The stock YL-105 is not linear. The real transfer function (discovered via third-party testing) is: Voltage_out = Vcc * (1 - e^(-k * Moisture)) Where k is approximately 0.45 for loamy soil. A better datasheet would include 5-point calibration (sand, silt, clay loam). You must generate this yourself.
Monitoring dechlorination processes before discharge into natural waterways. yl105 datasheet better
If you are currently debugging a project with this hardware, The stock YL-105 is not linear
// Apply quadratic correction (derived from reverse engineering) // Because the YL-105 datasheet lies about linearity float correctedRaw = -0.0003 * avgRaw * avgRaw + 1.2 * avgRaw - 150; You must generate this yourself
Don't trust the potentiometer blindly. These small trim pots can be sensitive to vibration. Once you find your sweet spot, a dab of hot glue or nail polish over the screw can lock your threshold in place.
Digital Input pin used to switch the radio between RX and TX modes.