Cell phone Calling Detector.(Electronics Project)

Device purpose:

This circuit was designed to detect when a call is incoming in a cellular phone (even when the calling tone of the device is switched-off) by means of a flashing LED.
The device must be placed a few centimeters from the cellular phone, so its sensor coil L1 can detect the field emitted by the phone receiver during an incoming call.
Circuit operation:

The signal detected by the sensor coil is amplified by transistor Q1 and drives the monostable input pin of IC1. The IC's output voltage is doubled by C2 & D2 in order to drive the high-efficiency ultra-bright LED at a suitable peak-voltage.
Notes: * Stand-by current drawing is less than 200µA, therefore a power on/off switch is unnecessary. * Sensitivity of this circuit depends on the sensor coil type. * L1 can be made by winding 130 to 150 turns of 0.2 mm. enameled wire on a 5 cm. diameter former (e.g. a can). Remove the coil from the former and wind it with insulating tape, thus obtaining a stand-alone coil. * A commercial 10mH miniature inductor, usually sold in the form of a tiny rectangular plastic box, can be used satisfactorily but with lower sensitivity. * IC1 must be a CMos type: only these devices can safely operate at 1.5V supply or less. * Any Schottky-barrier type diode can be used in place of the 1N5819: the BAT46 type is a very good choice.

Parts:

R1____________100K 1/4W Resistor
R2______________3K9 1/4W Resistor
R3______________1M 1/4W Resistor

C1,C2_________100nF 63V Polyester Capacitors
C3____________220µF 25V Electrolytic Capacitor

D1______________LED Red 10mm. Ultra-bright (see Notes)
D2___________1N5819 40V 1A Schottky-barrier Diode (see Notes)

Q1____________BC547 45V 100mA NPN Transistor

IC1____________7555 or TS555CN CMos Timer IC

L1_____________Sensor coil (see Notes)

B1_____________1.5V Battery (AA or AAA cell etc.)

Thanks to www.redcircuits.com
Sheraz Awan
Pakistan

Category:

Education

Tags:

• cell
• phones
• physics
• electronics
• 555timer
• projects
• calling
• LED
• digital
• analog
• coil

[puffleboy101]

It's phone not fone

[shezi79]

@puffleboy101 ooo ... wow u r very intelligent ... in american English u can write fone..ok

[aarongracias]

hey from wer did u get the inductor???

[shezi79]

@aarongracias it can b found in a AM radio

[TheMerrry]

oo very very nice project....i'll try to make it..can anybody tell me the detail of the components used?

[shezi79]

@TheMerrry see device purpose

[jawasathu]

hi.. i need to know the distance between the mobile and the circuit to detect ??? and is that possible to increase the distance. because am in need to do my final year project kindly do help me please...!!

[10ahsanmerchant]

yar tum kanha rehte ho!!! plzz tell me i am also in pakistan!!!!yar mere ko sikhao na plzzzzz

ya koi tumhari persnall id ho to do yar plzzz

[GTXAbunada]

@shezi79 Listen mate, you pulled "fone" out of your ass, and no its not American English. Plus, your music is fucking hideous.

[brycewatsonfromsherm]

@shezi79 In American English you can't write fone....it's still phone

[jauntyjoshi]

all spellings are right fone it has not only p then will become phone

Leave him/her for mistake

[fukin666]

fuckin song

[nokia14354]

hey which type of wire did u used in senser coil plz reply me

me to doing this project not getting ready because of this

[captainsenthilbalaji]

this song is from 3idiots right??



[akrulex]

there's only 1 inductor in the description? why u used two? one is in spiral and other one is in circular box ?

[sindredit]

What is that music? :S