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Dual band vhf uhf dipole antenna by DL7JV

A half-sized Hentenna designed for unique performance in compact spaces. Initially built in 2003 for monitoring a local 146.97 MHz repeater from a basement shop, the antenna proved highly effective, operating at just 200mW. In 2005, it was adapted for use in a challenging river-bottom location, delivering reliable performance on a 2-meter band with 5W. Despite its compact size, the Forktenna demonstrated excellent results compared to a full-sized Hentenna, making it an intriguing option for many hams.

A multiband wire antenna with a twinlead feedline that can be easily tuned in several bands, witha 33 ft per leg you can have a 40 to 10 meters band coverage

An Active antenna designed for VLF and shortwave radio reception. A small antenna capable of excellent performances on low bands, made on a copper plate and introductio to active antennas.

An homebrew crossed Yagi antenna for two meters band based on DK72B design with pictures, detailed description and tricks by Barry Zarucki M0DGQ

Different band dipoles can be put together with a single feed, learn how by W8HDU

The Classic Multiband Dipole Antenna QST article. The open-wire feed line dipole antenna is easy to install and offers surprising performance on several bands. You can install it in almost any configuration; it does not have to be strung in the traditional horizontal flat top

This is a 200 Watt PEP step up transformer for end fed full and half wave antennas without radials, designed as a 200 Watt PEP

The antenna is an inexpensive, multiband, end fed HF antenna. It has a matching network consisting of a toroid core and an antenna lead of 30

Operating a ZS6BKW antenna often involves understanding its lineage from the _G5RV_ design, with specific modifications by ZS6BKW to optimize performance on several bands. Through computational analysis and field measurements, the antenna's dimensions were refined to allow operation on 10, 12, 17, 20, and 40 meters without an antenna tuner. For 80, 30, and 15 meters, a tuner is necessary, though efficiency on 30 and 15 meters is noted as not particularly high. The physical configuration consists of two 13.755-meter radiating elements fed by a 12.20-meter section of 450-ohm ladder line. Tuning the antenna on the 20-meter band is critical, and any deviation in the ladder line's characteristic impedance necessitates recalculating the element lengths. The design is also referenced in the 12th edition of _Rothammel's Antennenbuch_, page 219. Proper common mode current suppression is crucial at the transition from ladder line to coaxial cable. This can be achieved with a common mode choke, such as several turns of coax wound into a coil or over a ferrite toroid like an Amidon T130. While a 1:1 balun is an option, it may introduce issues.

Sharing information on Topband Homebrew Antennas, Base & Mobile

This project will enable you to build a monoband long wire inverted vee with 3/4 wave length sides that will have a bit of gain

A compact Quad Antenna for the HF Bands by GM0ONX

A 90-foot vertical antenna constructed from **aluminum irrigation tubing** is detailed, focusing on its innovative raising and lowering mechanism. The resource describes a **45-foot ginpole** system, allowing a single operator to erect or lower the antenna in minutes. It covers the mechanical design, including the pivot base, insulated joints for the tubing sections, and guy wire attachment points. The antenna consists of two 30-foot sections of 4-inch tubing and one 30-foot section of 2-inch tubing, stacked with the smaller diameter at the top. The electrical design incorporates PVC "condulet" boxes at the 30-foot and 60-foot points, housing relays to change the effective height for multi-band operation on 160, 80, 40, and 30 meters. Ferrite rod inductive chokes are used for DC control and to tune out gap capacitance. The antenna is fed with 1000 feet of open wire line, connected to a matching transformer comprising stacked toroids and a coaxial/toroidal balun. Grounding is achieved with a 3x3 foot grid of 16-gauge tinned copper wires with soldered crossovers.

A simple vertical antenna for 70 cm band

PA5DD version of the dual band yagi antenna for 50 and 70 Mhz

Dutch Antenna and Tower Manufacturers from Slimline Square Triangular Round Towers. Antennas production include Yagi Monoband/Dipole/HF Quad /50MHz and 70MHz Yagi-Quad, VHF-UHF yagi-Quad and Comby antennas VHF/UHF/SHF

A full size delta loop antenna for top band by PA3FUN

An cheap, easy to construct and not too visible antenna for the low bands

A compact multiband wire antenna suitable for portable operations.

A copper pipe Hentenna for 144 MHz. The Hentenna, a compact, high-gain loop antenna developed in Japan in the 1970s, offers approximately 5.1 dBd gain, comparable to a three-element Yagi. Adapted for 2 meters, it is crafted from copper pipe for simplicity, affordability, and broadband performance. Requiring no feed-point tuning, its construction involves soldering standard copper fittings. Installation demands non-conductive materials to minimize signal disruption. Versatile for vertical or horizontal polarization, it is ideal for FM, repeater, SSB, or CW applications. This design emphasizes practicality and performance for amateur radio enthusiasts

This antenna consists of 4 resonate dipoles made from 12 insulated copper electrical wire. The dipoles are resonate on the following bands: 6 meters, 10 meters, 12 meters and 17 meters.

A wip antenna for 6 meters band by JA1HWO

Build your own multi-band mobile ham antenna with a Hamstick

A delta loop antenna for 6 meters band with SWR diagram , construction plan and some pictures by IZ8EWD in Italian

An efficient 2 meter antenna disguised as a TV Satellite dish. This vertically polarized horizontal slot antenna, cut into the reflector of a TV dish, might be the ultimate stealth antenna.

A monoband antenna with large bandwidth in French

All bands HF mobile antennas manufacturer

This resource details the conversion of an 80m elevated vertical antenna to include 160m operation, focusing on a relay-switched design over a trap-based approach. It presents specific feedpoint impedance values, such as **32 ohms** for 80m and **14 ohms** for 160m, and discusses the challenges of SWR drift encountered with the prior trap system during RTTY contesting. The article thoroughly explains the design choices for elevated radials, referencing _N6LF QEX data_ to debunk common myths regarding radial length and height, demonstrating that non-resonant radials can offer superior current uniformity. The construction section provides practical insights into building the vertical, including guying strategies, material selection from scrap pipe, and weatherproofing the relay assembly. It highlights the use of a common mode choke for the relay switching line, measuring approximately 5K ohms on both 160m and 80m, and details the L/C matching network's role in achieving a 50-ohm match at the end of a 300-foot RG-11 run. The author describes a precise VNA-based radial trimming procedure, achieving resonant values within a 3 KHz range. The content emphasizes the practical application of theoretical antenna principles, particularly concerning the interaction between the vertical element, cap hats, and the matching network. It offers a candid assessment of component selection, such as using junkbox parts and acknowledging the need for future upgrades to static drain resistors. The article serves as a comprehensive case study for advanced antenna builders tackling multi-band vertical designs.

G3TXQ pages focuses on understanding the HexBeam antennas. Basics, dimensions, multi band issues, antenna modeling.

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.

VA3EXT 5 element beam antenna for 6 meters band

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

W3DZZ trapped multi-band antenna, exposed in this practical wireless article

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

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

A multiband dipole antenna that can work on 15 20 and 40 meters band made with common materials

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 vertical antenna consist of a 18 meters telescopic pole and allow operations from 160 to 30 meters band, project by Daniel Zimmerman N3OX

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.

HX-B5i five band HexBeam installation

A 67 feet long dipole doublet antenna

Planning and modelling Delta Loop antennas for all the ham radio HF bands include calculated wire lengths at each mid-band

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.

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.

A project for a homemade multiband Hexbeam antenna for 10, 12, 15, 17 and 20 meters

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.

A simple delta loop antenna antenna for the six metre amateur radio band

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.