Mobile phone sniffer – gsm telephone detector
This handy, pocket-size mobile transmission detector or sniffer can sense the presence of an activated mobile cellphone from a distance of one and-a-half metres. So it can be used to prevent use of mobile phones in examination halls, confidential rooms, etc. It is also useful for detecting the use of mobile phone for spying and unauthorised video transmission.
The circuit can detect both the incoming and outgoing calls, SMS and video transmission even if the mobile phone is kept in the silent mode. The moment the bug detects RF transmission signal from an activated mobile phone, it starts sounding a beep alarm and the LED blinks. The alarm continues until the signal transmission ceases.
Cellphone sniffer circuit diagram

Read the rest here – gsm sniffer
Comments are closed.

about 2 weeks ago
Sir,
plz send me necessary details regarding antena used in this project.and what type of the material that ir used in the place of antena. My email id is amit.ch616@gmail.com
Regards,
amitesh
about 2 weeks ago
Sir,
I am interested in making this sniffer would you please send me its more detail like pcb layout etc on d_unknown_artist@yahoo.com
i’ll be waiting