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The article describes adding lightning protection to Beverage antennas, which are long wires susceptible to lightning strikes. The author reviews common lightning protection circuits and discusses their components. They then detail their design based on existing methods, highlighting choices for components and reasoning behind them. Finally, the author presents the completed design and its implementation on their Beverage antennas.

Demonstrates the construction of an active loop converter specifically designed for the Low Frequency (LF) bands, addressing common localized noise interference in LF reception. The design integrates a sharply tuned circuit and a tuned loop antenna, utilizing the loop as the sole tuned inductive element. By applying positive feedback, the converter significantly increases the loop's effective Q, achieving factors between 1000 and 2000, which sharpens tuning and reduces noise. The circuit employs an _NE602_ mixer stage, feeding its output to an HF receiver, with a crystal-locked local oscillator at 4 MHz. A 20-turn, 0.8-meter square loop antenna with 500 uH inductance is detailed, connected via 2 meters of figure 8 flex cable. The converter offers three selectable frequency bands: 195-490 kHz, 150-220 kHz (including the New Zealand amateur band), and 128-160 kHz (covering the European amateur band). Performance measurements indicate an effective 3dB bandwidth of approximately 100 to 200 hertz at 200 kHz. The article provides insights into component selection, including an _LF353_ op-amp and a trifilar wound transformer on a ferrite core. Sensitivity figures are presented, showing 7.5 uV of converted output per 1 uV/meter signal strength into a 50-ohm load, or 37.5 uV into an _FRG7_ receiver, highlighting its capability to extract weak signals from noise.

Details the Virtual COM Port (VCP) drivers for Silicon Labs CP210x USB to UART Bridge devices, which are crucial for establishing serial communication between a host system and CP210x-based hardware. It covers driver availability for Windows, macOS, Linux, and Android, highlighting the necessity of these drivers for operating CP210x products as a virtual COM port. The resource also mentions the option for direct access drivers and references _Application Note 197_ for comprehensive serial communication guidance. The page specifies that the CP210x Manufacturing DLL and Runtime DLL have been updated, requiring their use with v6.0 and later of the Windows VCP Driver, impacting specific application note software downloads like AN144SW.zip. It notes that Linux 3.x.x and 4.x.x driver versions are maintained within the _Linux kernel tree_ at www.kernel.org, ensuring ongoing support. Legacy OS software is also provided for users requiring support for 5.x drivers, ensuring broad compatibility.