In this presentation, its described that how to detect or check the MQ-7 sensor using the BC547 transistor, IC7404 NOT gate, Buzzer and Battery.

1. Prepared by:-
Maulik Sanchela=150043111021

2.  As shown Circuit is used for to detects the smoke.
 To detect the smoke we use MQ-7 sensor module.
 We also used BC547, LED, Buzzer, 9v battery, resisters.

4.  The circuit of Smoke Detector is shown as above.
 In Circuit we use 9 v Battery as power supply.
 The smoke detector sensor is MQ-7.
 It’s Output is active Low, it means give us normally output
logic 1, and when it detects Smoke its output is goes to logic
0.
 So to invert it we use NOT-gate 7404.
 Output of Not gate is given to the Transistor BC547.
 When Sensor is detects the smoke , it generates logic 0 and
then it’s inverted it to logic 1 through NOT gate. After that
it given to BC547 transistor.
 So through transister it can ON the Buzzer and LED that
we connect for indication of Smoke.