Search results

Official MixW website where you can download latest version and options for MixW, a widely used multimode software suite for amateur radio operators. The website provides access to various versions of the core MixW application, including legacy releases like Mix 2.21 for MS DOS and more recent iterations up to MixW version 3.2.105. Users can also obtain essential add-ons such as the **Olivia** support DLL, **Q15X25** support DLL, contest DLLs, and serial port emulation drivers. Detailed instructions are provided for Olivia mode operation, emphasizing the critical need for sound card sample rate calibration to ensure proper decoding and signal placement within specific frequency grids to minimize QRM. The page also links to external resources for localized help files in Spanish, Italian, French, German, and Polish, catering to a global user base. An alternative download page by G3VFP is also listed. MixW supports new transceivers for CAT control, including Yaesu FT-991, FT-1200, FT-3000, and Icom IC-7100, IC-7300, IC-7410, IC-7851. It also features an online callbook via QRZ.com.

PA3FWM's software defined radio (SDR) page documents his extensive hardware and software development efforts between 2004 and 2009. Initial experiments utilized a direct conversion receiver with 90-degree phase difference, feeding a PC soundcard at 48 kHz sample rate, covering 24 kHz of spectrum around a 7080.5 kHz local oscillator. This setup, similar to AC50G's QEX 2002 article, allowed for basic I/Q signal processing to distinguish signals above and below the LO frequency. Limitations included fixed crystal frequencies, 16-bit dynamic range, and narrow bandwidth. Subsequent hardware iterations aimed for enhanced performance, incorporating external 24-bit ADCs with 192 kHz sample rates, connected via 10 Mbit/s Ethernet. A **MC145170-based PLL** and programmable octave divider provided a 58 kHz to 30 MHz tuning range. The **Tayloe mixer** was employed, with differential outputs feeding a PCM1804 ADC. An ATmega32 microcontroller handled serial data conversion to Ethernet frames, though without CRC calculation due to processing constraints. Later designs integrated AD7760 2.5 Msamples/second ADCs and a Xilinx Spartan-3 FPGA, enabling direct reception of 0-1 MHz spectrum and eventually 2.5 MHz bandwidth across the shortwave spectrum. Software was refactored to use an initial 8192 non-windowed FFT for efficient high-bandwidth processing. The project culminated in a two-way QSO on 21 MHz using the developed hardware and software, demonstrating transmit capabilities with a D/A converter. The system exhibited a 2.5 MHz wide spectrum display and a zoomed 19 kHz display, capturing signals like ionospheric chirp sounders and RTTY contest activity. Challenges included noise leakage from digital circuitry and cooling for high-power dissipation components.

RSCW demonstrates a Linux/Unix command-line utility engineered for **Morse code** decoding via a computer's sound card. It specifically targets the extraction of weak CW signals from noise, operating on 8-bit, 8000 samples/second audio input, typically from `/dev/dsp`. The program outputs decoded characters to `stdout`, supporting user-specified speeds in words per minute (WPM) and carrier frequencies. While effective for machine-sent signals, it exhibits a 2-second decoding lag and requires manual speed input, making it less suitable for general-purpose, real-time contest operation. The resource details the program's components, including `rscw` (the main decoder), `rscwx` (an X11 graphical auxiliary for spectrum and internal signal visualization), `rs12tlmdec` (a specialized decoder for RS-12 amateur radio satellite telemetry), and `noisycw` (a utility for generating noisy Morse signals for testing). Installation instructions involve downloading a `.tgz` file, compiling with `Make`, and requiring the FFTW library (and GTK 2.0 for `rscwx`). Performance is illustrated with a .wav file example of a 12 WPM, 800 Hz CW signal at 12 dB Eb/N0, showcasing RSCW's near-error-free decoding of a test message. The site provides command-line examples utilizing `sox` for audio conversion and `noisycw` for signal generation, inviting comparisons with other decoding software and human operators, particularly for weak signal conditions.

This resource details the construction of a versatile CW/QRSS beacon, designed around a Microchip _PIC16F84_ microcontroller. The project provides a flexible platform for transmitting either standard CW or very slow QRSS signals, making it suitable for LF, VHF, UHF, and SHF applications. It supports two distinct messages, each configurable for speed (from 0 to **127** WPM for CW, or up to **127** seconds per dot for QRSS) and repetition within a six-phase sequence. The core functionality relies on the PIC's EEPROM, which stores all operational parameters, including message content, transmission speeds, phase configurations, and relay control settings. This design allows for parameter modification directly via programming software like _ICProg_ without altering the main program code. The project includes a detailed schematic, a component list, and an explanation of the EEPROM memory mapping for messages, speeds, phase settings, and inter-phase delays. General-purpose outputs (OUT1, OUT2, OUT3) provide dry relay contacts for external control, enabling functions such as power switching, antenna selection, or frequency changes. A 'TRIGGER' input facilitates controlled starts or continuous free-run operation. Sample EEPROM configurations illustrate how to program specific beacon sequences, including message content and relay states.

SDR# (read SDR Sharp) is a high performance Software Defined Radio application. SDR sharp is a fully featured SDR capable of handling samplerates from kHz level soundcards up to multi hundred MHz dedicated samplers, thanks to its multi-core architecture.

ScopeDSP analyzes sampled-data signals in the time and frequency domains. It can generate, read, write, window, and plot real and complex digital data signals.

A guide to setup and operate on JT-9 mode, including a sample QSO and setup hints by VA3PAW

Around 17% of the U.S. population experiences some degree of Dyslexia, a condition affecting language processing that can hinder amateur radio license candidates, often leading to repeated exam failures despite diligent study. This resource outlines methods for Volunteer Examiners (VEs) and Elmers to identify and assist candidates with cognitive disorders like Dyslexia and **ADHD**, which affects approximately 4% of U.S. adults. It emphasizes recognizing patterns in missed answers, such as spatial placement errors on answer sheets, and suggests reading questions aloud as an accommodation. The author, NC4FB, shares a structured approach developed over three years, involving extensive candidate interviews and a self-study program. This program utilizes specialized software with keyword highlighting and a unique font to improve comprehension for Dyslexic/ADHD candidates. It also incorporates **MP3 audio files** for subelement questions and correct answers, providing an alternative study method for those who benefit from auditory learning. Key elements of the support strategy include repetition, positive reinforcement, and timely progress updates, often visualized with a color-coded table tracking scores of 85 or higher. The goal is for candidates to pass three consecutive sample exams with at least 85% before attempting the actual license exam, demonstrating mastery of the material.

LILYGO specializes in the research and development of IoT solutions, offering a diverse range of development boards. Key products integrate LoRa and GPS capabilities, alongside various display options such as LCD and OLED. Specific examples include the _T-SIM / T-A Standard Series_, _T5 E-Paper S3 Pro Lite_, _T-Halow P4_, _T-Dongle C5_, and _T7-C5_. The company also provides the _T-Solar Kit_ and _T-Sim Shield_, catering to diverse project requirements. Hot sales items feature the _T-Display S3_, _T-Embed CC1101_, _T-Deck Plus_, _T-Embed CC1101 Plus_, _T-Deck Plus Meshtastic_, _T3 LoRa32 V1.6.1_, and _T-Display S3 AMOLED_. These boards often incorporate ESP32 microcontrollers, facilitating wireless communication and display functionalities essential for amateur radio digital modes and data telemetry applications. LILYGO provides entry-level sample code for most products, aiding learners in rapid prototyping and deployment. They also offer customization support for specific customer needs, demonstrating a commitment to supporting both individual makers and larger-scale integrations. The company actively participates in events like Maker Faire Rome, showcasing open-source solutions to the global maker community.