No, I am afraid we have no data sheet for the LL1518. The LL1518 is a (solid state) line output transformer, similar to the LL1517.
Usage:
Turns ratio 1:1 In+ pin 1 (left bottom, if you read transformer label correctly) In- pin 5 Out+ pin 7 Out - pin 10 (right top) Connect pin 6 + 9 Ground pin 8 Turns ratio 2:1 In+ pin 1 (left bottom, if you read transformer label correctly) In- pin 5 Out+ pin 7 + pin 9 Out - pin 10 + pin 6 Ground pin 8