RCA said it will write down $140 million.

But RCA said that the write-down of the value of assets in its satellite business will be offset by a $93-million gain from its sale of Hertz to United Airlines and that third-quarter earnings will exceed the year-earlier profit of $78 million. In addition, RCA said weak demand is prompting it to close its semiconductor plant in West Palm Beach, Fla., next year, eliminating 350 jobs. It will also restructure and sell off pieces of its broadcast systems division based in Gibbsboro, N.J., which makes studio equipment such as cameras. Up to 600 employes will be affected.