Arduino Projects - Circuit Construction First make the circuit connection as shown in fig1.1. The 1st Pin(Vcc) of Bluetooth(HC05) is connect to +5v of Arduino Uno and 10th pin(GND) to Arduino Uno
![How long will a 9V alkaline battery power my circuit (Arduino, DHT11, ESP8266)? - General Electronics - Arduino Forum How long will a 9V alkaline battery power my circuit (Arduino, DHT11, ESP8266)? - General Electronics - Arduino Forum](https://aws1.discourse-cdn.com/arduino/optimized/4X/4/6/b/46b91c931386eb5714a2eba9e0550d4495b26a6e_2_505x500.jpeg)
How long will a 9V alkaline battery power my circuit (Arduino, DHT11, ESP8266)? - General Electronics - Arduino Forum
How to power an Arduino board using a 3.3v pin if the minimum voltage required to power an Uno board is 7v - Quora
![SOLVED] - Tx pin not outputting when Arduino Uno is powered by 9v barrel jack - Networking, Protocols, and Devices - Arduino Forum SOLVED] - Tx pin not outputting when Arduino Uno is powered by 9v barrel jack - Networking, Protocols, and Devices - Arduino Forum](https://aws1.discourse-cdn.com/arduino/optimized/4X/6/6/3/663d7eb51015c39fa341aaa6f7b03b773129f073_2_690x465.jpeg)