Connection testor circuit diagram

As electronic lovers we all have to face many troubles when we check some circuits.Among them soldering matters act a major part.Sometimes we can't see those faults with our eye.Some times using multimeter is also some what difficult because we have to read the value of it but by using following circuit diagram you will be able to guess whether the connections of the circuit is ok or not..Here we have used IC 741 .This circuit is operated with 9V power.

   

Note : Build this circuit on a P.C.B