Symbol Technologies ( SBL), a maker of bar code and scanning technology, said the Securities and Exchange Commission has launched an investigation into its revenue practices from 2000 to 2001. In its quarter filing, Symbol disclosed that the inquiry concerns the timing and amount of revenue received over that period. The company said it is cooperating with the SEC and has produced documents. Symbol also said it has begun its own investigation into these issues, using an outside law firm and independent accounting firm. It expects to conclude its inquiry by the fall of 2002. As a result of the investigations, Symbol said it could be required to restate revenue for some or all of the quarters in question. On the news, the stock was lately off $1.05, or 11.6%, at $8.