CONTENTS

•INFRARED COMMUNICATION•INTRODUCTION•COMPONENTS USED•IC UM66- MELODY GENERATOR•PRECAUTIONS•CIRCUIT DIAGRAM•CIRCUIT OPERATION•APPLICATIONS•ADVANTAGES & DISADVANTAGES•CONCLUSION

•Now-a-days everything in this world is getting wireless. Infrared rays’ transmission

is one of the most important ways of wireless communication.

•According to the infrared communication, for a distance of about 10 m from a

communication object the communication can be performed without performing

connection via a cable, and the like, which is convenient for use, and which provides

an advantage that the communication can be realized with a simple constitution as

compared with the communication using radio waves.

•From such advantage, the infrared communication is preferably applied to small

apparatuses such as a note type personal computer and a portable information terminal.

INFRARED COMMUNICATION

INTRODUCTION

• Using this circuit, audio musical notes can be generated and can be heard up to a

distance of 10 meters.

• The receiver can be placed at a maximum distance of 1 meter from the transmitter

without any considerable noise interference.

• However the communication distance can be improved by using Far IR LEDs. The

range of communication can be increased to about 250 meters by using Far IR LEDs.

•This project emphasizes the way by which music is generated and driven by IR rays

and gives an explanation to the one of the methods of receiving IR rays without

considerable noise interference.

ABSTRACT

•The main idea behind the project is to generate musical notes by infrared radiations. •The infrared radiations are transmitted and received by IR LEDs and phototransistor respectively.•This project emphasizes the way by which music is generated and driven by IR rays .• This circuit uses a popular melody generator IC UM66 that can continuously generate musical notes.•The melody produced is heard through the receiver’s loudspeaker.•For maximum sound transmission the IR LEDs should be oriented towards IR phototransistor.•It can be used in wireless music systems , mobile gadgets and cc cameras.

COMPONENTS USED

•MELODY GENERATOR – UM66• LED•OPERATIONAL AMPLIFIER -IC741•IR LED•PHOTOTRANSISTOR- L14F1•AUDIO POWER AMPLIFIER-LM386

IC UM 66 MELODY GENERATOR

PIN 1 OUTPUTPIN 2 +VccPIN 3 -Vcc

• This is the simplest ever musical calling

bell that can be easily built. It uses the musical

3 pin IC UM66 and a popularly known

Transistor BC548b.

• Here the musical IC UM66 generates the

music when it receives supply and drives a

small speaker through a class c amplifier using

silicon transistor BC548b.

• The UM66 series are CMOS IC’s designed

for using in calling bell, phone and toys.• It has a built in ROM programmed for playing music. The device has very low power consumption.

IC UM 66 cont.•The melody will be available at pin3 of UM66 and here it is amplified by using Q1 to drive t he speaker.

•Resistor R1 limits the base current of Q1 within the safe values. Capacitor C1 is meant for noise suppression.

• The volume of the sound of this circuit is so

much that it can be used as a calling bell.

•In this circuit please don't give the supply

beyond 3 volt without modification as the IC

may got damaged.

•The circuit should not be run in Rechargeable

battery also if the Speaker resistance is less

than 8 Ohm and may burn the Transistor.

PRECAUTIONS

•Never connect the IC in reverse supply connection•Power supply must be between 1.5V & 4.5V .•Do not exceed 4.5 V. •Speaker can be driven with external NPN transistor. •Melody begins from the first note if power is reseted. •Assemble the circuit on a good quality common board.•If transistor HE8050S is not available use any NPN transistor like BC548 or 2N2222.

TRANSMITTER CIRCUIT

CIRCUIT DIAGRAM

RECEIVER CIRCUIT

•The IR music transmitter works off a 9V

battery.

•This figure shows the circuit of the IR music

transmitter. It uses popular melody generator IC UM-

66 (IC1) that can continuously generate musical

tones. The output of IC1 is fed to the IR driver stage

(built across the transistors T1 and T2) to get the

maximum range.

•Here the red LED (LED1) flickers according to

the musical tones generated by UM66 IC, indicating

modulation. IR LED2 and LED3 are infrared

transmitting LEDs.

•For maximum sound transmission these should

be oriented towards IR phototransistorL14F1 (T3).

CIRCUIT OPERATIONTRASMITTER:

• The IR music receiver uses popular op-amp IC

µA741 and audio-frequency amplifier IC LM386

along with phototransistor L14F1 and some discrete

components (Fig. 2).

• The melody generated by IC UM66 is transmitted

through IR LEDs, received by phototransistor T3 and

fed to pin 2 of IC µA741 (IC2). Its gain can be varied

using pot meter VR1. The output of IC µA741 is fed

to IC LM386 (IC3) via capacitor C5 and pot meter

VR2.The melody produced is heard through the

receiver’s loudspeaker.

• Pot meter VR2 is used to control the volume of

loudspeaker LS1 (8-ohm, 1W).

RECEIVER:

APPLICATIONS

APPLICATIONS:

1.Wireless Music Systems.

2.Mobile gadgets.

3.CC cameras

4.Remote controls

5.Infrared lasers are used in communications

ADVANTAGES:

1.Highly sensitive

2.Two stage Gain control

3.Very low noise

4.Low cost and reliable circuit

5.Can transmit up to 10 meter

DISADVANTAGES:

1.Not for long distance

2.work in fixed range

3.Noise if object between transmitter and receiver

ADVANTAGES & DISADVANTAGES

CONCLUSION

•IR ray communication is very easy to understand and simple to implement.•It finds various applications in short distance field of communications. •It is one of the best ways of building wireless gadgets. •In future there is scope of building virtual environment using the principles of IR ray transmission and reception. •Virtual gaming which also employs IR reception techniques is still in research process which is soon going to rule the world of gaming.