Listening Bug Circuit

We are offering Listening Bug circuit .how great, if you are able to listen the people sitting in the adjoining room. Our listening bug provides an effective way to this imagination. Listening bug is a very simple and inexpensive circuit uses an operational amplifier ic 741 (ic1) and push-pull amplifier using transistors for amplification of a signal.

About the circuit :
The sound signals generated in the nearby room (even at a distance of 5 meters) are received by condenser microphone shown in the circuit diagram. The microphone converts the sound signals into electrical signals that are amplified by ic1. The output is again amplified by push pull amplifier, which consists of npn and pnp transistors namely t1 and t2 respectively. This amplified output is then given to 8w loudspeaker, which converts these electrical signals into corresponding sound signals that can be heard.
Note :
The microphone should be placed near to pcb for good results. If you want to locate it at 6 to 8 inches longer then shielding cable must be used with respect to ground for good results.