Here is our PPT Presentation on 4th Year Final Year Project on the topic 27MHz Walkie Talkie. However due to lockdown situation in our country for Coronavirus Pandemic we were unable to make this project on the ground.
4. 1) Portable, two-way radio transceiver
2) Walkie Talkies were first patented in 1938 by Al Gross. They were first used
by the military.
3) Typical walkie-talkies resemble a telephone handset, with a speaker built into
one end and a microphone in the other and an antenna mounted on the top of the
unit.
4)its is normally in receive mode; when the user wants to talk they must press a
"push-to-talk" (PTT) button that turns off the receiver and turns on the transmitter..
INTRODUCTION
5. • The walkie talkie communication system consists of two receiver
and two transmitter circuits. One receiver and one transmitter
circuits are for each walkie talkies. The general structure of this
system :
6.
7. 1)A transducer converts Voice into of electrical signal. Microphone and the
loudspeaker are the transducers
2)Then amplifier modulator modulated the amplitude of the electrical signal
3)In the receiver circuit , demodulator separates the message signal from
modulated signal , and amplifier increases the message signal to be heard
easily. Loudspeaker converts the electrical signal to the sound
4)Transducer and the receiver must be in the same frequency interval to
communicate each other
5) A walkie-talkie is a half-duplex communication device.
8. TYPES OF
COMMUNICATIONSimplex –
o A can talk to B
o Radio, T.V. broadcasting, CD/DVD ROM
o Simplest type, requires one transmitter and one receiver
Duplex –
o A and B both can talk to each other simultaneously
o Telephone, Telegraph Complex, requires two
transmitter and two receiver at both ends
o Needs two different channels for simultaneous
transmission
9. Half-Duplex –
• A and B can both talk to each other but not simultaneously
• Fax, CD/DVD RW Needs one single channel for transmission
• don’t require separate transmitter and receiver Same antenna and
circuitry may be used for both transmission and reception
10. This classic walkie talkie consists of both
27 MHz transmitter and receiver all in one
circuit
11. Project Simulation Problem:-
We have tried for a project simulation
On Multisim Software. However we didn’t
Get 27 MHz Crystal Circuit in Multisim database.
So we tried to replaced the 27 MHz Crystal
Crystals with 27 MHz 5 transistors circuit but
Unfortunately during updating database Of
Multisim our system get corrupted.
12. ADVANTAGES OF WALKIE TALKIE
• Unlimited communication
• Instant communication
• Adaptable
• Simple & Easy to use
• Free Means of Communication
• Emergency & Safety
• Device is cheap
13. DISADVANTAGES OF WALKIE TALKIE
• Limited by Distance
• One at a time
• Limited to a Particular Battery Life
• Tapping in
• Clarity of sound
14. Project Progression Difficulties
Due to current situation of Covoid-19 Pandemic a
Nationwide Lockdown is going on due to which its
currently impossible to get together with group
members to complete the project here by we have
attached a project simulation with this presentation
15. CONCLUSION:-
It’s a great little device to have some fun with it & can be used
for good practical users as well- for camping trips, construction
work, commercial use etc. And it isn’t like that they are too
expensive either there are even businesses that rent walkie
talkie & developed it for common people for commercial
profits. Walkie Talkie means completely Free mode of
communication therefore its have potential to hit the market
with high profits.