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Ramin Farmani - Ahmad Bahreyni

Summer 2009

Design and Develop a

88-108MH !"#$ %8&m'FM (ransmi))er

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*re+a,e

Designing a Transmitter

FM & AM a brief introduction

Class C Power Amplier a briefintroduction

Designing Circuit

Schematic and PCB Dipole and agi Antenna

 Tuning

!"#$"#$%%#'% M() *+!,att FM Transmitter

-

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Designing a (ransmi))er

Analog & Digital Comple.it/

0.tra Comple.it/ in 1F 0lectronic

Dene our Pro2ect 1e3uests 4o5ernmental 1ules in Countries

!"#$"#$%%#'% M() *+!,att FM Transmitter

*

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FM AM Modula)ion

FM & AM in Broadcasting

AM a Brief 6ntroduction

FM a Brief 6ntroduction

!"#$"#$%%#'% M() *+!,att FM Transmitter

7

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./ASS . AM*/FR

!"#$"#$%%#'% M() *+!,att FM Transmitter

!

8ce

6c

Class A

Class AB

Class B

.lass .

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./ASS B AM*/FR R$

 The Class B amplier is biased at cuto9: in other words there is no bias+

 The amplier relies on the input signal to bias the transistor+ The rst '+; 5olts of thesignal in is lost because the transistor does not turn on until the base 5oltage reaches'+;8+

Amplier is 5er/ e+

Amplier is used to amplif/ power in situations where wa5eform is not important ?power

supplies@

!"#$"#$%%#'% M() *+!,att FM Transmitter

$

+V

12V

1kTP1

1.0 kHz

-5/5V

1k

NPN

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./ASS . BAS34

 The Class C amplier has a negati5e 5oltage at the base and )ero 5olts at the

emitter+ The Base0mitter 2unction is re5erse biased+ The transistor will turn on at a

signal 5oltage of 7+;8+ The transistor will onl/ conduct a small pulse through to the

collector output+

Amplier is 5er/ e

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CASS C APP6CAT6E

Collector resonant circuit responds to an impulse b/ =ringing> at its resonant

fre3uenc/+ This is liGe pushing someone on a swing+ A sharp short push each trip

allows the swing to oscillate bacG and forth at its resonant fre3uenc/+ Collector

impulses occur b/ design at the resonant fre3uenc/ of the tanG circuit+ 1esonant

circuit continues to ring and restores the sine wa5e at the output Class C Amplier is

used in radio"1F applications and is also called a =tuned> amplier+

!"#$"#$%%#'% M() *+!,att FM Transmitter

%

       1     u      F

  C11uH

-4V DC

+V

12V

TP3

1.0 kHz

-5/5V

1k

NPN

Positi5e alternations lled in b/tanG circuit ring

1esonant ?tanG@ circuit

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Designing .ir,ui)

Audio Preamplier

!"#$"#$%%#'% M() *+!,att FM Transmitter

H

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Designing .ir,ui)

FM Modulator and Escillator

!"#$"#$%%#'% M() *+!,att FM Transmitter

#'

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!"#$"#$%%#'% M() *+!,att FM Transmitter

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