Smallest water level controller
The record for making the smallest water level controller was set by Pranav Ramesh Rokde (born on October 30, 1995) of Nagpur, Maharashtra. He created a water level controller circuit with a printed circuit board (measuring 28 mm x 28 mm x 15 mm), encompassing components like NPN and PNP transistors, capacitors, resistors, diode and a relay for switching pump. The sensors connected to the water pump prevent overflowing of water, as confirmed on May 11, 2021.