u dipole

528 links - and 1 categories

20m Coil-Shortened Dipole - Build a low-cost 20m shower rod dipole antenna
[ Hits: 104 | Votes: 0 | Rating: 0 ]

Portable Coaxial Dipole Flower Pot Antenna - A homebrew 2m 144.2 MHz vertical 1/2 wave Coaxial Dipole antenna project for your home QTH, SOTA, portable field operations/WICEN exercises or the emergency 2m Go-box. Elsewhere in amateur radio circles this antenna is known as a 2m Flower Pot Antenna
[ Hits: 105 | Votes: 1 | Rating: 8 ]

SAFARI 40-30m vertical Antenna - Roach pole vertical antenna for 40 and 30 meters band featuring good performance on short skips contacts compared to wire dipole
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30m Half -Size Rotary Dipole - A rotary dipole antenna for 30 meters band. Each arm is about 12.5 ft and is constructed from telescoping fibreglass flag/fishing poles and short lengths of aluminium tubing. Two short lengths of glass-fibre rod were used to insulate the arms from the supporting hardware.
[ Hits: 198 | Votes: 0 | Rating: 0 ]
Shortened 30m Dipole - This article describes the construction of a 9,50 m long dipole for the 30 m band (10.1 MHz to 10.15 MHz). It was designed to be mounted ca. 6 m above ground inside an attic. The calculations were performed by OE1MEW
[ Hits: 124 | Votes: 1 | Rating: 1 ]

40m Wire Antennas Comparison - On the field comparison among C-Pole antenna, an EFHW vertical antenna and an Inverter V dipole antenna. Test is done using two identical WSPRLite beacons that transmit with 200mW on the WSPR frequency and analyzing spotted results.
[ Hits: 172 | Votes: 1 | Rating: 3 ]

Enhancing Performance with a Cage Dipole for Six Meter Band - Explore the design and testing of a cage dipole antenna for 6 meters. Through innovative construction, witness a remarkable 77% increase in bandwidth and improved impedance characteristics.
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Extended Double Zepp NVIS Antenna Calculator - Extended Double Zepp measurements for all ham bands, and online calculator. The antenna is constructed much like an ordinary Dipole antenna but with 5/8 Wavelength Elements matched with an added Impedance Matching Section of balanced feed line
[ Hits: 124 | Votes: 3 | Rating: 7 ]
Online LInked Dipole Designer - The page for designing linked dipole antennas allows users to swiftly create a versatile multi-band antenna suitable for portable applications in outdoor settings, such as in the field or on mountain tops.
[ Hits: 99 | Votes: 0 | Rating: 0 ]

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 ]

160-80-40 Metre Trapped V-Dipole - 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.
[ Hits: 109 | Votes: 0 | Rating: 0 ]
Bent-end dipole antennas - Discussion about laterally bent-end dipoles. Bent by percentage of length and fine-tuned by angling the bent ends.
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Make your own 40/80 Dipole - Make your own dipole for 40 and 80 meters band, assembling standard product parts like 40 meter traps, the 1:1 balun and insulators
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Moxon Mania - Building the Ultimate 4-Band Moxon Antenna - The article details the design and construction of a four-band Moxon beam by a radio amateur. The beam, mounted atop a rooftop tower, aimed for gain over a dipole on 20 meters, cost under $500, and included additional bands. The design features fiberglass spreaders, four bands (20/15/10/6 meters), and a single feedpoint. The construction involved computer modeling, NEC source code, and specific dimensions. The article outlines the assembly, materials, and tuning process, including in-situ adjustments for optimal performance. Despite initial challenges, the beam improved signal strength and facilitated contacts on multiple bands, marking it as the best HF antenna the author has owned.
[ Hits: 96 | Votes: 0 | Rating: 0 ]

Open-Folded W8JK Antenna for HF - Originally designed by John Kraus, W8JK in about 1940, this antenna has some interesting properties. The W8JK antenna is 2 (Two) centre-fed double-dipole fed by a pair of anti-phase signals. Small size, simple antenna, offer nice performance but need a tuner. Tested in this project from 30m to 6m bands
[ Hits: 141 | Votes: 1 | Rating: 3 ]

Angle of OCF L-Dipole Antennas - This page is a discussion about impedance matching by Off Center Fed dipoles in the Wide L-form. When a vertical or horizontal dipole is bent into a 90 degree L-form, the impedance drops about half.
[ Hits: 76 | Votes: 0 | Rating: 0 ]

The Infamous Attic Dipole - An attic wire antenna with several modifications during the time. Began as a simple coax fed doublet antenna, and upgraded to a multi-band hf fan dipole, till the G5RV all deployed in an attic.
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Variations on a Dipole - Antenna patterns are all about interference. Presentation on wire antennas for HF bands. Dipoles, horizontal and vertical dipoles, effects of ground on radiation patterns, multi-band wires antennas. Knowing what you should expect from the radiation patterns for waves on your wires will help you choose what will work best for your needs. The principles of interference can lend insight into what to expect from a wire antenna.
[ Hits: 98 | Votes: 0 | Rating: 0 ]

Cloverleaf Antenna - Cloverleaf antenna is a circular polarized antenna which is way better than the cheap dipole antenna that comes with video transmitters and receivers. The Cloverleaf is a closed loop antenna which the signal and ground wires are connected. The cloverleaf antenna has 3 loops at 120 degree apart, and they are titled at 45 degree to horizontal plane.
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Receiving NOAA Weather Satellite Images - Receiving NOAA weather satellite images using a Raspberry PI with a RTL dongle and a Turnstile crossed dipole automatically.
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