The Tektronix TDS 520A, 524A, 540A, & 544A Digitizing Oscilloscopes are portable, four channel instruments suitable for use in a variety of test and measurement applications and systems. Key features include: 500 MHz maximum analog bandwidth. 1 Gigasample/second maximum digitizing rate (TDS 540A and 544A); 500 Megasamples/second maximum digitizing rate (TDS 520A and524A). Four channel acquisition the TDS 540A and 544A offer four full featured channels; the TDS 520A and 524A offer two full featured channels and two channels with limited vertical scale selections: 100mV, 1V, and 10V. Extensive triggering capabilities: such as edge, logic, and glitch. Video trigger (Option 05) is also available. The video trigger modes are NTSC, PAL, SECAM, HDTV, and FlexFormatTM (user definable format). Waveform Math Invert a single waveform and add, subtract, and multiply two waveforms. On the TDS 524A, 544A, and other TDS 500A equipped with option 2F, integrate or differentiate a single waveform or perform an FFT (fast fourier transform) on a waveform to display its magnitude or phase versus its frequency. Eight bit digitizers. Up to 15,000 point record length per channel (50,000 point with option 1M). Full GPIB software programmability. Hardcopy output using GPIB, RS232, or Centronics ports (RS232 and Centronics is standard on the TDS 524A and 544A and optional, as option 13, on the TDS 520A and 540A). Complete measurement and documentation capability. Intuitive graphic icon operation blended with the familiarity of traditional horizontal and vertical knobs. Online help at the touch of a button. A full complement of advanced functions, like continuously updated measurements, results and local pass/fail decision making. A complement of advanced acquisition modes such as peak detect, high resolution, sample, envelope, and average. The FastFrameTM feature acquires waveforms in rapid succession with a minimum of dead time between acquisitions. FastFrameTM allows acquisition rates of up to 50,000 frames per second. A unique graphical user interface (GUI), an onboard help mode, and a logical frontpanel layout which combine to deliver a new standard in usability. VGA output for driving remote monitors. A 1.44 Mbyte, DOS 3.3 or later, floppy disk drive for saving waveforms, color images, and oscilloscope setups (standard on the TDS 524A and 544A and optional, as option 1F, on the TDS 520A and 540A). Also, all TDS 500A have builtin NVRAM storage for saving waveforms and setups. User Interface Specialized display modes, such as variable persistence (with color coding on the TDS 524A and 544A), dot or vector mode, sin(x)/x or linear display filters, and, on the TDS 524A and 544A, user selectable color palettes. The Fit to Screen feature compresses the entire waveform record to fit on the screen. On the 524A and 544A, a color display for distinguishing among wave forms, their measurements, and associated text.