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How to build the Quickie Pneumatic Antenna Launcher

A dual band wire antenna project in Italian

Welcome to the farm, where the primary crop is big towers and antennas.

50 MHz meteor scatter offers a unique opportunity for amateur radio operators to make long-distance QSOs, even when the band appears dead. Meteor scatter involves reflecting radio waves off the ionized trails left by meteors burning up in the upper atmosphere, typically around 105 km high. These trails can facilitate contacts over distances up to approximately 2,300 km. The technique is particularly effective during meteor showers, which increase the number of meteors and thus the chances of successful QSOs. However, random meteors can also be used to achieve contacts, especially on the 50 MHz band, where the longer reflection time compared to 144 MHz makes it easier to work meteor scatter. Operators should be prepared to make QSOs in short bursts, often lasting only a few seconds. The IARU Region 1 meteor scatter procedure recommends using 2.5-minute periods for telegraphy and 1-minute periods for SSB, though shorter periods can be arranged. For 50 MHz SSB, 15-second timing is often used to maximize the chances of completing a contact. The procedure involves specific timing for transmissions based on direction and requires both operators to confirm receipt of callsigns and reports to complete a QSO. Understanding the geometry of meteor scatter, including the optimal radiation angles and the concept of 'hot spots,' is crucial. These hot spots are areas where reflections are most likely to occur, influenced by the Earth's rotation and the path of the meteors. Proper antenna setup, including elevation control and beam direction, can significantly enhance the chances of successful meteor scatter QSOs.

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

A lightweight inverted vee antenna that can be supported by a 10 metre long fiberglass squid pole. The antenna is designed to cover 10, 15, 20, 40 and 80 m bands.

CB radios and antennas are available online at WeAreCB.com. Everything from police scanners to ham radio antennas in one convenient location.

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

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

Contest, Antennas, Rotating Towers, Rotors, Guywires, CoaxHardlines, Specs and more

January 1955 QST article by W5DQV about constructing a Cubical Quad antenna for 14MHz PDF File

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**.

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.

Choosing a vertical antenna. Buying guide to amateur radio HF vertical antennas by Bencher inc

Calculate online, ERP in dB and dBi given PWR Frequency Coax lenght and type and antenna type

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

Cheap Antennas for the AMSAT LEO Kent Britain WA5VJB

A magnetic loop antenna for 7 Mhz by ZL1BJQ

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

How to build your own beverage antenna for 80-160 meters band by K5ZD

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

A balun is a MUST for dipoles or similar antennas when they are feed with coaxial cables. Many hams connect the center conductor of the coaxial cable to one side of the dipole, and the shield to the other. Wrong!

High End isopole VHF & UHF antennas for Amateur, Commercial and Military applications.

This article presents a method of controlling preamps, antenna switching and polarization switching remotely without the use of control cables.

cocoaNEC 2.0 is an opensource Mac OS X application intended primarily for the design and modeling of antennas by Kok Chen, W7AY

A J-pole antenna plan made using a half inch copper tubing

Telescopic antenna towers, fixed antenna towers, stacked and sigle section antenna towers, trailer towers, cargo trailers accessories

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

How to build a super AM antenna, These plans have been used by many people, with good results.

An interesting article by K3DAV comparing the COMET CHA250B to other HF multiband vertical antennas

Double Bazooka Antenna, a simple coax based and broad band antenna you can easily build

A project for a home made 5 element yagi-uda antenna for 2 meters, covering 144-148 MHz band by N1BMX

James Miller G3RUH article on amsat site

Inverted Vee antenna for 40m with simulation data by DF9CY

Backpacking, boating or mountaintopping ? Invest your time and pack this novel directional gain antenna on your next expedition

This 4m Slim Jim Antenna is cheap and easy to build yet it greatly out performs the more usual dipole due to its low angle of radiation. An SWR of 1:1 is obtainable across the 4m ham radio FM band with a simple adjustment.

Nowdays lots of people are putting up antennas to either beam in different directions at the same time or just to stack them and get a lower angle of radiation. Use this stackmatch to match you array.

A helpful guide to building your own beverage-type low noise receiving antenna for broadband use. Easy, do-it-yourself suggestions to optimize directional performance, even if you lack a farm to put it on.

Original drawing and design of a 4 and 7 elements yagi antenna for 50 Mhz

An home made Z-Match antenna tuner unit that cover all HF bands between 10 and 160 meters

Article published on Practical Wireless about the W3DZZ multiband trapped dipole antenna made available by GM0ONX

An engineering oriented organization specializing in the design and manufacture of high performance parabolic antennas, 3dB high power RF couplers, Antenna power splitters, directional RF couplers and more items for RF transmission from HF through Microwave frequencies.

Group with thousand of memebers focused on NVIS antenna

Videos of AO-51 operations. Randy K7AGE has produced a number of practical and useful videos including good info on a minimal antenna setup for AO-51 reception.

SimSmith is a highly interactive, real time Smith chart graphing program. Circuits are constructed using drag-n-drop. Load files can be imported from the EZNEC and CocoaNEC antenna simulation software and from the AIM4170 and miniVNApro antenna analyzers. Circuits and load files can be of any size. Key Features: SimSmith is one of the few Smith chart packages which models transmission line losses. SimSmith also allows the description of circuit elements using algebraic equations. SimSmith has only one screen and allows the screen to be resized to increase workspace or readability.