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Constructing a portable, high-gain antenna for _AO-40_ satellite operations presents unique challenges, particularly regarding mechanical stability and parabolic accuracy. This resource details the build of a 1.2-meter "brolly dish" antenna, utilizing a non-conducting fiberglass umbrella frame as its foundation. The project outlines a method for achieving a parabolic shape using stressed aluminum fly screen mesh, guided by practical geometry and a temporary dowel template. Key steps include selecting an appropriate umbrella with a suitable f/D ratio (ideally >0.25), removing the original fabric, and precisely cutting and attaching eight segments of fly screen to the struts to form the reflective surface. The construction process, which took approximately five hours for the author, _G6LVB_, resulted in a dish with an f/D of 0.27 (depth=270mm, diameter=1160mm, f=310mm). The article also describes a modification to a _TransSystem AIDC_ feed, incorporating a PCB reflector behind the dipole for easier mounting. Performance tests at a squint angle of 15 deg and a range of 50,000km yielded a signal-to-noise ratio of 33dB on the S2 beacon and 23dB for SSB signals, indicating strong reception. The author notes that the modified umbrella may not close fully without risking surface disfigurement.

Browning Laboratories, Inc. has been a key player in the CB radio community since 1999, focusing on providing accurate information about Browning radio equipment. The website serves as a hub for enthusiasts, offering a wealth of resources including company history, myths and facts, and a collector's guide. It is supported by contributions from Browning enthusiasts and extensive research, ensuring that users have access to the most complete history available. In addition to historical content, the site features links to forums and other resources, fostering a community of CB radio operators and collectors. Whether you're a seasoned DXer or a newcomer to the world of CB radios, Browning Laboratories aims to bring people together through shared knowledge and passion for radio communication. The site is designed for optimal viewing and is regularly updated to maintain its relevance in the ever-evolving landscape of amateur radio.

A Half wave antenna has a high impedance feed point. This can be matched using a 1/4 wave stub matching section and converts the 40m vertical into an L-shaped 20m J-Pole antenna. The 300 ohm feeder used for this purpose must be kept away from the ground.

The page is about the 144 Mhz Dirty Beacon project, a VHF beacon keyer by 9A4QV. It provides technical information, project details, and resources for amateur radio operators interested in beacon keyers. The content is useful for those looking to build or learn about VHF beacon keyers.

Home made keyer with 8 memories, auto spacing, adjustable speed & weighting, separate paddle and key inputs, beacon mode, positive or negative keying, fuse, extremely low power requirements, and a bullet proof housing by AA5TB

External Amplifier Keying from the IC-706 by Bob Wolbert, K6XX

Original article published on February 1992 on 73 Amateur Radio Today about the 2m and 70 cm copper cactus J-pole antenna

Step by step instructions for setting up N1MM Logger to communicate with the TS-590S using the USB connection

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

IK0WRB CW Keyer using a PIC 16F84

These instructions use simple, generally familiar examples of equipment types and are designed to help you find the adjustment that suits you best. If you are looking on how to adjust a morse key, bencher key, paddle or straight morse key, here you will find all instructions.

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.

Processing a single RTTY signal from a transceiver's 3-kHz audio, GRITTY employs _Bayesian statistics_ for superior decoding accuracy compared to traditional trial-and-error methods. This approach not only decodes 5-bit Baudot codes but also calculates the probability of error for each bit, enabling features like color-highlighting unreliable characters and smart squelching based on error probability rather than signal amplitude. This allows decoding of very weak signals while suppressing strong, undecodable interference, resulting in minimal garbage text. The program intelligently analyzes decoded text, comparing similar callsigns bit by bit and merging probabilities using the Bayes formula. This often allows GRITTY to determine the correct callsign and place it on the call stack even when all received copies are corrupt. The same methodology is applied to correct errors in exchange numbers and CQ/DE keywords, and to fix incorrect shift states. GRITTY offers an open API interface, documented in its Help file, for integration with other programs, allowing them to receive decoded data and mouse click events.

A Working analysis of the gamma match problem that gives useful practical results in a article dated April 1969.

Manufacturer of small portable telegraph keys, keyer paddles, and electronic keyer products.

Optimizing DX chasing efforts, this software provides a refined approach to monitoring the DXCluster. It allows operators to configure specific filtering criteria, ensuring that only relevant DX spots are displayed, thereby reducing clutter and focusing attention on desired entities or bands. The application integrates alarm functionalities, notifying the user when a spot matching their predefined parameters appears on the cluster, which is particularly useful for working rare DX or specific band slots. Spot supports both macOS and Windows operating systems, offering a cross-platform solution for a broad user base. Its design emphasizes user control over the displayed information, moving beyond a simple stream of cluster data to an actionable intelligence system for DXers. This client aims to streamline the process of identifying and pursuing DX opportunities. While the software was previously a commercial product, the developer, K3NC, has retired and made registration files for DXBase 2007 available for free, along with a utility to generate registration keys for that specific version. This allows continued use of the DXBase 2007 logging software, though it's important to note the 64-bit OS compatibility modification required for generated registration files.

Cheap Antennas for the AMSAT LEO Kent Britain WA5VJB

The Russian Internet Callbook, hosted at krasnodar.online.ru, offers a specialized lookup service for amateur radio callsigns within the Russian Federation. This online tool is designed to assist DXers and contesters in identifying contact information for Russian stations. The resource functions as a digital callbook, allowing users to search for specific callsigns and retrieve associated data, which is crucial for QSLing and verifying contacts. While the concept is to provide a comprehensive database for Russian amateur radio operators, the current status indicates a configuration issue, as the domain krasnodar.online.ru points to the server but the site itself is not configured. This suggests the service may be inactive or undergoing maintenance, impacting its utility for callsign lookups. The original intent was to serve as a key _DX resource_ for the region.

A free to download and print, paper log sheet useful for portable amateur radio operations, in a PDF file.

Every ham needs an RF power meter. Here is a high performance unit to build at home.

This online article provides a list of individuals who hold or have held amateur radio callsigns, detailing their public recognition. The resource identifies specific callsigns such as **K1JT** (Joe Taylor, Nobel Prize in Physics), **W6OBB** (Art Bell, syndicated radio personality), and **JY1** (King Hussein of Jordan), linking them to their non-amateur achievements. It also notes operational statuses like _Silent Key_ for deceased operators and _lapsed callsign_ for inactive licenses. The article includes information on callsign changes due to vanity callsign programs and provides examples of individuals involved in specific technical areas, such as Percy L. Spencer (**W1GBE**), inventor of the microwave oven, and Jay Kolinsky (**NE2Q**), inventor of electronic sirens. It also references amateur radio involvement in _space missions_ for individuals like Owen Garriot (**W5LFL**) and Helen Sharman (**GB1MIR**). DXZone Focus: Online Article | Famous Hams | Callsign Status | Vanity Callsigns

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.

The document provides a comprehensive overview of baluns, which are devices used to connect balanced loads, like dipole antennas, to unbalanced inputs, such as coaxial cables. It covers various types of baluns, including voltage and current baluns, and their design, construction, and testing. The text discusses the importance of baluns in preventing RF currents on coax shields and their applications in Ham radio setups. It also includes practical advice on selecting and using baluns based on antenna impedance and power ratings, along with detailed performance evaluations and construction tips for different balun configurations.

A re-usable control & computing platform for antenna measurement, PSK31 digital modems, audio filtering, signal source & VFO, memory keyer by AMQRP

The Collins TRC-75 autotune linear amplifier, owned by JF2SVU, is presented with a focus on its internal modifications. This QRO amplifier utilizes three 4CX250 tubes in parallel for its final stage, delivering 1 KW output power. Notably, the amplifier achieves full power with only 100 mW of RF input, a characteristic often associated with Collins designs. The original 400 Hz power supply has been converted for easier shack integration, and the entire RF and power supply sections have been rehoused into a compact, clean enclosure. The control unit, positioned above the amplifier, features three meters for individual vacuum tube IP monitoring and a multi-meter on the right. A dedicated 7 MHz receiver, recently completed, is also part of this integrated system. The autotune functionality means the main amplifier unit only requires connections for power, control, and coaxial cables, simplifying its operation. Key components like the 4CX250 tubes and NF capacitors are visible, along with the gearing mechanism for the final tank circuit. A timer and relay system manages high-voltage delay and cooling fan off-delay, although the cooling fan's airflow is noted as somewhat insufficient. A central volume control, which experienced a contact issue, is also highlighted.

Custom iambic paddles by N3ZN

If you have space constraint at your QTH for a HF antenna, you can try contructing this HF magnetic loop antenna for 40-20 meters bands

A museum of thousands of telegraph keys, radios, microphones, enigma cipher machines, and scientific instruments.

Arduino automatic CW Keyer for amateur radio

Need to interface both a TNC and the computer soundcard? This is a ICOM 756PRO ACC1 audio/keying/FSK interface by WA0SXV

VoiceKeyDeluxe (VKD) will convert your sound card into a powerful and versatile digital voice keyer for contest or EME operations by N7QJP

At the moment the most used program is UA1AAF. It is an excellent program written by Boris, UA1AAF, to handle ARI International DX Contest. It can simulate K1EA or N6TR workings; it will be possible to connect the RTX to the computer using a standard interface in such a way as to transmit directly in CW from the keyboard; most of the controls are like K1EA's CT and N6TR's TR ; on line help provides almost all the information necessary for using the program. Is possible to insert QSO after the contest. An appropriate utility in included for conversion in ADIF format. The program is very small and therefore works without any problems on any IBM compatible computer with DOS 3.3 and over or Windows 95/98.

A sourge arrestor for PL 259 connectors. A voltage surge arrestor to limit the voltage that may come back down the wire or coax after there has been static build up

This is the ham radio station of VK4HF near Brisbane Australia which is available for Ham Radio Holidays.

The Olivia transmission system is constructed of two layers: the lower, modulation layer is an (almost) classical Multi-Frequency Shift Keying (MFSK) and the higher layer is a Forward Error-Correcting (FEC) code based on Walsh functions.

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

Ham Radio Kits, morse keyers, Morse code voltmeter / DC switch / battery saver

PSK31 is a digital communications mode which is intended for live keyboard-to-keyboard conversations, similar to radioteletype. Its data rate is 31.25 bauds (about 50 word-per-minute), and its narrow bandwidth (approximately 60 Hz at -26 dB) reduces its susceptibility to noise.

Personal Web Site of UX7CQ. Information about Ukraine. Old military radios collection. CW Straight Keys.

A Tribute to Morse telegraphy and resource for wire and wireless telegraph historians and key collectors

Key your transmitter from the tone output of a Morse Code generator program

Manufacturer of led digital clocks, digital timers, countdown clocks, electronic kits, audio switches, binary clock, telegraph keys, and cool gadgets.

Sound Byte is a voice keyer for contests as well as general ham radio use. Windows and Mac, commercial by Black Cat Systems

DK7JC Morse Key Collection

Part 2 - Ten-Tec Jupiter CW copying and keyboard transmit

Service manual in PDF Format for the Yaesu FT-7800 transceiver

An end fed 20 meter half wave antenna

For macOS users engaged in amateur radio operations, a robust logging solution is essential for tracking QSOs, managing contest entries, and handling QSLs. RUMLog addresses these needs by providing a fully featured logbook program designed specifically for the Apple ecosystem. It integrates capabilities such as transceiver control for popular Icom, Elecraft, Yaesu, and Kenwood rigs, CW keyer interfacing, and real-time DX cluster monitoring. The software also includes mapping functions, callsign checking, and extensive import/export options for various log data formats. RUMLog's design supports both general logging and specialized contest operations, offering tools for efficient entry and submission. Its QSL handling and printing utilities streamline the confirmation process, a critical aspect for award pursuits like _DXCC_. The program's ability to interface with a wide array of transceivers via _Hamlib_ or proprietary protocols ensures broad compatibility, allowing operators to leverage its features across different station configurations. The free availability of RUMLog makes it an accessible option for macOS-based hams seeking a powerful logging utility.

Collection of telegraph keys homebrew antenna projects links to radio software

DIY voice keyer for your next ham radio contest. An interesting homebew voice keyer project by ON7EQ