The Tektronix TDS600A Series of Digitizing Oscilloscopes are useful in digital design, manufacturing test, telecommunications, and R&D applications. The TDS600A series has infinite and variable persistence displays, 25 automatic measurements, waveform pass/fail testing, a 3.5 in. DOS format floppy drive, a VGA-output to an external monitor, and either two of four input channels, based on the oscilloscope. The TDS644A is the only model in the series with a color display screen; the others all have a monochrome display. A GPIB port is standard on each oscilloscope, as are comprehensive triggering capabilities (including glitch, edge, and logic).