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A project of a bobtail-curtain antenna for 10 MHz

A SQ Loop antenna for 50 MHz, project include pictures and schematic diagram

DIY a Wi-FI Helical Antenna for better performances, a project by PA0HOO i Dutch end English

Loop antenna picture gallery

Alford slot antenna for 1.3 GHz to 2.3 GHz.

A VHF UHF 5+5 elements yagi antenna by CE4WJK

A wifi remote antenna switch that can be controlled from a smartphone app

Building a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

EWE Antenna plan with a 9:1 balun

Accurately determining an antenna's feedpoint impedance is crucial for optimal performance, especially when experimenting with new designs or making adjustments. While SWR meters provide basic information, a full complex impedance measurement reveals the resistive and reactive components, which are essential for proper matching. Modern antenna analyzers, like the _Palstar ZM30_ or MFJ259B, simplify this task, but measurements taken through a transmission line require careful interpretation due to impedance transformation. This resource details a calibration method to precisely account for the effects of the feedline. It explains how a transmission line can significantly alter the measured impedance, illustrating this phenomenon with a Smith Chart example where an 80m antenna's [22 + j6] Ohms feedpoint impedance transforms to [82 + j45] Ohms after a 10m line. The guide demonstrates using a transmission line calculator applet, such as the one by W9CF, to reverse this transformation. It outlines the process of calibrating a specific length of RG174 coax, showing how an initial 26ft estimate was refined to **25.85ft** to accurately predict a known 22 Ohm load, significantly improving accuracy over uncalibrated results.

A method for supporting a balun on a Chushcraft A3S antenna. This allows the balun to be isolated from the boom, thus reducing the effect of introduction of reaction with the balun core.

A DIY project of a WiFi 10 elements Yagi antenna

A 21 MHz Four Square Beam Antenna This popular antenna for the lower bands, can also work well on 15 meters, QST Article

An HF multiband trapped antenna in french

An homemade portable trapped dipole antenna for 40 and 80 meters band with an optional extension for the 20 meters.

A 4 elements handitenna for 70 cm band. This is my version of the K5OE Handitenna. This one is a four Element instead of three, as I had less of a crunch on space than he did. The 1st three elements (Reflector, Driven Element, and Director 1) are the same dimensions as his were.

Antenna experiment a Delta loop antenna for 7 Mhz band

A javascript online calculator for popular wire antennas, from the standard easy to build flat-top dipole, to the inverted V dipole, but also the Quad Loop, and the equilateral delta loop antenna

Notes on W3EDP Antenna by M1KTA

This article describes a simple Inverted L antenna for the HF bands designed to work on 80m, 40m, 30m and 20m

Centre fed half wave dipoles make great, simple and effective antennas for the HF bands. Sometimes however, the centre feed is not ideal. This great project will improve the overall antenna performance.

Adding extra directivity to the Moxon Rectangle for 6m, 4, and 2m

An easy portable VHF antenna to build for ARES - RACES work is the 300 Ohm Twin Lead JPole antenna

Open-Wire/Twinlead Antenna Switch

A 70cm and 2m 6 elements yagi antenna plan based on the IEEE Transactions on Antennas and Propagation

Ferrite rod antenna or aerial, a form of RF antenna that is widely used in RFID and transistor radio applications.

The Folded Dipole is not used much amongst Radio amateurs, probably due to the fact that this antenna uses twice as much wire as a single-wire dipole.

a methodology for connecting multiple LF/MF/HF receivers to a single antenna via readily available and inexpensive 75-ohm TV cable.

Basic of shortwave antennas

Extension to an existing fan dipole originally modeled for 40 20 and 6 meters. This modification will add 80 15 and 10 meter bands.

A moxon rectangle for 50 Mhz band

3 band mobile antenna - 10m full size wave/4 whip - quick tilt-down system for 20 and 15 m loading coil change by IZ7DJR

An end fed 20 meter half wave antenna

This is the Loop Antenna Group to Ask Your Questions, Get Answers and Information about Loop Antennas for improved your Radio Listening and Enjoyment.

VHF UHF diplexer by G8MNY

A homebrew Magmount for 2m antenna

A Slinky-based doublet or loaded vertical QRP antenna tested for 40 meters band

Comparison of 50 and 70 Mhz antennas, commercial and home made projects

This antenna analyzer measures complex impedance over the 1.6 - 33 MHz HF spectrum

Issue 35, October 1992 Six News

Pneumatic Antenna Launchers for sale

An easy to deploy antenna, commonly considered the best solution for portable operations. Thir article includes a simple LC parallel circuit to match the impedance by IW7EHC

A compact antenna for 160 meters, suitable for hams tha want operate top band buh have a limited space

A very basic guide to antennas concept. Explain the usage of dummy load, basic antennas like dipole o j-poles.

A Useful Horizontally Polarised Omni-directional Antenna with Gain for 144 MHz

Helix antenna design and construction details

This article describes the characteristics of the Windom antenna and shows the results of several simulations made with MMANA-GAL, covering models optimized for the 20 m, 40 m and 80 m bands.

A radio's transmitting power can be concentrated along the horizon by use of a GAIN antenna. Although you may still be transmitting with four watts of power, your effective radiated powerwill be greatly increased. This table shows the effects of antenna gain on a transmitter with 4 watts of transmit power.

This article explores the performance of an unloaded elevated vertical, base matching and feed line as a multi-band HF antenna system.

2 Meter Indoor Slim Jim Antennas for Cyclone Season and Other Uses by VK4MDX