Apple Computer Inc duly announced its two new printers yesterday, as the single-user Personal LaserWriter SC, at $2,000, and the multi-user Personal LaserWriter NT, at $3,300. The SC uses the QuickDraw graphics routines in the Mac to create text and images and has 1Mb 68000 to provide 300 dot-per-inch resolution, with Times, Helvetica, Courier and Symbol typefaces in sizes 9 to 24 point on floppy disk. It uses SCSI and can be upgraded to the NT by replacing the controller board. The NT has Adobe PostScript, AppleTalk interface and can be used by MS-DOS, OS/2 or Unix-based systems as well as the Mac via an optional LocalTalk PC card. It has an RS-232 serial interface via which users can print non-Post Script documents using built-in HP LaserJet Plus or Diablo 630 printer emulation. It has a 2Mb 68000 CPU upgradable to 8Mb and 35 typefaces. The printers use the Canon Inc LBP- LX laser engine and are available.