“If you wish to use the module as stand alone, you can connect the OLED and a geiger on the + and OUT pins, 5V supply from a battery (voltage regulator NOT included) and you can see the voltage ...

Required Parts 1 x ATMega8 1 x L293D motor driver 1 x HC-05 Bluetooth module 1 x 16MHz Crystal 1 x AMS 1117 5V linear voltage regulator 2 x DC motor 2 x 3.7V Battery 1 x Battery holder 1 x LCD 16×2 ...

Over-voltage Protection Module to handle direct connection of voltage regulators to a 5V battery using standard 1.8V IO devices ...