This document is a project report for an FM radio receiver circuit built by a student named Sourabh Kant in Class XII. It includes a cover page with Sourabh's details, a certificate signed by his teacher certifying the completion of the project, an acknowledgement thanking his teacher for guidance, and several sections describing the circuit design and components. The circuit uses an IC chip and few other passive components to receive FM radio signals and output audio to headphones. Diagrams and pictures show the circuit layout.

1. [1]
Name:- sourabh kant
Class:- XII Section:- A
Roll No:- 12
Exam Roll No:- 9171XXX
Subject:- PHYSICS
School Name:- pioneer convent senior
secondary school.
New delhi:-110041

2. [2]
CERTIFICATE
This is to certify that Master
Sourabh kant of Class:-XIISection:-A Roll No:-12
Exam Roll No;-9171XXX
Has completed his PROJECT in the subject of
PHYSICS as required according to the syllabus
prescribed by the Central Board of
Secondary Education for the academic
session 2014-2015.
V.N.TRIVEDI
Teacher In-charge
UN-KOWN
DATE: 05 -02-2015 Examiner’s Signature
KAMLESH
Principle

3. [3]
ACKNOWLEDGEMENT
It gives me great pleasure to express my gratitude
Towards our Physics Teacher Mr.vivekanand trivedi for his
Guidance, support and encouragement throughout the
duration of my project. Without her motivation and
help the successful completion of this project would
not have been possible.

4. [4]
INTRODUCTION
FM Ratio Receiver Project Report. The FM Band transmission has started very recently in
India but its superior technique and quality has attracted the listeners. Unlike AM, the FM is
a separate band and its frequency ranges from 88MHz to 108 MHz. The FM Band can not be
received by the conventional AM receivers. Each and every AM receiver does not
incorporate FM facility. The present project is a very low cost project and it can be fitted to
any radio receiver/audio system to receive FM transmission. The circuit of this project is
very simple and can be easily assembled.

5. [5]
Antenna
A theoretical study of radiation from a linear antenna (length l)
Power radiated a (p/l)2
This implies that for the same antenna length, the power radiated by short wavelength or
high frequency signal would be large. Hence the effective power radiated by long
wavelength base band signal would be small for a good transmission, we need high power
hence, this also point out to be need of using high frequency transmission.
Modulation
In amplitude modulated communication, propagation of radio waves from the transmitting
antenna to the receiving antenna takes place in the following two important ways :
1. Ground Wave Propagation
2. Sky Wave Propagation.
The transmitted radio waves are supported at their lower edge by the ground. The radio
waves have to be vertically polarized, so as to prevent the short circuiting of the electric field
component of the wave. The radio wave induces current in the ground, over which it passes.
It attenuates to some extent due to partial energy absorption by the ground.
Types of modulations
1. Amplitude Modulation :
In the frequency range 500 kHz. to 30 MHz, amplitude modulation of the signal is employed
and accordingly this frequency range is termed as amplitude modulated band (AM bond).
The earth’s atmosphere is more or less transparent to the electromagnetic waves in AM
band. However, the ionosphere (the topmost layer of the atmosphere) does not allow the
electromagnetic waves in AM band to penetrate it and they are reflected back. When the
frequency of electromagnetic waves is above 40 MHz, they are no longer reflected by the
ionosphere but undergo refraction. Keeping the above facts in view, the amplitude
modulated signal in medium wave frequency range (up to 1500 kHz.) is transmitted by
surface wave propagation or also called ground wave propagation. In the short wave
frequency range (from a few MHz to 30 MHz), the amplitude modulated signal is
transmitted via reflection from the ionosphere. It is called sky wave propagation.
2. Frequency Modulation :

6. [6]
For frequencies of electromagnetic waves above 40 MHz, frequency modulation of the
signal is preferred. In the transmission of TV signals, the frequencies of the electromagnetic
waves waves employed ranges from 30 MHz to 1000 MHz. The transmission of
electromagnetic waves in this frequency range can neither be made by surface wave
propagation nor by sky wave propagation. The surface wave propagation is not possible for
the reason that the ionosphere cannot reflect the electromagnetic waves in this frequency
range. Further, in the frequency range 30 cm. to 10 m. FM transmission are made from small
antennas.
Advantages
Now-a-days there is a necessity of FM projects in the electronic market. Through this project
different FM stations can be tuned but in India. Presently there is one FM channel. As such
the project is designed for one channel to avoid possible damage of the coil in tuning again
and again. The FM transmission is stereo phonic. As such you can connect it to any stereo
deck and enjoy the stereo sound. Now a days two-in-one and radios with FM band are
available in the market. But without replacing your old radio set you can connect this project
to your old radio/two-in-one and enjoy the FM transmission. It is quite economical too.
Unlike AM receivers, the FM receiver is assembled through different stages.
(i) FM Amplifier

7. [7]
(ii) Mixer
(iii) Oscillator
(iv) AGC
(v) Discriminator (Detector)
(vi) Audio Pre-Amplifier.

8. [8]
Integrated circuit
All the functions are performed by the IC-5591 which is employed in the circuit. The audio
signal available from the preamplifier is fed to audio output amplifier for further
amplification. The RF of FM band transmission is fed to pin no. 2 of the IC TA5591 through
the aerial, which also works for FM amplifier, oscillator and mixer stage. A ceramic filter of
10.7 MHz. is connected to the local oscillator pin no. 4, 5 and 6 of IC. A 9 volt DC supply is
fed to pin no. 8 of the IC. Pin no. 10 of the IC is discriminator pin. The audio signal is
available from pin no. 11 of the IC. Pin no. 18, 19 and 20 of the IC are IF amplifier pins
while pin no. 22 and 24 are local oscillator pin. Two trimmers are connected to the circuit.
The range of the frequency can be varied by rotating the trimmers. A gang condenser
equivalent to the value of the trimmer can also be used in place of trimmer if available. This
project can operate in the range of 3V to 12 Volt DC supply. However the trimmers are to be
adjusted to get best reception.

9. [9]
Apparatus required
S.No. Part Qty.
1. IC-5591 1
2. Ceramic Filter 10 MHz. 2
3. Resistance 56 E 1
4. Capacitor 470 PF 1
5. Capacitor 22 PF 4
6. Capacitor .022 3
7. 4.7 MFD/63 V. 2
8. One Pole two way switch 1
FM RADIO RECEIVER CIRCUIT

10. [10]

11. [11]
Build A One Transistor FM Radio
updated designs!
See below for:
My new, improved
One Transistor FM Radio
Click here for:
The new, improved
Radio Shack Special FM Radio
Build
this one transistor FM radio
(my design)
Enlarge: [medium] [large]
or
Build this one transistor FM radio
(Designed by Patrick Cambre)
Enlarge: [large]
See the new improved version on Patrick's web site

12. [12]
My Design
A printed circuit board for the original circuit is available through FAR Circuits. Ask them
for "Andy Mitz'sOne transistor FM radio printed circuit board". The same circuit board can
be modified for the improved one transistor radio.
Introduction
AM radio circuits and kits abound. Some work quite well. But, look around and you will
find virtually no FM radio kits. Certainly, there are no simple FM radio kits. The simple
FM radio circuit got lost during the transition from vacuum tubes to transistors. In the late
1950s and early 1960s there were several construction articles on building a simple
superregenerative FM radio. After exhaustive research into the early articles and some key
assistance from a modern day guru in regenerative circuit design, I have developed this
simple radio kit. It is a remarkable circuit. It is sensitive, selective, and has enough audio
drive for an earphone. Read more about theory behind this radio on the low-tech FM page.

13. [13]
Construction
parts source
Except the the circuit board and battery, all parts are from Mouser Electronics. A complete
parts list with stock numbers is listed below. The circuit board is available through FAR
Circuits. The variable capacitor is available through Electronix Express.
layout
Because this is a superregenerative design, component layout can be very important. The
tuning capacitor, C3, has three leads. Only the outer two leads are used; the middle lead of
C3 is not connected. Arrange L1 fairly close to C3, but keep it away from where your hand
will be. If your hand is too close to L1 while you tune the radio, it will make tuning very
difficult.
winding L1
L1 sets the frequency of the radio, acts as the antenna, and is the primary adjustment for
super-regeneration. Although it has many important jobs, it is easy to construct. Get any
cylindrical object that is just under 1/2 inch (13 mm) in diameter. I used a thick pencil from
my son's grade school class, but a magic marker or large drill bit work just fine. #20 bare
solid wire works the best, but any wire that holds its shape will do. Wind 6 turns tightly,
side-by-side, on the cylinder, then slip the wire off. Spread the windings apart from each
other so the whole coil is just under an inch (2.5 cm) long. Find the midpoint and solder a
small wire for C2 there. Mount the ends of the wire on your circuit board keeping some
clearance between the coil and the circuit board.
a tuning knob for C3
C3 does not come with a knob and I have not found a source. A knob is important to keep
your hand away from the capacitor and coil when you tune in stations. The solution is to use
a #4 nylon screw. Twist the nylon screw into the threads of the C3 tuning handle. The #4
screw is the wrong thread pitch and will jam (bind) in the threads. This is what you want to
happen. Tighten the screw just enough so it stays put as you tune the capacitor. The
resulting arrangement works quite well.
Adjustment
If the radio is wired correctly, there are three possible things you can hear when you turn it
on: 1) a radio station, 2) a rushing noise, 3) a squeal, and 4) nothing. If you got a radio
station, you are in good shape. Use another FM radio to see where you are on the FM
band. You can change the tuning range of C3 by squeezing L1 or change C1. If you hear a
rushing noise, you will probably be able to tune in a station. Try the tuning control and see
what you get. If you hear a squeal or hear nothing, then the circuit is oscillating too little or

14. [14]
too much. Try spreading or compressing L1. Double check your connections. If you don't
make any progress, then you need to change R4. Replace R4 with a 20K or larger
potentiometer (up to 50K). A trimmer potentiometer is best. Adjust R4 until you can
reliably tune in stations. Once the circuit is working, you can remove the potentiometer,
measure its value, and replace it with a fixed resistor. Some people might want to build the
set from the start with a trimmer potentiometer in place (e.g., Mouser 569-72PM-25K).
Substitutingothercomponents
Many of the parts are fairly common and might already be in your junk box. Only certain
component values are critical. The RF choke should be in the range of 20 to 30 uh, although
values from15 to 40 uh might work. The tuning capacitor value is not critical, but if you use
values below 50 pf you should reduce or remove C1. The circuit is designed for the high
impedance type earphone. Normal earphones can be used, but the battery drain is much
greater and the circuit must be changed. To use normal earphones, change R3 to 180
ohms. Q1 can be replace with any high-frequency N-channel JFET transistor, but only the
2N4416, 2N4416A, and J310 have been tested. A MPF102 probably will work. C2 is not
too critical; any value from 18 to 27 pf will work. C7 is fairly critical. You can use a .005 or
.0047 uf, but don't change it much more than that.
Improveddesignformoreaudio gain

15. [15]
Chris Iwata recommended some design changes that greatly improve the audio circuit,
making it strong enough for regular earphones or even a small speaker. The same FAR
printed circuit board can be used with some modifications. The circuit board is important to
make sure the tuning end of the radio works properly, so the audio amplifier changes can be
squeezed onto the circuit board without fear of wrecking radio operation. Look closely at
the new schematic for the new components and some changed component values.

16. [16]
.
Part designator Part description Vendorstock number
C1a,C1b 10 pf,50 v,ceramicdisc capacitor 140-50N5-100J
C2 22 pf,50 v,ceramicdisc capacitor 140-50N5-220J
C3 RF tuningcapacitor N14VCRF10-280P
C4 330 pf,50 v, ceramicdisccapacitor 140-50P2-331K
C5,C8 0.001 uf,50 v, ceramicdisccapacitor 140-50P2-102K
C6 0.22 uf,50 v,filmcapacitor 140-PF1H224K
C7
0.0047 uf,50 v,ceramicdisc
capacitor
140-50P5-472K
C9 22 uf,16 v,electrolyticcapacitor 140-XRL16V22
D1
TL431AIZ voltage control Zener
(shuntregulator)
511-TL431AIZ
EPH1 Highimpedance earphone 25CR060
L2 22 uh RF choke 542-70F225
Q1 2N4416A JFET transistor 510-2N4416A
R1 470K, 1/4 w,resistor 291-470K
R2, R3 1K, 1/4 w,resistor 291-1K
R4 10K, 1/4 w, resistor 291-10K
R5 1M, 1/4 w,resistor 291-1M

17. [17]
R6 100 ohm,1/4 w,resistor 291-100
S1 Small SPSTswitch 10SP003
screwsfor C3 screwsfor mountingC3(2 needed) 48SS03
nylonscrew #4 nylonscrewusedfortuningC3 561-T0440037
batteryconnector mini batterysnap 12BC025
How to build a very simple FM/AM Receiver using
TDA7088 ?
I was browsing the Philips website when I came to this IC : TDA7088 and I said wow , it was the
simplest AM/FM radio I ever saw. I looked on its price on a local electronic parts provider and it was about
5 RON (~1.7$) so it is worth building this radio as a hobby project.
Features of the chip :
 Equipped with all stages of a mono receiver from antenna to audio output
 Mute circuit
 Search tuning with a single varicap diode
 Mechanical tuning with integrating AFC
 AM application supported
 Power supply polarity protection
 Power supply voltage down to 1.8 V.
A simple circuit, taken from the application notes :

18. [18]
As we can see it doesn’t have an audio amplifier so you must build one for it! After another search I found
an extremly simple and low cost (~1.2$) AA done with TDA7050 :

19. [19]

20. [20]
BIBLIOGRAPHY

21. [21]
 NCERT CBSE BOOKS
 HOW STUFF WORKS
 SCICNCE FOR ALL