The idea of creating a listening bug to eavesdrop excites the wannabe spy in all of us. It conjures up images of James Bond listening in on enemies talking about useful information that could be used against them as well as images of secret agents overhearing important information. You can create a makeshift listening bug with items you have in your home.
Plug the headset into the mobile phone's jack.
Select "Enhancement in Use" for headset, enable automatic answer, set the ringing volume to zero, and turn off the vibrating alert.
Hide the mobile phone in a location where it will not be seen. In addition, the microphone of the headset must be hidden where it will not be noticed but can pick up voices. If you are hiding it in a room, the mobile phone could be hidden inside a pot under a sofa. If you are hiding it inside a vehicle, hide it under the seat or even in the glove compartment if you can be certain it will not be found.
Call the mobile phone when you want to listen in on a conversation. Since you changed the settings and hid the phone, no one will know the phone is in the area and they will be unaware that you are listening to their conversation.
Although it is not always possible, ensure the mobile phone you are using has its own phone number only you know and a dedicated SIM card. This will decrease the chance of someone calling the phone and listening in on the conversation.
Use the listening bug at your own risk. If anyone discovers you were eavesdropping, you could be sued for violation of privacy.