G K Agrawal - tutorials on electrical; electronics engineering, op-amp circuits, electronic circuit design, multimeter, clamp meter, signal generator; Oscilloscope use, electrical transformer, 3 phase ac supply, MCB circuit breaker, VFD, IGBT, PWM, Train engine control, power factor, experiment, study tips etc in Hindi & English by G K Agrawal (a person with long industrial experience of product development).
