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This article includes an online calculator for a 3 element Yagi Antenna. The formula and basics theory of Yagi Antenna are also explained with examples.

Receiving rhombic antenna experiments by Jelmer PA5R

Heathkit SB 220 mods, replacing the Zener ZD1, replacing the plate-voltage voltage divider, adding a keying circuit for solid state transceivers

Virtual Serial Ports Emulator for Windows. Virtual Serial Ports Emulator tool (and VSPE API) is free on 32 bit platform and can be used with no charge for any purpose. No registration or activation key is required.

This is a page designed to help the EMCOMM operator thinking of going portable. It will describe a way of having VHF UHF HF voice and digital in one box

KA7OEI article on homebrewing Yagi UDA antennas with practical suggestions and designing notes.

TS-570 series specifications at universalradio

A multi-mode PC to radio interface for PSK, CW, Packet and more digital modes.

One hundred and fifty words per minute (WPM) is a configurable speed setting in this online Morse code translator, which facilitates bidirectional conversion between plain text and **Continuous Wave (CW)**. Users can input text to generate corresponding Morse code, or enter Morse code using dots and dashes to receive a text translation. The tool supports various alphabets, including Latin, Cyrillic, Ukrainian, Hebrew, and Arabic, broadening its utility for international communication. The platform offers multiple output methods for the generated Morse code, including audible playback, visual flashing, and device vibration. Advanced configuration options allow for precise control over the sound's pitch (frequency), volume, and overall speed, including a **Farnsworth speed** setting. This flexibility enables users to customize the learning or communication experience to their specific needs. Additional features include the ability to save the generated Morse code audio as a WAV file and to create shareable links for messages, which can be sent with or without the accompanying text. The interface is entirely web-based, built with HTML5 and JavaScript, ensuring broad compatibility across modern browsers.

A post about the construction and measurements of a Resonant Feedline Dipole cut for the 10M band

Article by Hal Myers K4JHM

With all the wire you have out, you may run into a problem with static buildup on the antennas. This static may try to make its way into your receiver, causing you major problems and damage that can run into a lot of money.

Building EH Antennas at Gemran radio club station house, by Matthias DH4FAW

This graphics-intensive program designs and analyzes active quadrature ("90-degree") networks for use in SSB transmitters and receivers.

The page discusses the concept of a 2-element Parasitic Ground Plane antenna for the 40-meter band. It includes a conversation between amateur radio operators discussing modeling results and design considerations for the antenna. The author shares insights on radial configurations and the impact on antenna efficiency and pattern.

Build the Slim JIM Antenna, a unique VHF Antenna with gain over a J-Pole Jose I. Calderon, DU1ANV

Magnetogram, Dopplergram Intensitygram by Mt. Wilson 150-Foot Tower Data Images

The Windows program for designing and analyzing PI and PI-L networks by Tonne Software

If you're driving around town listening to the buzz and engine whine blues, pick up this free pub and help yourself enjoy the music. Includes troubleshooting techniques and helpful hints.

Refurbishing a Cushcraft A3S, by George Szymanski, DU1GM

Kenwood TS-590S features, accessories, specifications and details

Magnetic Loop Antenna for 20/15m with Remote Tuning by George Szymanski

A Slim Jim Antenna project

CAT (Computer Aided Tuning) connects computers with ham radio. Yaesu FT-890 intercace and ICOM IC-Q7 schematics by DK7IN

Improve the stability of your Yaesu G-250 rotator.

A morse keyer project made on Arduino, inlcudes the main program script by m0xpd

Radio Frequency Interference To/From touch lamps and dimmers

Schematic diagram and description of a magnetic loop antenna that works from 10 to 20 meters band, made from junk

Ham Radio ITU International Callsign Country Prefixes

Mac the Scope is a professional quality signal analyzer, 1/3 octave RTA, signal generator, and more.

Schematic of a homebrew receiver and keying

How to operate Instant Tune and Instant Track or DOS Programs on a last generation computer in french and english by ON6WG F5VIF

Island DXpedition and portable operations, including present, up-and-coming operations, IOTA, NON-IOTA, IOSA, IIA, ILIA, DIB, Lighthouse, and other Island Award Program operations

Cushcraft A3S HF antenna 1:1 balun repair.

This page list schedules for the E10 Spy Number shortwave radio station, commonly believed to be run by mossad.

G4ILO compares popular antennas for 2 metre band handhelds so as to see how much you lose using a small inconspicuous antenna or how much you gain by using a long antenna.

Kenwood TH-D7a TX band modification

Notes about generating RF sweep signals on the Arduino for filter testing, a digital version of the old Wobbulator concept

What makes a good solid-state amp ? by Adam Farson, VA7OJ/AB4OJ, May 2002

This circuit enables fair copy of strong 444 MHz signals, off a local repeater, using a 2m rig and a 1/4λ 70 cm indoor ground plane antenna.

A comparative article on performance differences between Slim Jim antennas versus J-Pole antennas

Theory of the ferrite rod antenna

Some Notes on the Slim Jim Antenna by Dave Coomber M0UXB

An antenna for shortwave radio broadcasting consisting of rows and columns of dipoles, is a high gain directional antenna, designed for medium and long range communications.

Iphone App with list of nearby repeaters in the UK, along with details of input and output frequencies, a map, and a handy bearing arrow for each repeater.

Useful hints & tips on building a 10 and 17 meter Moxon Antenna

This project describes how one USB port can provide all of the signals necessary to operate a transceiver in digital mode from a Windows XP laptop by KG4JJH

The early 20th century saw significant advancements in wireless communication, culminating in the first successful transatlantic radio signal. This historical account details Guglielmo Marconi's pioneering efforts, from his initial experiments with electromagnetic waves to his patented wireless system in 1900. It describes the technical challenges of long-distance radio transmission, particularly the prevailing belief that radio waves would be lost due to the Earth's curvature over vast distances. On December 12, 1901, Marconi established a receiving station in Newfoundland, Canada, utilizing a _coherer_ and balloons to elevate the antenna. Signals, consisting of the Morse code letter "S" (pip-pip-pip), were transmitted from Poldhu, Cornwall, England. The successful reception of these faint but distinct signals across **1,700 miles** confirmed Marconi's theories, marking an epoch in communication history. This achievement demonstrated the viability of global wireless communication, paving the way for future developments in radio technology.

Features, functions, a howto and opinions by Jason Buchanan - N1SU

Hamradio page with pictures and links