This document describes the design of a wireless audio transmitter for a TV using infrared transmission. The circuit allows watching TV late at night without disturbing others. It uses an IR transmitter connected to the TV's audio output to transmit the audio signal, and an IR receiver connected to a headphone to receive the signal. The circuit uses transistors, resistors, capacitors, and an IR transmitter and receiver module. It has advantages like low cost, low power consumption, and allowing quiet late-night TV viewing without disturbing others.

1. BY
VIKRAMA S
8TH SEMEEE
UVCE

2.  This circuit allows you to watch your favorite TV
programs late at night without disturbing other family
members.
 Most modern TVs are nowadays equipped with audio-
in/out and video-in/out RCA sockets. Using an RCA-to-RCA
cord, connect the audio output of your TV to the transmitter’s
input.
This transmitter draws only a few mill amperes of current and
doesn’t require on/off switch. It can be fabricated on a small
piece of strip board.
ABSTARCT

3.  To design and implement a WIRELESS AUDIO
TRANSMITTER FOR TV USING IR TRANSMITTER
AND RECEIVER

4. PROJECT BLOCK DIAGRAM

5.  TRANSFORMER OF SUITABLE RATING FOR
POWER SUPPLY
 TRANSISTORS BC548 AND BC 547
 IR TRANSMITTER AND RECEIVER
 RESISTORS AND CAPACITORS
 A HEADPHONE TO BE USED

6. TRANSISTOR
The BC547 transistor is an NPN
Epitaxial Silicon Transistor.
It is used in general-purpose
switching and amplification
BC847/BC547 series 45 V, 100 mA
NPN general-purpose transistors.
The transistor is a "CURRENT"
operated device and that a large
current (Ic) flows freely through the
device between the collector and
the emitter terminals.

7. The BC548 transistor is an NPN
Silicon Transistor.
The BC548 transistor is a
general-purpose transistor in small
plastic packages.

8. It is used in general-purpose switching and
amplification BC848/BC548 series 45 V, 100
mA NPN general-purpose transistors.

9. IR TRANSMITTER AND RECEIVER
The figure shows a typical transmitter or a
receiver
IR transmitter and RECEIVERS are grouped in
OPTO ELECTRONICS field in current
trchnological dictionary. These use Infra Red
ratdiations to transmit data without any
requirements of wires.

10. An infrared receiver , or IR receiver, is
hardware that sends information from an
infrared remote control to another device
by receiving and decoding signals.

11. In general, the receiver outputs a code to
uniquely identify the infrared signal that it
receives.
This code is then used in order to
convert signals from the remote control
into a format that can be understood by
the other device. It is the part of a device
that receives infrared commands from a
remote control.

12. It is a light emitting diode (LED) that is
used in order to transmit infrared signals
from a remote control.
The more they are in quantity and the
better the emitters are, the stronger and
wider the resulting signal is.

13. An IR emitter generates infrared light that
transmits information and commands from
one device to another.
Typically one device receives the signal
then passes the infrared (IR) signal through
the emitter to another device.

14. The working wireless audio transmitter can be
explained in the following slides, with the role of each
component being elaborated.

15. DATA FLOW BETWEEN IR TRANSMITTER
AND RECEIVER

16. Input to the sending end of the
transmitter is from a transformer, whose
rating is decided based on the design.
Typically the Output of the transformer
will be 12V.

17. The audio signal is coupled to the base of T1
by an audio transformer. The T1 pre amplifies
the signal
The transistor T2 drives the IR LED’s which
transmit the sound as IR beams.
The red LED provides fixed bias for theT2 as
well as a power on indication.

18. The photo transistor T3 receives the IR
signals.
The collector of IR is connected to base of T4
which amplifies the signal together with T5 to
regain the audio signal transmitted.
The transistor T6 drives the headphone to
reproduce the sound.

19. The received sound is reproduced and that
can sound can listened in the headphone.

20. Due to wireless transmission, cost is reduced.
This can be used not only in TV applications,
but also in portable music systems.
This can be used where noise volume has to
be reduced.
Can be used as an alternative to Bluetooth
technology, as this consumes lesser power.

21. Simple in construction.
Easy to maintain and repair.
Comparatively the operation cost is less.
Efficient and low cost design.
Low power consumption.
Alternative for Bluetooth

22. There might be disturbance in the output
during transmission via I.R due to external
factors.
For higher ranges, cost increases.
To connect more than one device is difficult.

23. This is an excellent way of reducing the
disturbances caused to others while
watching our favorite TV programs, so
this must be encouraged among the
people.