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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.

Approximately 24 minutes of recorded audio from Flame Christian Community Radio on 1521 kHz was logged on January 4, 2014, demonstrating the pursuit of distant broadcast stations. This resource focuses on the hobby of DXing, primarily targeting the Mediumwave (AM) band and the 2-6 MHz shortwave Tropical Bands, along with VHF FM. It details how factors like solar activity, time of day, and seasonal weather patterns significantly influence radio propagation, enabling reception of signals from hundreds or even thousands of miles away. The site includes a collection of DX logs, such as _Sporadic E_ reception of FM stations from Algeria, Spain, and Portugal in May 2020, and _Radio New Zealand_ on 15720 kHz. It also features comprehensive UK RDS listings, information on _MW Carrier Monitoring_ of European and trans-Atlantic AM carriers, and reviews of equipment like the _Sangean ATS909_ portable radio. Historical news entries document significant events like the closure of CBC's 50 kW CBA transmitter on 1070 kHz and RTE's 567 kHz MW channel.

DarkIce is a live audio streamer. It records audio from an audio interface (e.g. sound card), encodes it and sends it to a streaming server. Works on Linux and MacOSX

Francisc Grunberg, YO4PX, shares his insights and translations on various amateur radio topics through his blog. Content includes historical perspectives on ham radio, detailed accounts of _DXpeditions_, and discussions on ethical operating practices for DXing and contesting. The site also offers practical advice, such as suggestions for navigating pile-ups and improving contesting strategies. The blog delves into the intricacies of the hobby, providing guidance for operators aiming to improve their skills and understanding. It covers subjects like Codes of Conduct for amateur radio and lists the **most wanted DXCC entities**, offering a valuable resource for those pursuing awards. Francisc's contributions reflect his extensive experience, providing a unique perspective on the amateur radio landscape.

MorseExpert 1.15 decodes Morse Code audio to text, leveraging algorithms from CW Skimmer for optimal performance on weak, fading signals amidst interference on amateur radio bands. It processes audio from the device's built-in microphone or an external radio receiver via cable, optionally highlighting Ham callsigns and keywords. The application features a waterfall display with a bandwidth of 200-1200 Hz, decodes frequencies between 300-1100 Hz, and supports keying speeds from 12-45 WPM with automatic CW pitch detection. Recent updates include support for Android 15, edge-to-edge mode, improved stability, and a pause decoding button. A premium version offers an ad-free experience and user-selected text colors. Users can switch between General Text mode and Ham Radio QSO mode, which enhances word segmentation and highlights callsigns. The app also includes a frequency lock mode, text selection capabilities for copying, sharing, or saving decoded text, and provides guidance on reducing acoustic echo and constructing an audio attenuator for optimal radio interfacing.

The **Nilex Morse Tutor** is an HTML5 web application designed to teach Morse code reception, adapting to user proficiency by adding new characters as readiness is detected. It prioritizes practice on less familiar letters, numbers, symbols, words, and phrases, while minimizing repetition of already mastered elements. The program offers multiple learning orders, including "Q7ZG..." (Ward/Jim's), "KMRS..." (PU5EPX/Koch), "KMUR..." (lcwo.net), "AENT..." (CWops CW Academy), "TEAN..." (Stephen C Phillips), "ANET..." (Vic VE3YT), and "ETI5..." (Ham Whisperer), alongside an alphabetical option. Users can customize the learning experience by enabling or disabling automatic progression, and selecting specific content categories such as numbers, symbols, words, phrases, QSO bits, Ham Radio Bands, X+Y=Z math, and units. Audio settings are adjustable for volume, speed (WPM), tone frequency, and keyshape/keying envelope, allowing for a personalized auditory environment. The interface provides visual feedback with blue bars indicating practice emphasis and gray bars for reserved characters, with clickable bars for manual character selection. Developed by "Nosey" Nick Waterman, VA3NNW, this tutor is based on earlier versions by Jim Wilson and a 1977 QST article. A significant October 2019 rewrite incorporated a new WebAudio sound library by AwesomeAidenW, improving offline functionality and mobile support. The content library was expanded to include 3000 top Google words, 2284+ General Service List words, ISO country codes, capital cities, US states, Canadian provinces, UK counties, common names, periodic table elements, quotes, Q-codes, electronic components, ham abbreviations, and example call signs. The software is distributed under the GNU GPL V2 license.

SDR-- is a free and open-source software-defined radio application for macOS, Windows, and Linux, designed for patching together radio components. It allows users to connect a receiver to channels, and channels to speakers, maps, or recorders. The software supports various audio modes including AM, NFM, SSB, CW, FM stereo, RDS, DMR, FreeDV, D-STAR, Fusion, NXDNP, P25, and dPMR. It also decodes events and messages such as ADS-B, ACARS, VDL2, HFDLA, AIS, NAVTEX, DSC, POCSAG, FLEX, ERMES, FT8, FT4, WSPR, APRS, RTTY, PSK, ISM sensors, and time signals. Video modes include SSTV, ATVDVB-S, and DVB-S2. SDR-- offers spectrum, waterfall, constellation, and map displays with decoded messages, and features like scanning, signal identification, satellite tracking, direction finding, and passive radar. It can be controlled remotely via REST, WebSocket, MCP, and event forwarding. Benchmarks indicate higher performance for FM demodulation and DMR speed compared to liquid-dsp, GNU Radio, and dsd-fme. The software can run on a desktop computer or on a server, such as a Raspberry Pi, for remote access.

SWLTools, an iOS application for iPhone and iPad running iOS 17+, provides real-time decoding of various digital modes. It automatically locks onto CW tones, measures sending speed, and collects callsigns, distinguishing valid entries from misreads for a reliable log. For RTTY and SITOR-B, the app allows users to set shift and speed, then automatically tunes to the two tones for text reception, supporting marine bulletins, press agencies, and NAVTEX. The application also decodes WEFAX, building charts line by line for direct saving to the photo library, and processes ACARS aircraft messages, including CRC checks for data integrity and mapping of position reports. Beyond decoding, SWLTools integrates a GPU-accelerated FFT spectrum analyzer, a scrolling waterfall display with frequency cursors, and an adjustable FIR bandpass filter to isolate signals. It supports IQ signal analysis from receivers via two-channel audio interfaces, correcting mirror images. Flexible audio input options include the built-in microphone, USB audio dongles, and Bluetooth sources, with diagnostics for audio routing and buffer status. The app records audio, plays it back, and converts recordings into shareable videos, while decoded texts and charts are also savable and shareable, with all timestamps in UTC.