National Semiconductor Corp, Santa Clara, California says that it is now expecting to report a significant operating loss for its fiscal second quarter, which ends on November 27. It says that the problem this time is weakened performance in its semiconductor operations. The company cited a sharp decline in bookings and sales in its distribution channel, as well as the overall softness in the semiconductor market, as the principal factors affecting its performance. On the other hand, it says that expects second quarter operating performance for its troublesome Information Systems Group, a large part of which is believed to be for sale, to show significant improvement over that of the first quarter, due primarily to strengthening in demand for National Advanced Systems large mainframes, and large capacity disk drives. Moreover Hitachi Ltd is understood to have accomodated NatSemi over the fall of the dollar against the yen by cutting its transfer prices for its mainframes by 10%. In the first quarter of fiscal 1989, Nati-onal Semiconductor reported a net loss of $30.5m, which included a one-time pre-tax restructuring charge of $16.6m in the Information Systems Group.