KARD 1 KARG 1 KBEG 53 KEND 58 KTEX 0 DUMMY 1.0 { " " C 2nd of two cards of DRTT2.LIB is just a fixed comment card. $EOF Note that argument AAAAAA is to fill the 6 blanks between the quotation marks. Because of the preceding "{", this is just a comment field, so will be ignored by ATP. As for the data, this is a 1-ohm resistor from new node DUMMY to ground. This should not modify the simulation at all.