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A javascipt online calculator for 2 and 3 element beam antennas. Just input frequency and will diplay element dimensions and spacing. Measurements in Feet and Meters by G4VWL

The Emtech ZM-2 Antenna Tuner is a nifty little portable transmatch for QRP (low power). It utilizes the well-known Z-match circuit, which is especially useful for balanced antennas (like dipoles and loops).

Constructing a linear focus parabolic antenna for WiFi operation involves precise metalwork, as detailed in this project. The author, AB9IL, shares a build that can be completed in a few hours, emphasizing the hands-on process of shaping and assembling metal components. This design aims to provide enhanced signal range for 2.4 GHz wireless networks, a common challenge in many ham shacks and home setups. The project outlines the practical steps required, from initial measurements to the final assembly, including cutting, bending, and bolting various metal parts. While specific gain figures are not provided, the parabolic design inherently offers significant _directional gain_ compared to omnidirectional antennas, making it suitable for point-to-point links or extending network coverage over distances. The construction process focuses on readily available materials and basic shop tools, aligning with the DIY spirit prevalent in amateur radio. This antenna project is presented as a straightforward build, requiring attention to detail in fabrication to achieve optimal performance.

An experimental antenna similar to the TAK spiral antenna was evaluated for SWR response over the frequency range of 7.0 to 7.3 MHz, or the 40-meter band.

RF Choke to prevent hf currents on the feedline. This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

The alternative multi-band solution, covers more bands than a G5RV, light weight, won't damage your trees.

Various tests and designs, with photos of home made EH Antennas,simple and networked, and also sone CAN Antennas.

Theory, Modeling, and Practical Applications By W5JCK, presentation in PDF File. This presentation focuses on Near-Vertical Incidence Skywave (NVIS) antennas, which are crucial for short-range radio communications, particularly in military and emergency contexts. It explores NVIS theory, antenna models, and installation criteria while debunking common myths about reflectors. Key topics include usable frequency bands, optimal installation heights, and the impact of soil quality on performance. The presentation outlines the best bands for daytime and nighttime use, emphasizing the importance of understanding propagation characteristics to enhance communication effectiveness within 200 to 300 miles.

The document details the optimization and construction of the _Maria Maluca_ antenna, a compact 6-band (20m-6m) directional beam. It presents a comparative analysis of shortwave antenna principles, highlighting the efficiency gains achieved by using an open feeder line and tuner as a resonant unit, contrasting this with the losses associated with traps or capacitive loads in multiband antennas. The resource specifically revisits an older South American 2-element design for 10, 15, and 20 meters, applying modern NEC-based software to develop a six-band version. Performance data is meticulously tabulated, showing impedance, free space gain, gain at 12m height, elevation angle, and front-to-back (F/B) ratio for each band from 20m through 6m. For instance, on 15m, the antenna achieves 5.1 dBd free space gain and 13.72 dB F/B ratio. The construction section provides practical guidance on element assembly using aluminum pipes and hose clamps, detailing the use of a heavy-duty glass fiber reinforced polyamide rod for electrical separation and bending strength. It also specifies the use of 450-ohm _Wireman_ line CQ 552 for the transmission line. The document includes diagrams for rod fixing, an air-wound balun, and a vertical elevation diagram for the 15m band, illustrating its DX qualification. It also discusses the antenna's suitability for portable and expedition operations, noting its compact transport dimensions (max 1.50m length, 12 lb weight) and quick assembly time (under 15 minutes). The author, Dipl.Ing. Helmut Oeller, DC6NY, is identified as a source for material kits.

Manufacturer of Fibreglass Whip Antennas, Low and mediun Frequency, HF and VHF Antennas Specialized in the design and manufacturing of a full range of Beacon (MF), AM Broadcasting 540 - 1700 KHz, HF 1.7 to 30 MHz, VHF 30 to 156 MHz and UHF 200 to 500 MHz antennas.

A 144 MHz six element yagi beam antenna plan

How to create a simple but effective half wave dipole, illustrated instrucions on how to build wire antennas

For two purposes a Cross-Yagi can be useful Satellite work or if you need both vertical and horizontal polarization for terrestrial contacts

Kenwood, AOR, CB antennas and accessories.

Splitting an antenna between two receivers or in use as the phasing harness in stacked antennas where there is a need to equally split the power from the transmitter between two antennas

Mizuho Tsushin Co. was a small Japanese manufacturer of QRP radios and kits, shortwave receiver accessories, and AM broadcast band receiver kits and antennas

Transporting Yaesu FT-817 along with antennas and other accessories.

It consists of a group of JavaScript driven web pages that are intended for use as a quick reference for Ham Radio operators or just anyone interested in electronics. Offer calculators for Resistors, capacitors, inductors, power supplies, filters, attenuators and antennas

How slinky loaded beverage antennas works, includes eznec models

Determine the K-Factor used as a multiplier when constructing half-wave antennas.

Online shop based in hong kong offer batteries mic speakers adaptors programming cables earpieces telescopic antennas handheld antennas desktop chargers handheld speakers. Kenwood Icom Yaesu and Alinco dealer

by Chris, G3WOS - July 1992 Six News

Animated quad and yagi comparison. You can see antennas' characteristics behavior in a vertical plane with changing of the height.

Learn basic theory on antennas, and notes on homebrewing efficient shortwave antennas

Overview, summary, tutorial about the dipole antenna or dipole aerial that is widely used on its own and as the basis for other antenna designs.

Notes on homebrewing antennas by Chris G4CYA, from gamma matching, to phasing antennas, splitters and combiners, baluns and measuring techniques.

Nagara Japanese ham radio antenna manufacturer

Testing and comparison of traps and trap antennas

There are lots of good designs for matching transformers for receiving antennas. Make it yourself it's cheap and easy, and very high performance. This is the design used in the TRX-9 transformers.

A 40 ft vertical dipole antenna that can cover HF Bands from 80 to 10 meters winding a dipole in a 12m HD telescoping fiberglass pole

The Charles Gizmotchy high performance horizontal and vertical beam antennas. Two, Six, Ten and eleven meters antennas

An article on TX and RX antennae for the low bands 80 and 160m by EI7BA

This Arduino project decode ICOM CAT frequency information and switch antennas according to preset values. RX and TX antennas can even be different, a project by ON7EQ

This is a 70cm big wheel antenna which is used at DB0FAI beacon

Collection of article and posts on beverage antennas

Members only articles on HF mobile antennas, includes an interesting RV antenna with a 5 bands coverage, and another similar antenna for camper.

An homebrewed dipole antenna for 14MHz

A vertical antenna for the top band, made with a 26m fiberglass spiderpole by DJ0IP

VE7CA experiments on 160 meters band antennas, looking for better performances on reception.

This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

"Low profile antennas for the ""ham"" radio user"

The Homebase10 is a simple to make wire halo antenna for 10m (28MHz) built using parts available from the local DIY store.The resulting antenna is very effective on 10m despite its small size and light weight.

Crossed-Field Antennas and E/H Antennas

A circular waveguide calculator for designing cantennas include source code and windows executable by lincomatic

Manufacturers and distributors of coaxial surge protectors, coaxial switches, insultators, HF fixed wire antennas

G4URH calculations to design your own antennas, ground plane, half wave antennas, Quad Antennas and 5/8 verticals

Sirtel produces a wide range of radio and telecommunications antennas

Excel sheet containing technical comparisons of commercial HF portable antennas compiled by ON4SKY. Includes pictures, manufacturer, db gain, band coverage, F/B ratio, price, weight and dimensions.

Ham Radio Tower Project at N0HR. Includes site plan, escavation, tower construction, HF antennas, grounding and lightning protection, coax and more.

A compact Beam Antenna That Can Be Built At Home. Made with lightweight wooden "X" frame with two folded and linear loaded wire elements. The two elements are approximately a half-wave each.