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A comprehensive guide to receive Weather Satellites signals in wefax mode

G3TPW CobWebb Antenna for the 14, 18, 21, 24 and 28 MHz Bands

This article describes the 144MHz horizontally polarised antenna at VK1OD in November 2008. The antenna uses two identical four element arrays that were constructed around 1970

Manufacturer of telecom structures and related accessories

A MRF141G 3-175MHz Broadband Power Amplifier DL4MEA 02/1998

by Ken Neubeck WB2AMU

The HF ham bands can be mysterious. Some work at night, some during the day. Some seem to be good for long distance contacts while some are better for nearby contacts. Even worse, they change tremendously from hour to hour and day to day. An overview on operating on HF amateur radio bands

Sometimes amateurs like to home-brew their power supplies instead of purchasing one off the shelf at any of the major ham radio retail dealers.

List of latest published Weather Fax world wide schedule including frequencies and modes.

Tuning the Solarcon Antron A-99 antenna for 20 meters band

Lowering an NVIS or N.V.I.S. antenna very close to the ground enhances NVIS operation

Free windows comprehensive tool for Finite Impulse Response (FIR) filter design

Convert a PC power supply for your ham radio transceiver

AN Wireless is a manufacturer and distributor of Self Supporting Tower Systems for Wireless Communications, Wireless Internet, Wireless Networking, Microwave, Paging, Broadcast, Two-Way Radio and Amateur Radio.

Detroit Fire Department Radio Feed

Whether we are tuning up homebrew equipment, checking antenna VSWR, adjusting a linear amplifier, or just monitoring output power during a contest, almost all aspects of ham operation can use a power meter. Paul Wade W1GHZ

Schematic of a regulated 0-24v 2A Power Supply

HF Weather Fax lets you receive marine weather radiofascimile transmissions on your iPad, iPhone and iPod Touch. Just connect it to a shortwave radio tune in a weather fax frequency, and watch the images come in.

Increase TS 480 PEP power level

An Eprom Eraser with UV-Ray for 27Cxx Eprom (and similar, common in TNC) with a timer

Huge amount of relevant information you should know before building a tower

Website dedicated to Coastal Radio Stations, includes frequency lists for memdium frequencies maritime stations

A simple accurate power splitter for the 70cm uplink to Oscar 13

Technical and modification information on Astron Power Supplies compiled from a number of different sources by Mike Morris WA6ILQ

Building a PEP Power circuit for all analogue watt-meter

A shortened 20m vertical antenna design made with 4Nec2

HAMIC, is a program designed to simplify a number of calculations commonly used by HAMs. It is designed for the HAM radio hobbyist, but may be useful to others as well. HAMIC has a simple to use, but powerful graphical interface that allows solving simple circuits such as resistors in series or parallel, or more complex circuits such as L networks or T networks. As well, other calculations such as SWR and reactance conversions are supported. Windows shareware.

Converting A PC Power supply for Amateur Equipment

BCL DX news compiled by Wolfgang Büschel

Two types of multi-functional Home-brew 6/8Amps - 20 Ampere variable power supplies by ON6MU

Robert Norgards KL7FM's, notes on upgrading the Heathkit SB-200

This article documents the modification of 2 types of Hewlett Packard switching power supplies to enable their use as power sources for ham radio equipment

G3WZT design for a bi-polar 600W Linear Power Amplifier for the 6M band.

Excellent slides explaining radio and radiowaves generation basics

DX Finder presents a real-time DX cluster service tailored for amateur radio operators engaged in DX chasing and contesting. The platform aggregates DX spots, Reverse Beacon Network (RBN) data, and PSK Reporter information, displaying current activity across various amateur bands. It provides a centralized interface for monitoring propagation conditions and identifying rare DX entities, aiding operators in making timely contacts. The service integrates multiple data streams to offer a comprehensive view of global amateur radio activity. Users can access real-time spotting data, which includes callsigns, frequencies, modes, and signal reports, facilitating efficient station operation. The inclusion of RBN and PSK Reporter data enhances situational awareness, allowing operators to assess band openings and signal paths more effectively. DX Finder supports both web and Telnet access, catering to different operational preferences. It also features a dedicated JOTA cluster, specifically designed to support the Jamboree On The Air event.

Codec2, an open-source speech codec, targets low bit rate voice communication, specifically designed for digital radio applications operating within constrained bandwidths. The project focuses on achieving intelligible speech quality at data rates around 2400 bits per second, a critical parameter for efficient spectrum utilization in amateur radio. Its development addresses the need for robust voice transmission over channels where higher bit rate codecs would be impractical or inefficient. The resource details the technical specifications and implementation aspects of Codec2, including its underlying algorithms and performance characteristics. It provides insights into how the codec processes speech to achieve its low bit rate, outlining the various coding schemes and their impact on voice fidelity and error resilience. The information presented allows radio amateurs and developers to understand the codec's operational principles and its suitability for integration into custom digital communication systems. Applications for Codec2 extend to digital voice modes on HF and VHF bands, enabling more users to share limited spectrum resources. The project's open-source nature facilitates community contributions and widespread adoption, fostering innovation in digital amateur radio. It represents a significant effort to provide a freely available, high-performance speech coding solution for the amateur radio community.

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.

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

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

Despite the title referencing the callsigns 3C5J and MW0BRO, the content of this resource focuses entirely on the _Cleddau Computer Clinic_, an IT services company operating in Pembrokeshire since 1999. The site outlines a broad range of computer-related services, including custom-built new PCs starting from £399, sales of used systems, and comprehensive repair and upgrade options for existing units. Services extend to anti-virus and spyware removal, system installation, and broadband connection setup. The clinic also provides tuition for hardware and software applications, website design, and video to DVD transfer. They specialize in both fixed and wireless network solutions, enabling clients to share files and broadband connections efficiently. Repairs can be conducted either in their workshop or at the client's home or office, offering flexibility. For situations where on-site repair is not feasible, the Cleddau Computer Clinic offers a temporary replacement computer service. This includes transferring essential data to minimize disruption, a practical approach for local businesses and individuals in areas like Pembroke, Milford Haven, and Haverfordwest.

The circuit is based on two AD8307 log amplifiers, which are connected to the forward and reflected ports on a directional coupler

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.

DIY kits a 70W SSB linear Power Amplifier for YAESU FT-817 KX3 running HF 80m-10m bands

An RF power Amplifier for HF bands with 3 GI-7B tubes by CT1FMS

A simple RF power amplifier initially designed for 40 meter band can work on 10 15 20 40 80 meters

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

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

Broadcast Tower Specialist. Offering Manufacturing, Engineering, Erection and Tower Extension Services. Self Supporting or Guyed Towers.

Baluns / Ununs design and acceptable power

This article describes a simple device to generate Roger Beep tones.