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A multi band antenna for HF band capable to operate from 10 to 80 meters band depending on wire lenght loaded with a small inductance neat the feed end.

Horizontal polarized omni directional 50MHz Antenna. This antenna is intented to use in a contest station as a second system beside the stacked yagi beam system. An omnidirectional systeem can be an advantage when it comes to short openings on wich the operator must react quickly.

Article about the microstrip antenna, which is also commonly referred to as the patch antenna.

Notes on how to properly install a Mini Whip receiving antenna in an noisy urban environment.

Ham radio VHF UHF antennas, aircraft, scanners, marine vhf antennas

No exotic claims are made for this antenna. Author just tried a few WSPR experiments on 40 meters and was surprised with the results. What appears below may inspire you to try something equally off-the-wall, to see what happens.

RSGB article for beginners. How to build a dipole antenna, construction tips and correct setup of inverted-ve dipole antennas

Considerations on using attic antennas for dx anc contesting operations.

Article based on ROHN engineering specification that will guide on proper guying heights and guy lengths when guying ham radio antenna masts. It will help you determine ahead of time the proper length of guy wires and the distance from the base of the mast to the anchor points

Article on 50 Mhz Yagi Antennas stacking by OH1ZAA/NN0Y

An home made remote antenna tuner project that with a 6 meter random wire and two radials of about the same length, can tune from 40 to 10 meters without any issue.

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.

A free Labview antenna calculator program. This interesting calculator for small loop antennas can be ran on most recent Windows versions using the Labview runtime.

This antenna was conceived mainly for high-speed digital transmission via satellite. The antenna is made of two full waves loops , mounted at right angles to each other. Then coupled together, 90 degrees out of phase over a horizontal circular reflector. With this configuration the antenna is omni directional and circularly polarized.

A folded dipole is an antenna, with two conductors connected on both sides, and folded to form a cylindrical closed shape, to which feed is given at the center.

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

This simple antenna was installed on the attic. Antenna was matched with help an Automatic ATU in 40, 30, 20, 17, 15, 12 and 10 meter amateur Bands. The Antenna worked satisfactory on the above mentioned bands.

A trap antenna dipole covering two differen bands made reusing an old 160/80m inverted vee antenna.

Antenna may be made practically from any wire (strand, solid) having a reasonable diameter 0.5 2.0 mm (24- 12 AWG). Antenna may be installed at any balcony of 3 to 6 meter length.

When a broadcast antenna is to be placed on top of a building, there are special problems of feeding and grounding. The radiator is usually electrically short, that is, much less than one-quarter wavelength high.

A 3.2m EME dish project that provides a better performance on 1296 MHz (10+dB sun noise vs. 6dB with my 432 array) and an even better performance on 2304 MHz

The two dipoles are parallel with a distance of 12 cm and are also fed in parallel. The total length of the 4 m dipole is 208 cm and the 6 m dipole is 280 cm.

Founded in 1990, Nearson, Inc. has been providing our customers with exceptional value with the products and services we offer. VHF, UHF mobile radios, Cellular, PCS equipments as well as ISM band wireless data and WLAN applications.

Hairspray-can EH Antennas for shortwave and online programs. Small magnetic (H) antennas (Loops) have a good efficiency for the upper bands (20/15/10 meter band) and also in contrast to E-antenna a defined radiation direction.

HF Skeleton Slot An antenna system with a difference.

Measuring noise fiugre on the W2IMU horn and the dual-dipole-feed

An article describing basic concepts of antenna radiation, and in particular directional antennas like Yagi antennas or Quad antennas and how they determine the direction or signals.

An home made antenna switch with a Dummy Load selector. If you forget the radio is connected to the open or grounded side of the switch and you try to transmit, it is very easy to damage the finals of your transceiver.

The wire antenna described in this page provides much stronger signal strength while staying within the concept of a dummy load antenna.

A loop antenna for 80 and 40 meters band, the main loop is based by a crossed line using aluminium strip lines. The main loop diameter is 150 cm.

Why build antennas out of copper and not aluminum or stainless steel. Selecting the best metals for antennas evaluating the conductivity factor.

You can shorten a vertical antenna by using a loading coil. This online calculator tells you how the amout of inductance your loading coil will need to have.

A modified Hairpin antenna for a wider bandwidth an mounted on a grounded metalic mast

Benefits of stacking two HF antennas vertically

Have you measured the SWR at the antenna?

The antenna described in this article is for 50 MHz, but the design can be scaled for any band, including VHF, UHF, or even the higher HF bands. The antenna is nothing more than a square loop of wire, approximately 30" (or ~76cm) per side. The loop is fed in the middle of one side, and the opposite side to the feed point has a gap in it.

This is a standard calculation method that can help you while tuning dipole antennas, by adjusting wire lengths. This method can be used also when you need to add lenght to your wires, and can be additionally used to quarter waves vertical antennas

A 70 cm yagi antenna design by YU7EF includes tables with antenna elements dimension and spacing. This UHF Yagi antenna plan provides a maximum gain of 17.93 db

This is a simple 160 meters antenna, a short loaded inverted L. The linear lenght is 20 meters, with the loading coil at 5 meters from the feedpoint.

A fand dipole antenna home made for the 7,14,50 MHz. This article descbribes how to homebrew the antenna, hot to setup and some SWR measurements.

A home made magnetic loop for HF Bands. This small and compact loop is designed to support small power transmissions on HF bands, from 7 MHz to 21 MHz

NEC models are used to explore the GR5V and ZS8BKW optimizations. A third optimization is also rediscovered. The effect of fixed lengths of 75 ohm coax are explored. A link to the NEC model is provided.

Article descrive the different types including coax and open-wire feeder and waveguide.

The OCFD Off-Center-Fed Dipole Antenna is an excellent multiband antenna that is relatively simple to construct, yet gets quite decent performance.

This DIY vertical multi-band Windom antenna offers a practical and effective solution for amateur radio enthusiasts seeking a versatile and compact antenna for HF communications. Its simplicity of construction, multi-band capability, and favorable performance make it a valuable addition to any radio shack. The article provides detailed instructions on constructing the antenna and balun, along with diagrams and component specifications. Field tests demonstrated successful contacts with stations across Europe and North America on 14, 18, and 28 MHz. The antenna exhibited comparable performance to a W3DZZ dipole and outperformed a Cobweb antenna on 18 MHz. Low noise levels were observed, effectively suppressing background noise.

Active Receiving Antennas, designed for reception of shortwave, mediumwave and longwave signals and VHF/UHF signals

Modifying an MFJ-259B Antenna Analyzer to operate on 630 meters

An experimental antenna for HF reception. It consists of a single loop element mounted on the ground. It is stealthy, small, and quiet. EZ-NEC plots and on-air test results are included.

The collinear antenna, or Marconi-Franklin antenna, is an omnidirectional, high-gain antenna composed of in-phase half-wave dipoles aligned vertically. By using quarter-wave transmission line segments, it maximizes gain at a low horizon angle, outperforming a half-wave dipole. Adding segments increases gain but narrows bandwidth. A popular DIY version, the CoCo antenna, uses half-wave coaxial cable segments connected by non-radiating transmission lines. Built with stable velocity factor cables, a matching quarter-wave sleeve balun, and ferrite rings for attenuation, the antenna achieves performance comparable to commercial models.

A comparison of commercial 4m verticals by by Ian Hogan G6TGO