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A considerably shortened Magnetic Loop antenna with performance of a single conductor text book magnetic loop.

Horn Antennas theory and principles

Antennas are influenced by the effect of the ground and by the type of conductors from which they are constructed. Effects of various types of grounds on a 1.825 MHz horizontal 0.5 wave dipole

How to build Fan-Dipoles by DK7ZB. Experiences with various band combinations. Not all combinations are working properly. If the frequencies are to close together the impedances will lead to a very bad SWR. This happens with the bands 10-12-15m or 15-17-20m.

A review of all possible receiving antennas for top band 160 meters

Sell used low band, mid band and hi band vhf radios and mobile antennas. Used Radio Sales can program these radios to suit your needs.

Three Yagi antennas for the six meters band by 9A7PJT. Include a 4 element yagi, a custom design 4 element, and a 5 element yagi with antennas pictures and design.

How manage and quantify ground loss in vertically-polarized antennas by VE3VN

Homebrewing portable antennas for field day operations

N5KGL interesting article on portable antennas. Greg report his experience on using several types of portable antennas.

Ultra portable and lightweight folding beam antennas based on G3TXQ design

WA1ION article on beverage and ewe antennas

HF VHF UHF antenna ideas to be used for field days. All antennas are quick to set up and take down and offer proven performance and flexibility. Presentation offered by Mahoning Country ARES

The construction principles for open-sleeve elements in antennas

In this article you can find solutions to the problem of keeping your ham radio antennas hidden from the CCR Police

Essentially, a choke balun is designed to 'divorce' your antenna from the feed line. if your feed line is coaxial cable then you don't want it to be part of your antenna. you want to be able to deliver all your power to the radiator itself, i.e. 'the antenna'. a choke balun does this admirably

W3HH wide-band wire antenna Article in French. The W3HH antenna, also known as the Terminated Folded Dipole (T2FD), is a compact, broadband antenna for amateur radio. It operates at an angle of 20 to 40 degrees and covers frequencies from 3 to 30 MHz. The antenna features a total length of one-third of the wavelength at its lowest frequency and is fed using a 1:4 BALUN transformer for impedance matching. A termination resistor around 390 Ω optimizes performance, making it suitable for various amateur radio applications while being easy to construct and install.

SPIDERBEAM.US is the exclusive distributor of Spiderbeam antennas, and online shop for USA & CANADA

Understanding Amateur Radio NVIS Antennas and Propagation

1:49 UNUN using two stacked FT240-43 cores for end fed halfwave antenna. To match the end fed half wave antenna to the coaxial feeder, it is necessary to have a matching network or transmission line transformer.

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

Antennas, Transmission Lines, Tuners - Myths, Mysteries and Qualifiers By Don Wilhelm W3FPR

If you want to design vertical antennas you can find all theory and formulas used to model a vertical aerial calculating capacitance, reactance, building the inductor and calculating resistances. Includes an excel spreadsheet to calculate efficiency.

Custom Metalworks - Tower and Antenna Installation, Removal and Repair. Specialists in the Installation of Rotating Tower Systems, Large Yagi Antennas and Arrays.

Clark county amateur radio club serving sw washington for 75 years! come find out how our local ham club offers programs that cover everything from the history of morse code and call signs to ham radio antennas

A page describing how to home made a custom 9:1 balun for a common portable wire antenna. The author suggest to use 4C65 or FT140-61 toroids instead of the common Amidon T200-2

Homebrewing a vhf bicone antenna with 8 clothes hangers and 4 feet of Sch40 non-metallic rigid conduit

Two different ways to create autotransformer for end fed half wave wire antennas, by using ferrite or air core.

Amateur radio products,wire and yagi antennas, SDR Receivers, upconverters, pre-amplifiers, towers and RTL funcube dongles by CT1FFU

Presentation about Practical Antenna Modeling Using the NEC Codes with examples of HF wire antennas and 4NEC2. How to define and edit the models, Running the simulations, Work some examples, Variables usage, Deal with Feed Lines and ground

Some techniques on homebrewing yagi antennas by VK5AJL

A delta loop antenna for 20 meters band designed with MMana with a tuning system made in a classic stub configuration

Australian manufacturer of HF Communications Antenna Systems for Military, Comercial, Mining & Amateur Radio

On this page you will find information about previous, current and future operations of our contest team, different articles, links and info about contesting, DXing, contests calendar, propagation, antennas, equipment, awards, and much more.

SPX Communication Technologies, operating under the TCI International brand, presents a range of radio frequency (RF) solutions primarily for government, defense, and commercial sectors. The offerings include advanced systems for spectrum monitoring, communications intelligence (COMINT), and high-frequency (HF) and medium-frequency (MF) broadcasting and communication antenna systems. Specific product lines encompass _Blackbird_ COMINT systems, _Scout_ spectrum monitoring receivers, and various antenna arrays designed for robust performance in challenging RF environments. The resource details the capabilities of these systems, such as wideband signal detection, direction finding (DF), and signal analysis, crucial for intelligence gathering and regulatory compliance. It also highlights the engineering behind their antenna designs, which are optimized for specific frequency ranges and operational requirements, including high-power broadcast applications and secure military communications. The information presented emphasizes the integration of hardware and software for comprehensive RF situational awareness. The company's focus on empowering partners to "Command the Spectrum" underscores its commitment to delivering critical tools for signal interception, analysis, and management across diverse operational landscapes.

A Collection of EME Reflector Antennas and YAGI Arrays.

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.

Pictures, design plan and description of a 5 element yagi antenna for the 4 meters band by 9A7PJT

Article provides a guide on how to use 24 GHz band and what to expect, including Active modes, equipment, propagation and antennas for this band in by VE3SMA

The problem originates by improper TXOUT-to-RF timing (RF transmission exists still after a TX-EN prohibition), combined by too long decay of their CW pulses.

The RYMSA Corporation designs, manufactures and distributes a wide range of sophisticated antennas and components for the telecommunications industry supplying technical solutions tailored to the needs of its clients around the world.

An overview of the basics of the horn antenna used in RF microwave applications.

Yaesu FT-100D Active Interface for the Codan 9350 and Comet SB-15 Antennas

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.

160 to 40 meters inverted L antennas projects

Summary, tutorial about the basics of what is a waveguide and the basic waveguide theory.

Antenna gain and directivity explained in this article at radio electronics antenna pages

Antenna design for Horn Antennas

A page dedicated to servicing and building a 10 meter band moxon Antenna

A simple dipole for 40m band feeded with 450-Ohm openwire feedline includes MMANA Gal files to download