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Antennaa matching basics, matching input impedance, reactance vs. SWR, info on inductive matching and UNUN Matching systems. Capacitive Matching Odds & Ends by K0BG

A discone antenna plan and pictures with renderings designe mainly for RTLSDR usage

A simple TRAP-dipole project for 20 and 40m bands includes EZNec simulations

Electronically controlled HF antennas. General coverage. Top features on all ham bands. Very advanced materials and state of the art technology.

Halo antenna plan for the six meters band

A shortened 20m vertical antenna design made with 4Nec2

A triband VHF Yagi antenna for 6 m, 4 m and 2 m with one feed-point by DK7ZB

Christoph petermann's df9cy six element yagi antenna for six meter band

The rhombic antenna is a diamond-shaped antenna, suspended between 4 masts.

A 100Ft wire antenna for the top meter band

A simple antenna tuner for 4m by Tony Hawker G4CJZ

One of the most useful antennas in the repertoire is the Marconi or quarter wave grounded vertical antenna. Its invention made it possible to halve the length of antennas, simplifying communications, especially at HF and below.

DK7ZB- Moxons with Aluminium Tubes, plans for moxon antenna for 6 10 12 15 meters

A dipole for 2m, 4m, 6m band an hamdwritten note for a homemade vhf antenna that can be tuned across the VHF band

German antenna manufacturer for VHF UHF antennas, Quad-antennas, yagi-Antenna, LPDA-Antenna, W-Lan Antennas.

Making your own 2 metre (146 MHz) 5/8th wave whip antenna

The document provides a detailed guide on modifying an inverted-L antenna to include the 160 meters band. This enhancement allows amateur radio operators to utilize the lower frequency effectively, which is crucial for long-distance communication, especially during the night. The inverted-L design is popular due to its compact size and ease of installation, making it suitable for various environments. By adding top band capabilities, operators can engage in DXing and contesting on 160m, expanding their operational range and opportunities. The guide includes practical tips and considerations for construction, ensuring that the antenna maintains its performance across the extended frequency range. It discusses the necessary adjustments and materials required for the modification, along with potential challenges and solutions. Whether you are a seasoned operator or a beginner, this project can enhance your station's capabilities, allowing for more versatile operations and improved signal quality on the 160m band.

A trifilar folded dipole antenna for 80 meters band

A 500-watt mobile antenna project details the conversion of an old 10m hamstick into a highly efficient, multiband "bugstick" for HF operation. The core modification involves replacing the original coil with 25 turns of 6 turns-per-inch, 1.5-inch diameter coil stock, fabricated from #14 wire. This design, intended for a 3-magnet mount on a vehicle cab, achieves resonance on multiple bands by shorting out specific turns on the coil, similar to a **bugcatcher** antenna. Measurements taken with an MFJ-259 analyzer on a GMC pickup show 0 turns shorted for 20 meters (14.2 MHz), 10 turns for 17 meters, 16 turns for 15 meters, 19 turns for 12 meters, and 23 turns for 10 meters. The construction emphasizes using UV-resistant tie-wraps and #14 solid wire with crimp lugs for robust RF connections, bypassing the fiberglass rod for current flow. A bonus section details a 40-meter version, utilizing 48 turns of 8 TPI, 2-inch diameter coil stock.

The Skeleton Slot Antenna Revisited by Bobby Brainwave, N3VGS PDF File.

A magnetic loop antenna using a 28\" bicycle rim for six meter band

A vertical antenna that can cover HF bands using an UN UN and a fishing pole, usage of tuner is requested.

Realization of the YU7EF 6m(6elm) and 4m(7elm) duo band antenna on a 6m boom by OZ1DJJ

KE4UYP project for a top fed 1/4 wave lenght linear loaded vertical for 80m or 160m

The Middle Tennessee Amateur Radio Society is composed of Hams in Middle Tennessee who are dedicated to promoting Amateur Radio, providing public service communications, and having FUN doing so.

Near Vertical Incidence Skywave (NVIS) and the 40 meter Novice Sub-band.

W4KAZ article on antenna switches

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

The industry standard in all antenna products

Calculate EH Antenna, 20m 40 80m. Fotos, Original eh antenna building.

A moxon anetenna plan for 144 MHz

An end-fed halfwave antenna for 20 meters band with balun pictures and description by PD7MAA

N6RK receive 4 square antenna with transformer coupled antennas and true hibrid combiner

A dual band wire antenna project in Italian

How to build the Quickie Pneumatic Antenna Launcher

DIY a sector antenna for de Wifi 2,4GHz ISM band.

A schematic antenna for a 40-80 Morgain dipole antenna with diagram and pictures, article partially in german

An interesting home made project of an L Network Antenna Tuner Project with pictures and schematics by K7SFN

Basic information on the folded dipole antenna

Over 1,000 stations in approximately 60 countries were worked using this modified twin-lead folded dipole, demonstrating its effectiveness with just 4 watts on 20 meters. This design, adapted from an ARRL Handbook concept, eliminates the shorting strap found in traditional folded dipoles, simplifying construction while maintaining performance. It utilizes readily available 300-ohm TV antenna feeder ribbon, making it a cost-effective solution for radio amateurs. The antenna's robust construction allows it to handle up to 100 watts without issues, even without a **balun**. The inclusion of a variable trimmer capacitor at the stub provides flexibility for tuning across different frequencies within a band, a practical feature for operators using transceivers like the Icom 735. Formulas are provided to calculate the precise dimensions for any desired operating frequency, enabling customization for various **HF bands**.

Alan yates vk2zay's ham radio website, homebrew construction, general electronics, high voltage experiments, amateur rocketry, and general geek stuff

An old post by John Doty about effects of noise in longwire antenna.

Schematics of antenna couplers in french

Cheap Antennas for the AMSAT LEO Kent Britain WA5VJB

How could we share the Beverage antennas on more than one station using this homemade remote antenna switch, a project by TK5EP

An Off-center-feed antenna that covers 80, 40, 20, 17, 15, 12, 10, and 6 meters

This article describes a project of asymmetrical hatted vertical dipole, a portable antenna that can be used for field day operations, sota, campings or even for fixed installations. This is a freestanding 20-10m antenna that is really easy to build, easy to tune and relatively easy to carry.

Notes on Axial-Mode Helical Antennas in Amateur Service. Helix Basics, Modeling Issues, and Short Helical Antennas Over Perfect Ground

An homebrew remote antenna switch by vk2zrm

Homebrew a cobwebb antenna for the HF bands. This page describe a cobwebb multiband antenna resonating on 14 18 21 24 and 28 MHz. The cobweb antenna model can be considered a fan dipole, or better, multiple dipoles fed in parallel.