenna is a full wavelength sngle side antenna and has a total length of 42.3 meters (137,1 inch) Can be easily setup with a flag pole or fishing pole as center top mast. For optimal performance lower side should be at 2 meter above the ground. This antenna offers a low radiation angle and 1 DB Gain.
[ Hits: 433 | Votes: 3 | Rating: 6.33 ]

A shortened 40 meter rotary dipole - The antenna build into this project is made from 2 fishing poles on a fiberglass pole in the center.
[ Hits: 1215 | Votes: 4 | Rating: 4.75 ]

End-fed 6-meter Zepp - A half-wave antenna can be end-fed or center-fed. An end-fed half-wave antenna may offer mechanical and construction advantages over a center-fed antenna. The radiation pattern for an end-fed half-wave antenna is no different than a center-fed half-wave antenna.
[ Hits: 174 | Votes: 2 | Rating: 9 ]

QRP Balun: A DIY Project - DIY project of a QRP Balun. Using a high permeability ferrite rod and an old B&W dipole center insulator, he constructs a choke type balun for QRP use. The balun aims to create as much inductance as possible at HF, offering a high impedance to common mode currents
[ Hits: 59 | Votes: 0 | Rating: 0 ]

DIY CobWebb Antenna - A DIY guide to build your own compact multiband HF antenna based on the G3TXQ version using a 1:4 balun. This article includes the full part list and instructions to assembly, including the center plate.
[ Hits: 1005 | Votes: 6 | Rating: 7.5 ]

Bent-end dipole antennas - Discussion about laterally bent-end dipoles. Bent by percentage of length and fine-tuned by angling the bent ends.
[ Hits: 123 | Votes: 0 | Rating: 0 ]

End Fed Half Wave Antenna Coupler - A home made end-fed half-wave antenna coupler with antenna lenght calculator and counterpoise calculator based on center frequency. Includes pictures and drawings along to antenna homebrewing instructions with a home made on air wound transformer
[ Hits: 282 | Votes: 0 | Rating: 0 ]
End Fed Half-Wave Antennas - An interesting article on end fed half-wave wire antennas with a couple of original experiments. Author illustrate the role of the QRP matchbox, and a 40/20 meter antenna with a center stub making it a large bandwidth antenna for 40 and 20. Includes also an 80/40 end fed with the typical coil to make it available on 80 merts band.
[ Hits: 288 | Votes: 2 | Rating: 10 ]

Magnetic Loop for the 2m band - Such kind of omnidirectional antenna gives the possibility to be QRV with horizontal polarisation, as commonly used for the CW and SSB section of the 2m band. This actual design shows a 1.3:1 bandwidth of about 150kHz, centered to 144.200MHz.
[ Hits: 573 | Votes: 1 | Rating: 10 ]

The Off-Center-Fed Dipole Antenna - The OCFD Off-Center-Fed Dipole Antenna is an excellent multiband antenna that is relatively simple to construct, yet gets quite decent performance.
[ Hits: 328 | Votes: 2 | Rating: 9 ]
Homebrew an OCF Off-Center Fed Dipole Antenna - 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.
[ Hits: 198 | Votes: 3 | Rating: 6.67 ]

Portable Vertical Antenna - A home made portable vertical antenna, that with a single 1/4 wave counterpoise wire is possible to achieve less than 1.5:1 SWR on 40, 30, and 20 meter bands. It is basically a center load, shortened ground plain vertical antenna.
[ Hits: 362 | Votes: 0 | Rating: 0 ]

40m center loaded vertical antenna - A 5 metre center loaded vertical for 40m combined with a 4 wire ground plane.
[ Hits: 297 | Votes: 0 | Rating: 0 ]

DXCenter DX Cluster - Online world map with live updates from the DX Cluster network, displaying new spots on the maps as they appear. Filtering options are available including bands, source continent and dx continent.
[ Hits: 352 | Votes: 2 | Rating: 5.5 ]

Middlesex Amateur Radio Society - An ARRL Special Service Club. Meets every Tuesday at Portland Senior Center, 7 Waverly Ave., Portland, CT 06480
[ Hits: 158 | Votes: 1 | Rating: 10 ]

N7BYU Brigham Young University Amateur Radio Club - Brigham Young University Amateur Radio Club (BYUARC) was founded in 1949 and has been headquartered in several places on BYU campus over the years, finally coming to its permanent location in the Wilkinson Student Center in the 1970s.
[ Hits: 177 | Votes: 0 | Rating: 0 ]

APRS Direct - Realtime APRS tracking data - APRS Direct is a website that brings you global real-time APRS tracking and weather data (including CWOP). Our goal is to bring you a fast and easy-to-use map with the latest APRS activity.
[ Hits: 278 | Votes: 6 | Rating: 8.5 ]

Sunspot Index and Long-term Solar Observations - The Solar Influences Data analysis Center SIDC is a department of the Royal Observatory of Belgium and its mission is to preserve, develop and diffuse the knowledge of the long-term variations of solar activity.
[ Hits: 141 | Votes: 0 | Rating: 0 ]

RF Impedance Matching Calculator - Calculates the network to match a line to a specific complex load. This online tool calculates the matching network necessary to terminate a line of the specified characteristic impedence Zo in a specific complex load impedence RL + jXL at a specified frequency.
[ Hits: 194 | Votes: 1 | Rating: 10 ]