# Music Box

## Music Box

Author – Arpita Kashyap

# Introduction

It is which a device produces automatic sounds by the use of set of pins placed on a revolving cylinder or disc. In other words, we can say that it is a box which plays a tune when the box is open.

# Block Diagram of Music Box

When the power supply is switched on, supply reaches to pin number 4 and 8 of 555 Timer IC 1. Here IC1 (U1) is in astable mode. Then at pin number 3 of IC1, pin number 14 of Decade counter 4017 is connected. Pin number 14 of Decade counter act as a clock pulse. From output pins of Decade counter some diode and resistors are connected which are connected to the pin number 5 of 555 Timer IC2. A speaker is connected at pin number 3 of IC2 (U2) .

## Components Requirements

1. 555 Timer IC (U1,U2)
3. Resistors-33k (R1,R2)
4. Resistors- 10k (R3,R5,R9)
5. Resistors- 15k (R4,R7,R10)
6. Resistors- 22k (R6,R8)
7. Capacitors – 10µF (C1,C3)
8. Capacitor-10nF (C2)
9. Diode -1N4148 (D1,D2,D3,D4,D5,D6,D7,D8)
10. Speaker (LS1)

# Circuit Diagram of Music Box

Circuit Diagram of Music Box

When the power supply is switched on, the supply reaches to pin number 4 and pin number 8 of 555  Timer  IC1 (U1). The IC1 works in astable mode. The resistor 1k is used between output (pin number 3) and pin number 2 and 6 so that they do not short together. The output of 555 Timer IC1 act as a clock pulse for Decade counter at pin number 14, as the operating speed of 555 Timer IC1 changes, the frequency applied at counter 4017 changes. The Decade counter operates sequentially from Q0 to Q9 as the voltage signal is applied. At output of each counter 4017, a diode 1N4148 and resistors are connected in series.

The output of set of resistors and diodes are connected to pin number 5 of 555 Timer IC2 (U2). When the output of counter goes high, the IC2 oscillates at a specific frequency. At pin number 3 of IC2 the speaker is connected which is used to produce sound. When the sound is produced on the speaker , this whole process is repeated continue and the music box will produce tones.

# Applications

1. It is used to produce different tones in kids playing mobile phones.
2. It is also used in dolls or other thing for different music.
By |2018-12-03T22:53:14+00:00May 22nd, 2017|555 Timer Projects, Articles|0 Comments

#### Author

Posted by
Arpita Kashyap doing M.Sc in physics. Her field of interest is embedded systems, nanotechnology etc.
May 22nd, 2017