The DATA line is held HIGH (+5V) by a pull-up resistor.

have built-in USB ports for this purpose, older or more basic models require an external interface to convert standard computer signals (USB or RS-232) to the specific (0-5V) logic used by the radio's "Remote" jack. Core Schematic Components

: If using a pre-made CP2102 or FT232RL breakout board, identify the Solder the Bridge

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