Sorry for the delay. Have not been on here much. I run the main output of one selector to the tape 1 input of my receiver (tape 1 or 2 or aux will work). I then have all the outputs of my various tape decks and pc line out running to the inputs of that same selector. Be sure to label them. Then I run the record out from the receiver to the main output of the second selector. Then I connect all the record in's from my decks and pc to those individual inputs of the second selector. That way I can record from and out to any piece of equipment. I labeled one selector box "Out To" and the other "In From" then each button has a label also with the name of the equipment. Hope that helps.