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Remotely controlled antenna switch that can switch between 5 antennas

Demonstrates the design and construction of a 9-element Yagi antenna for the **70 cm band** (432 MHz), based on the DK7ZB concept. The resource details EZNEC+ calculations for a single antenna, providing gain, sidelobe suppression, and front-to-back ratio figures. It also presents a comprehensive analysis of stacking two such antennas, including optimal stacking distance (1000 mm) and the resulting performance enhancements for the stacked array, such as an increased gain of 17.03 dBi. The article includes detailed drawings, wire file dimensions in millimeters, and azimuth/elevation plots for both single and stacked configurations. Practical construction steps are documented with original photographs, illustrating element mounting, the **28 Ohm matching system** using two quarter-wave 75 Ohm transmission lines, and the critical N-connector wiring. It also covers the iterative process of fine-tuning the driven element length to achieve a return loss of 20 dB, validating the EZNEC+ simulation results with actual measurements.

Here is a way to ease assembly and balancing of a large antenna. The elements and boom are assembled separately in most cases. Once they are all together set up 2 tripods in the assembly area and put the boom on them.

Choosing the right antenna for you, by Lewis G. McCoy W1ICP

A Low -Power, Distributed Capacitance Twisted Loop , indoor portable HF antenna by Monty Northrup, N5ESE

An 85ft wire fed against a 17ft counterpoise that works well in 80 and 40 meters

435 MHz double quad antenna by F5WN

A discussion of antenna theory by Paul Graham, K9ERG , one of the better antenna explainations out there

Simple, easy to build, low cost, compact, multiband By Robert Wilson, AL7KK

This group has been created to promote discussion relating to the EH Antenna. There should be many with experience with the EH Antenna, so don't be shy about asking questions on construction and efficiency.

A 2,4 GHz 13cm band quadrible qiad antenna with reflector offering a 14dbd gain

Excel spreadsheet that help calculating dimensions of a high efficiency magnetic loop antenna for HF bands. Giving in input the loop perimeter, loop diameter and loop conductor will calculate electric characteristics, bandwidth, and efficiency

This magnetic loop is 78cm diameter, with the smaller Hertz loop for tuning. Feeding is by gamma match.

Antenne Cadre Project by F5NGZ, description by F5TZA in french

Very compact and high efficiency antenna ,very low radiation angle even at low height.

A Bulgarian bazooka antenna project by LZ2ZK

This receive only loop covers a frequency range of about 5 MHz to 22 MHz and is built from readily available parts.

W3EDP multiband wire antenna, an extensive study and analysis of this antenna by W0ESE

A simple quarter-wave length vertical for 40m band using a 12 m spiderpole

This article describes a loop usable from 7 - 21 mHz, using half inch copper tube 3 feet in circumference

Plans and drawings of common amateur radio antennas, like jpoles, copper cactus, super jpole, omnidirectionals and quads

HX-B5i five band HexBeam installation

Anyone attempting to work DX on Top-Band 160 Meters, soon learns of the need for a good receiving antenna. This is a 160 meter 8 element receiving array.

Comparison of several UHF antennas by DF9CY

Homebrew antenna insulators for DK7ZB yagi antennas

A 67 feet long dipole doublet antenna

An old project by I1VCF for a 3 element yagi antenna originally designed for 10/15/20 and extended to 24 and 18 Mhz in Italian

FDLog, a Python-based freeware application, addresses the challenge of synchronized logging for multi-station Field Day operations. It facilitates real-time data sharing across a wireless network, enabling operators to monitor band status and active transmitters at a glance. The software's input system is optimized for minimal keystrokes, streamlining the logging process during intense contest periods. Key features include database synchronization over a wireless network, ensuring all connected computers maintain identical log data. FDLog also incorporates a time synchronization function, designed to keep client programs within a second of a designated master machine, mitigating issues previously encountered with NTP. This internal clock sync can be optionally disabled if not required by the operating setup. Developed initially on Windows 2000, FDLog has demonstrated compatibility with _Linux_ and _macOS_ environments, though some font rendering issues may occur on the latter. The program assists in preparing the ARRL Field Day entry form, simplifying the submission of contest results. User feedback and ARRL rule changes drive ongoing development, with a discussion list available for community support and input.

Progress in Design of Extremely Short Transmitting Antennas Short and still efficient, how is that possible? By Juergen Schaefer, DL7PE author of the MicroVert antenna concept. The MicroVert introduced in this document is an extremely short and hardly visible short-wave antenna with outstanding radiation properties

Rhombic antenna definition and articles by answers.com

One specific challenge in the KazShack, operating Single Operator Two Radios (SO2R), involved sharing a K9AY receive antenna between two transceivers without direct RF connection or manual feedline swapping. The solution, detailed in this project, adapts the **W3LPL RX bandpass filter** design to split 160m and 80m signals, feeding them to separate radio inputs while maintaining isolation. This approach also addresses the issue of strong broadcast band interference from a nearby 50KW WPTF transmitter on 680kc. The construction utilizes T-50-3 toroids and NP0 ceramic capacitors, built in a "dead bug" style on copper clad board. Each band's filter coils are identical and resonated to the desired frequency using an MFJ-259 antenna analyzer. A single DPDT relay, controlled by a remote toggle switch mounted on an aluminum panel, facilitates quick band switching between radios, simplifying low-band operations. While some signal loss is noted, the expected lower noise levels from the receive antenna are anticipated to compensate, potentially reducing the need for constant volume adjustments during toggling between transmit and receive antennas.

Slot antennas explained

Solves antenna matching problem with two phased antennas. Stacked rotary beams are popular. However, connecting two 50 Ohm antennas together presents some problems.

For radio amateurs seeking compact and efficient antenna solutions, particularly for restricted spaces or noise reduction, HF loop antennas present a viable option. This resource compiles several articles from the ARRL, detailing the theory, design considerations, and practical construction of various loop configurations. Topics include small transmitting loops, receiving loops, and multi-band designs, often emphasizing their performance characteristics such as directivity, bandwidth, and impedance matching. The collected articles provide insights into the comparative performance of different loop geometries, such as circular versus square loops, and discuss the impact of conductor size and tuning methods on efficiency. Practical applications are explored, including their use in portable operations, stealth installations, and urban environments where noise mitigation is critical. The content often includes construction diagrams, parts lists, and performance data derived from modeling or field tests, enabling hams to replicate or adapt the designs for their specific operating conditions.

This project produces an inexpensive, multiband, end fed HF antenna matchbox, quick and easy to setup. This project creates a trifilar wound, 9:1 UNUN toroid matching transformer. Handles 100W and need an antenna tuner.

The antenna is a vertical dipole, around which four parasitic elements are forming a circle.

Online helix antenna designer, calculate size of helix antennas online

Fractal antenna for 28 Mhz band by AG1LE

Working priciple of OSJ and jpole anntennas by PY4ZBZ

EB4EQA's Projects GSM1800 moxon square antenna

Many antennas function because of common mode currents, rather than working in spite of them. Two popular examples are CFA and EH antennas. Another recent example, appearing in Antennex's compact antenna articles, is a thick stub "vertical" with no counterpoise.

w4kaz antenna swicth

by Adam M. Farson VA7OJ/AB4OJ

A multiband delta loop antenna made with a random leght wire and a 450 Ohm Balanced line. Antenna tuner is required.

Phased vertical antenna system in french

Slot antenna and complementary dipole

The DL6WU yagi antenna for 23cm band

Antenna experiment - Delta Loop for 7 Mhz band by AG1LE

This is an Excel spreadsheet template to design DL6WU Yagi antennas

Homebrew Wifi antenna test page