Make a bug from a regular mobile phone. To do this, disable the backlight, ring tone and vibration. In General make the phone appearance gave no signs of life. If the mobile is not a pity, to be more convincing, can be slightly cracked panel.
Then set your phone to auto answer, for example, 5 seconds, and in the time of need just call on him. Hide it in an inconspicuous place (in a flower or a bookcase). The disadvantage of this method is that the battery life of the phone is limited, but if you have time to do a recharge from the network. Well, a signal from a mobile can detect any VHF receiver that will quickly give your bug.
Purchase phone GSM bug install it in the phone's memory. The bug will automatically independently to carry out the wiretap, intercept SMS, determine the location of the phone owner, and send that data to the server. This is the most simple and effective way to make a bug from a mobile phone, though not the cheapest.
Use a highly directional microphone, which you can make as yourself, and to buy on the Internet or on the radio. To disguise it by setting in the headset from the phone, so that others will not suspect anything extra.
Make microphone bug for this scheme. This bug gives the signal, which can be taken at a distance of about 300 meters on the receiver is the player in the absence of direct visibility. Sensitivity will allow you to overhear a loud conversation in the room, and if NCH tract Supplement gain stage, you can hear even a whisper.
Use the voice recorder. Today, there are recorders of different sizes, down to miniature journalism, so masking should not occur. One problem – the limit of the recorded information, so this method is not suitable in all cases.