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WSJT-X, a creation of K1JT, offers specialized digital protocols meticulously optimized for challenging propagation paths such as EME (moonbounce), meteor scatter, and ionospheric scatter. This software excels at VHF/UHF frequencies, and also provides robust performance for LF, MF, and HF DXing, enabling contacts far below the audible threshold. The program decodes signals from ionized meteor trails and steady signals more than 10 dB below the audible threshold, a testament to its advanced digital signal processing. It integrates nearly all popular features from its predecessors, WSJT and WSPR, while adding comprehensive rig control and numerous other enhancements for the serious weak signal operator. Available for Windows, Linux, and Mac OS X, WSJT-X is an open-source project, allowing hams worldwide to download the latest versions and engage in cutting-edge weak signal communication.

The Kenwood TH-F6A handheld transceiver can achieve an extended transmit frequency range of 137-174 MHz, 216-235 MHz, and 410-470 MHz by removing a specific diode and chip resistor from the main PCB. This modification also expands the receive range on the A-band to 142-152 MHz, 216-235 MHz, and 420-450 MHz. For the TH-F7E, the transmit range extends to 137-174 MHz and 410-470 MHz, with a corresponding receive range on the A-band. Performing these hardware changes will reset and initialize the radio's memory contents, necessitating prior backup of important channel frequencies. Instructions are provided for constructing a homemade PC programming cable compatible with the Kenwood TH-G71A, TH-F6A, and TH-F7E. The interface utilizes an RS-232-to-logic (0-3.3V) level-shifter and a full-duplex serial connection, adapting the Kenwood PG-4S cable schematic for the TH-G71's 2.5mm and 3.5mm phono plugs. Specific schematic tweaks include changing R1 from 150 ohms to 1K ohm to optimize power from the serial port and adding a 150K ohm resistor between the Radio TXD and ground to manage the 3.3V I/O pin. Detailed plug pinouts for the 2.5mm and 3.5mm connectors are presented, with the interface's TXD connecting to the ring of the 2.5mm plug and RxD to the shield of the 3.5mm plug. Ground connects to the shield of the 2.5mm plug, while the tips of both plugs are no-connects. Debugging procedures cover verifying positive and negative power rails from the serial port, checking component polarities, and testing level-shifting and inversion functions of the interface. Software setup involves enabling "TC ON" (Menu 15 for TH-G71, Menu 9 for TH-F6) and using Kenwood's MCP programming software.