-
7/31/2019 Mobile Bug[1]
1/17
MAHARAJA PRITHVI
ENGINEERING COLLEGEAVINASHI
-
7/31/2019 Mobile Bug[1]
2/17
MOBILE BUG
Presented by,K.Bhuvana,S.Krishna priya,R.Lakshmi,
C.Vaishnavi.FINAL EEE.
GUIDED BY,Mrs. Ambika B.E
-
7/31/2019 Mobile Bug[1]
3/17
INTRODUCTION
Use of mobile phonesincreasing rapidly inexamination
halls,confidential rooms,etc.
For preveting it we havefound a device calledmobile bug.
This handy, pocket-sizemobile transmissiondetector can sense
thepresence of an activatedmobile
It produces a warning alarmwhich indicates thepresence of mobile
whenthere is an incoming andoutgoing calls
-
7/31/2019 Mobile Bug[1]
4/17
TO BUG A TELEPHONE
-
7/31/2019 Mobile Bug[1]
5/17
-
7/31/2019 Mobile Bug[1]
6/17
BLOCK DISCRIPTION
Signal is receive from antenna.
Given to signal processor, conversion
of current to voltage takes place.Fed to microcontroller to
indicate thepresence of mobile through LCD
DISPLAY with the help of powersupply
Also buzzering sound is got
-
7/31/2019 Mobile Bug[1]
7/17
CIRCUIT DIAGRAM
-
7/31/2019 Mobile Bug[1]
8/17
WORKING
ANTENNA
Small loop RF antennaused for reception ofsignal
SIGNAL PROCESSOR
(RECIEVER)
Signal is captured, detectsthe frequency range from0.9GHz to
3GHz throughthe capacitor of .22uf
-
7/31/2019 Mobile Bug[1]
9/17
WORKING
Here the circuit uses a 0.22F capacitor(C3) to capture the RF
signal from themobile phone.
The lead length of the capacitor is fixed as
18 mm with a spacing of 8 mm betweenthe leads to get the desired
frequency.
Capacitor along with the leads acts as asmall gigahertz loop
antenna to collect the
RF signals from the mobile phone.
-
7/31/2019 Mobile Bug[1]
10/17
The output CMOS transistor is capable ofswinging the output
voltage to within 10
mV of either supply voltage terminal.
Op-amp IC CA3130 (IC1) is used in thecircuit as a
current-to-voltage converter
with capacitor C3 connected between itsinverting and
non-inverting inputs. It is aCMOS version using gate-protected
p-channel MOSFET transistors in the input
to provide very high input impedance, verylow inputcurrent and
very high speed ofperformance.
-
7/31/2019 Mobile Bug[1]
11/17
Cont
Capacitor C5 (47pF) isconnected across strobe (pin
8) and null inputs (pin 1) of
IC1 for phase compensationand gain control to optimise
the frequency response.When the mobile phone signalis detected
by C3, the outputof IC1 becomes high and low
alternately according to thefrequency of the signal asindicated
by LED1.
-
7/31/2019 Mobile Bug[1]
12/17
CONTI.
Capacitor C3 inconjunction withthe lead
inductance actsas a transmissionline thatintercepts the
signals from themobile phone.
-
7/31/2019 Mobile Bug[1]
13/17
MERITS
Low cost.
Portable.
Easy maintainence.
Even a telephonecan be bugged.
Also timer can beengaged instead ofcontroller.
Used in real timeapplications
-
7/31/2019 Mobile Bug[1]
14/17
-
7/31/2019 Mobile Bug[1]
15/17
CONCLUSION
The mobile bug was successfully
setup and tested through LED and
LCD
It was found to detect the mobile
signals in the range of approx 2m.
Efficient device to detect mobiles at
low cost.
-
7/31/2019 Mobile Bug[1]
16/17
THANK YOU
-
7/31/2019 Mobile Bug[1]
17/17
QUERIES ??
