DIY Electronic Letter Box using LM358 In 5 Minutes.Easy To Build.

In this video i have modified the old letter box into electronic letter box.With an simple LM358 you can add electronic circuit to your letter box and make your letterbox audible when inserting any letter.

Components Required:

1.Dotted PCB
3.IR transmitter And Receiver
4.5v Buzzer
5.10k Ohm Potentiometer
6.220 Ohm resistor.
7.10k Ohm resistor
8.1k Ohm resistor
9.100 Ohm resistor
11.BC 547 Transister
12.DC Socket

Circuit Diagram: