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TNC-Pi is a special version of TNC-X designed to interface directly with the Raspberry Pi computer. It can connect to the Pi either via the Pi serial port, or via the I2C protocol.

iPhone Software to practice taking your Ham Radio Exam

Rail Radio Communication Feeds broadcasted from all over the United States and beyond.

A project to homebrew a Lightning Detector

This is another alternative home-brew center connector for a dipole. The parts used are common PVC accesories found at the home supply store.

A workbench instrument capable of testing transistors, diodes, FETs, usefull constructing QRP circuitry.

How to repair a FT1000MP front end, damaged from too much neighbouring RF during contesting

Hi-Z Antennas offers specialized high-impedance receiving systems, primarily focusing on phased vertical arrays for HF reception. Their product line includes preamplifiers designed for shortened vertical antennas, featuring optimized 15dB gain and array-matched characteristics. These components are engineered to enhance weak signal reception and improve signal-to-noise ratio across the HF spectrum. The company provides controllers for managing multiple vertical elements in a phased array configuration, enabling directional reception patterns. These systems are particularly effective for mitigating local noise and interference, a common challenge in urban and suburban operating environments. Specific offerings include solutions for 160-meter and 80-meter bands, addressing the unique requirements of low-band DXing. Technical details often reference components like the 2N3866 transistor in preamp designs and discuss concepts such as out-of-band attenuation. The focus remains on optimizing receiving antenna performance through impedance matching and active amplification, rather than transmit capabilities.

Articles about Amateur Radio, own writings and translations: history, DXpeditions, contesting and DXing ethics, Codes of Conduct, Suggestions for Pile-ups, Suggestions for Contesters, the most wanted DXCC entities.

Double T Bar Vertical antenna are vertical antenna with cross bars on the top and bottom. These crossbars provide capacitance loading thus reducing the size of the antenna

Long Beach Los Angeles county live scanner feed

Over 45 years of dedicated work by Robert Sherwood, NC0B, culminated in a wealth of technical insights, particularly concerning **receiver performance** and the intricacies of transceiver design. The site provides access to numerous presentations from events like Dayton Contest University and W4DXCC, covering topics such as optimizing rig performance, the evolution of lab testing, and the impact of roofing filters on transmitted IMD and receiver characteristics. These resources offer detailed analyses and practical advice for serious operators and contesters. While product manufacturing, including the SE-3 MK IV synchronous detector and various Drake R-4C accessories like roofing filters and cooling kits, has ceased, the legacy of technical documentation remains. The site details specific products like the Icom IC-781 and R-9000, and offers insights into 455 kHz mechanical and crystal filters, along with DSP protection strategies. Crucially, the site features extensive receiver test data, allowing radio amateurs to compare the performance of various transceivers. This data, often presented in white papers and slide shows, includes detailed measurements and explanations of key performance metrics, serving as a valuable reference for understanding and selecting high-performance HF gear.

Ham Radio Class Exam question pool effective 7/01/2010 thru 6/30/2014

Construct a compact, 20 meter rotatable dipole antenna of durable weather worthy components supported at a single point obviating the need for multiple supports and multiple support ropes crossing the yard.

Based on a simple project based on a 2 elements Yagi for 20m band, and then becomed a triband yagi with a open-sleeve feed system

A web site dedicated to collecting and restoring antique crosley tube raidos. pictures and descriptions of antique crosley tube radios from the twentiew, thirties, forties, and fifties. radio advertising from the twenties, thirties, forties, and fifties. tube box art. links to many antique radio related sites.

XLT Communications two way radio accessory manufacturer, microphones, headsets, belt clips, earpieces, radio cases

A mail list for those interested in the new Amateur Radio MFSK modes.

This antenna article is geared towards new Hams and antenna builders looking for a very inexpensive 6 band antenna that can be efficiently fed with 50 ohm coax without a tune

A complete EmComm portable station article on eham.net by K9RFZ

Radio Singapore International

A QRP association of amateur radio operators based in Sardinia Island Italy

Tubes, military manuals and surpluss

European Telecommunications Satellite Organization

W0IPL article on NVIS Antenna

The use of dummy load is mandatory for off-air adjustment of the transmitters. Build one.

Skin effect and proximity effect on making coils with stranded wire. An interesting comparison on making coils.

Computers, TV's, and Switching Systems can cause noises to your receiver

Cheap hand held Spectrum Analyzer

Sporadic-E clouds location and estimated MUF real time map

The Pecker is a software application that emulates an existing hardware amplifier tuning aid operated in SSB mode as apposed to CW or AM. As such no carrier is used by G7EIX

Ultra-lightweight 2m Yagi for SOTA

Alternate means of raising your tower with readily available boat and engine hoists. Examples of working tower hoists with links to manufacturers.

Codec2 is an open source low bit rate speech codec designed for communications quality speech at 2400 bit/s and below. Applications include low bandwidth HF/VHF digital radio and VOIP trunking.

Since they were first described by the French mathematician Benoit Mandelbrot in the mid-1970s, repeating geometric figures known as fractals have fascinated computer scientists, mathematicians and graphic artists.

Adam Brown's Blog from Latitude 80.19 South Longitude 81.16 West

A portable USB SO2R box made with Arduino

An Arduino uno based project to control an MFJ 998 antenna tuner via Icom CI-V interface by VE1ZAC

This circuit came out of some work done for two antenna analysers

May 2015 Radcom Article on common-mode chokes that can be used for control cables, phone lines, but mostly on typical HF antenna systems. This article explain what common mode chokes does, why you meay need one, properties common mode chokes should have, how to build and measure performances.

A nice post on Make: on homebrewing a multiband antenna for amateur radio portable operations

MyHamPlace is a online amateur radio shop based in China dealer for Heilsound, Elecraft, MFJ, Yaesu , Kenwood and other popula ham radio brands

tk3 is open source software designed for the ICOM IC-R3 receiver. Though tk3 is intended chiefly for Linux, MacOS X, and BSD users, it will work on Microsoft Windows too.

The FieldComm Association, based in Central Virginia, operates as a specialized amateur radio club with a primary interest in emergency communications. Members engage in various technical aspects of radio, including digital modes, QRP operations, and DXing. The association provides a platform for hams to develop skills in field deployment and reliable communication under challenging conditions, often leveraging modern digital protocols. This organization's activities support the practical application of amateur radio for public service, emphasizing readiness and operational proficiency. Members collaborate on projects and share knowledge, fostering expertise in areas like portable station setup and efficient data transmission. The focus on emergency communications distinguishes its operational priorities from general interest clubs, aligning its efforts with community preparedness.

Kentucky farmer invents wireless telephone! But was it radio? Facts and folklore about Nathan Stubblefield by Bob Lochte.

Topband and DX recordings and sound files on 160 meters band

Presents the Amateur Radio on the International Space Station (ARISS) program, a global educational initiative facilitating direct communication between students and astronauts via amateur radio. It outlines the operational framework for scheduled school contacts, detailing the technical requirements for ground stations and the typical Q&A format used during these events. The program utilizes VHF/UHF frequencies for voice and packet radio communications, enabling students to engage with crew members aboard the ISS. ARISS supports various educational objectives, promoting STEM fields through hands-on radio experience. The resource provides information on how schools can apply for contacts, the selection process, and preparation guidelines. It also covers the history of amateur radio in space, including past missions and the evolution of equipment used on the ISS. Regular updates on contact opportunities, operational status, and technical specifications for ARISS hardware are provided.

Building the MFJ Cub QRP transceiver kit for 20 meters band by G4ILO

Australia's largest range of Electronic Kits & Components In Stock for the Radio Experimenter, ATV, microwaves, HF Band pass filters

Amateur Radio pictures to add Interest to your Website. Jpeg, GIF and Animated GIF files available to download.