💻 An Arduino Uno (CH340G clone) reads temperature and humidity from a DHT11 sensor and computes 10+ environmental metrics (heat index, dew point, enthalpy, humidex, vapor pressures, etc.), outputting ...

The Aqara W100 Climate Sensor offers precise temp and humidity monitoring, smart button control, and HomeKit support with Zigbee and Thread compatibility.

Another simple circuits for PWM programming of standard regulator chips, this time Vout is programmable down to zero volts.

RadioLib natively supports Arduino, but can run in non-Arduino environments as well ... Si443x, LR11x0 and SX128x Morse Code using 2-FSK or AFSK for modules: SX127x, RFM9x, SX126x, RF69, SX1231, ...