The LL4501 is a C-core line output transformer. Standard version is gapped for DC current. LL4501G is gapped for a smaller current and has been used in telephone hybrid circuits. Pin configuration (as seen from PIN side) 4, 3, 2, 1 8, 6, 5, LL4501 usage (turn ration 1 : 1) pin 1 primary signal in (+) pin 3 primary side ground pin 2 + pin 4 connect pin 8 out + pin 6 out - pin 5 Faraday shield. Ground.