I am using a heat sink but the transistor overheats instantly when i power on the circuit. I have chekd all parts,values,shorts Can you tell me if the transformer is responsible of this? At the parts list says that the transformer can be 75 to 150VA i am using the 150VA transformer so i think that maybe the current is very big Thank you for replaying. I am desperatly looking for help.Pleas tell me whatever idea you have for making this construction to work! Fraindly GEORGE THANKS