mobile sniffer

1. Detect the use of of a gsm mobile
MOBILE SNIFFER

2. My first project

3. Circuit Diagram

4. Introduction -
 This circuit can detect the use of a gsm mobile in
mobile restricted areas .
 The circuit can detect mobile in silent mode and
also detect the use of bluetooth, sms, call etc.
 For example
 1> examination halls .
 2> high security area .
 3> IN sensitive religious areas.
 4>IN defence.

5. SPECIFICATIONS-BFR96

6. BFR96
 BFR96 Is also called as RF & MICROWAVE
DISCRETE or LOW POWER TRANSISTORS.
 Features
 · High Current-Gain – Bandwidth Product, fT
= 4.5 GHz (typ) @ IC = 50 mA
 · Low Noise Figure – NF = 2.4 dB (typ) @ f =
0.5 GHz
 · High Power Gain – Gmax = 14.5dB (typ) @ f
= 0.5 GHz

7. BFR96
 DESCRIPTION: Designed primarily for use in
high-gain, low noise, small-signal amplifiers.
Also used in
 applications requiring fast switching times.

8. BFR96

9. Diode Specifications
 Limit specifications
 Maximum forward continuous current The product of forward voltage drop and
 current through the diode is the power dissipation of the diode. Power
dissipation
 results in a temperature rise. The maximum temperature that a diode can
operate
 is around 125 C although some parts can operate at over 150 C. It is always good
 to operate any component below its maximum rated temperature. Be very
aware
 that the specification assumes that the diode is operated with an infinite heat
sink
 attached. No such heat sink exists and you must de-rate the specification based
 upon the actual heat sink characteristics and ambient temperature. This very
 important step is often overlooked and the result is diode failure from
overheating
 even if the diode is operated below the specified maximum.

10. Diode specification- 2
 Maximum forward surge current This
specification generally applies to power
 rectifier diodes and addresses the turn-on
transient current when large filter
 capacitors have to be rapidly charged. This
specification is usually several times
 higher than the continuous current rating but
only applies if the duration is brief.

11. Diode specification-3
 Maximum forward peak current This
specification generally applies to power
 rectifier diodes and addresses the fact that
conduction through the diode is only
 for a small percentage of the total AC cycle time.
As an example, a one ampere
 DC average current might require brief peak
currents of ten amperes or more.
 The peak currents cause local hot spots which
can damage the diode if they
 exceed the maximum temperature.

12. Diode specification-4
 Maximum reverse voltage In the reverse direction the diode
is an insulator but only if
 the reverse voltage is not too high. There is some voltage at
which the diode
 structure breaks down and considerable reverse current can
result which will
 usually destroy the diode instantly. The rating is often given
as PIV for Peak
 Inverse Voltage. It is always a good idea to choose a diode
with a significantly
 higher PIV rating than the maximum reverse voltage it will
experience as this
 p r o v i d e s a s a f e t y ma r g i n .

13. Diode specification-5
 Reverse recovery time Because of some
complex physics, a diode that has been
 conducting in the forward direction will
briefly conduct in the reverse direction.
 This results in extra heat being generated in
power rectifiers and limits how high
 the AC frequency can be.

14. Diode specification-6
 Maximum junction temperature This is the
maximum temperature that the diode
 junction should be operated at. It is often in
the 125 to 150 C range.

15. Range of mobile sniffer
 It can detect the activity of the phone from a
distance
 Of eight metres or more.
 If two identical units of this sniffer are placed
in the room, the range can be extended to a
radius of 15 -16 metres.

16. What new thing we learn
 Duration of these project we learn following-
 1> work as a team mate.
 2>use bread board.
 3> connections.
 4> proteus.
 5> good soldering.

17. Resistor Specifications
 Resistors have two main parameters. The
first is its resistance in ohms. The second is
its power rating in watts. There are other
specs such as maximum working voltage
but its power rating and resistance value
are the most important in car audio
systems.

18. Resistor Specifications-2
 If an ideal piece of wire (no resistance) is
connected to the ideal battery and there
would be an infinite amount of current flow
through the wire. In the real world, the
battery (like your car battery) would force
enough current through the wire and create
enough heat in the wire to, at the very
least, melt/burn the insulation off of the
wire and more than likely incinerate
anything that comes in contact with it.

19. Resistor Specifications-3
 RESISTOR COLOR CODES The most common
resistors have a tolerance of plus or minus 5%.
These resistors have 4 color bands. The first 2
color bands give the first 2 digits of the
resistor's value. The 3rd band give the number
of 0's added to the first 2 digits. If the third
band is gold, you multiply the first 2 digits by
.1. If it is silver, multiply by .01. The fourth
band gives the tolerance. Gold is a 5%
tolerance. Silver is 10%. The tolerance band is
generally set off from the other bands. The
other bands are generally set close together.

20. WORKING of mobile sniffer
 The sniffer keeps monitoring the RL level in the
area which gives warning indication .
 The circuit is designed as a sensitive RF detector.
 RF signal` diode IN34 forms the major element.
Along with resistor R1 and capacitor c2, the
diode pick s up RF energy in the area.
 In the standby mode, the output of the diode is
around 0.6 milli volt, which rises to 60 millivolts
when it receives the high energy radiation from
the mobile phone.

21. IC2 LA4440

22. IC2 LA4440-2
 Features
 • Built-in 2 channels (dual) enabling use in stereo and bridg
 amplifier applications.
 Dual : 6W×2 (typ.)
 Bridge : 19W (typ.)
 • Minimun number of external parts required.
 • Small pop noise at the time of power supply ON/OFF and
 good starting balance.
 • Good ripple rejection : 46dB (typ.)
 • Good channel separation.
 • Small residual noise (Rg=0).

23. IC2 LA4440-3
 Features•
 Low distortion over a wide range from low
frequencies to
 high frequencies.
 • Easy to design radiator fin.
 • Built-in audio muting function.
 • Built-in protectors.
 a. Thermal protector
 b. Overvoltage, surge voltage protector
 c. Pin-to-pin short protector

24. IC2 LA4440-4

25.  Since the voltage level from the sensor diode
 Is too weak, three –stage amplification is
provided to give the warning indication
through the speaker.
 output pulses from the sensor diode (1N34)
are preamplified by transistor BFR96(T1).
 It is an RF/microwave lowpower transistor
with high current gain and bandwidth.

26.  It has a high power gain of 14.5 db at 0.5 ghz.
Resistor R2 maintains the feedback and capacitor
C4 keeps the collector voltage of T1 steady for
maintaining the amplification.
 The preamplified signals are fed to the second
amplifier stage built around IC TL071(IC1). It is a low
noise , JFET-input op-amp with low input bias input
and offset current. The BIFET technology provides
fast slew rates to 1c1. here ic1 is designed as an
inverting amplifier with resistor combination of r4
and r5 as potential divider to set half supply voltage
to its non-inverting input.

27.  The inverting input of ic1 receives the preamplified
signals from t1. variable resistor vr1 adjusts the
feedback of the inverting amplifier and hence its
gain.
 The amplified signals from ic1 pass through
capacitor c5 and diode D2 into volume control VR2 .
It also receives the signals from unit 2 identical to
unit 1 through capacitor c6 and diode D3. from
volume control vr2, power amplifier ic2 gets the
amplified signals. Ic la4440 (ic2) is a two channel
audio power amplifier with inbuilt dual channels for
streo and bridge amplifier applications. In dual

28.  Mode it gives 6w, and in bridge mode the output
is 19w. It has good ripple rejection of 46db, small
residual noise built-in over –voltage and surge-
voltage protection, and pin –to –pin protection .
 Here ic2 is wired in bridge config uration using
only one input.
 Normally, a feeble hissing noise is heard from
the speaker, indicating that the sniffer is active.
The hissing noise is due to the detection of RF

29.  In the area. Its loudness can be adjusted using
vr2 . When a mobile phone is activated with
in the range of eight metres, a loud motor-
boating sound is heard through the speaker.
 This is due to a very high RF activity during
the activation of the mobile phone. The
sound is louder if the mobile phone is with a
radius of two metres.

30. Limitation of direct power
supply.
 Power to the circuit is derived from a
12v, 4.5AH rechargeable battery, as AC power
supply may generate audible disturbances in
the circuit.

31. Improvement-
 1> the size of our project is large but not
complicated
 The following changes make project small-
 1>Replace of power supply and use of battery .
 2> Replace the loudspeaker and use buzzer.
 3>use of best antenna which has small size and
good range.
 So these changes make mobile sniffer pocket
size.

32. HELP taken
 1> we take help our guide
 2> proteus
 3>www.google.com
 4> electronic for you.

33. By rsanoria09@gmail.com