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Demonstrates CW Decoder Logic, a freeware application for Windows Vista SP2, 7, 8, and 10, designed to decode Morse code signals. The software incorporates an optimized 80 Hz DSP filter, enabling reception of CW signals across a speed range of 5 to 60 WPM. Key features include automatic signal tracking within a 3 KHz range, real-time speed detection, and an auto squelch function, enhancing decoder sensitivity and accuracy. The application provides station selection directly on a waterfall display and includes a "Tips" feature for word annotations. It supports sending decoded text to external logging software via UDP protocol, with a logger source code example provided for developers. Configuration options allow users to set speed limitations and customize interface elements. Released initially on October 17, 2016, with subsequent updates, the program requires Microsoft .NET Framework 4.5 or higher. Changelogs detail improvements such as increased program stability, code optimizations for speed, and fixes for display issues across different Windows versions.

Presents the design and construction of the OK2FJ Bigatas, a portable, automatically tuned vertical antenna covering 80 through 10 meters. It details two distinct control systems: one utilizing BCD band data from Yaesu FT-857/897 transceivers, and another employing voltage level sensing for the Yaesu FT-817. The resource provides specific instructions for building the antenna's radiating element, loading coil with switchable taps, and the control circuitry, emphasizing the use of readily available components. The article outlines the physical construction of the antenna, including the use of duralumin tubes for the radiator and a PVC tube for the coil form. It specifies coil winding details, tap points, and the integration of radial wires for ground plane operation. The control electronics section provides schematics and component lists for both the BCD decoder (using a 74LS42 IC) and the voltage comparator (using an _LM3914_ bargraph driver), enabling rapid, automatic band switching without the minute-long tuning delays common in other systems. Crucially, the antenna achieves rapid band changes, with typical SWR values centered on common operating segments, such as **3.7 MHz** for 80m SSB. It also discusses modifications for CW operation on 80m and the trade-offs between antenna efficiency and full-range automatic tuning on higher HF bands, where manual adjustment of radiator length is suggested for optimal performance on 15m, 12m, and 10m. The resource includes construction photos and a discussion of cable requirements for reliable operation.

The SDRcom platform provides a unique browser-native Software Defined Radio experience, emulating a traditional radio with a physical VFO dial, switches, and an analog meter. It integrates a high-resolution 64k FFT waterfall display, supporting essential modes like AM, FM, SSB, and CW. The **SDRcom Blue** version interfaces with SDRplay® receivers via a local WebSocket, while the free **Red Lite** version supports RTL-SDR V3/V4 dongles through WebUSB, including basic audio EQ and 100 memory slots, along with FT8 decoding. For advanced operators, the Red Pro version expands capabilities with 1000 memory slots, upgraded high-resolution waterfalls, and enhanced W4PAH FT8, FT4, and WSPR decoder engines. It also incorporates 4-band DSP noise reduction and an intelligent band scanner, proving beneficial for weak-signal work. The Network edition extends functionality to access hundreds of global remote SDRs, and an ADS-B aircraft decoding feature with 3D positioning and mapping is also available. All SDRcom applications are designed to run directly in a web browser, eliminating the need for any software installation. This approach simplifies access and setup for radio enthusiasts, from casual SWLs to dedicated digital mode operators, allowing immediate engagement with the airwaves.