Scientific-Atlanta has begun shipping its new line of Explorer 2100 and 3100 advanced digital set-tops, designed to move the interactive television age forward.

The boxes include a 130-megahertz processor, more cache memory and a next-generation digital decoder. The boxes are also 25 percent smaller that other set-tops on the market.

S-A's set-tops and other cable network equipment sales have helped the company turn a $63.8 million profit. The better than expected performance has made S-A a darling on Wall Street and sent investors scrambling for the stock. The stock opened at 64 13/16 Monday.