Tektronix TDS 400 Digitizing Oscilloscopes are portable instruments suitable for use in a variety of test and measurement applications and systems. Key features include: H Four input channels on the TDS 420 and TDS 460 (two input channels on the TDS 410), each with a record length of 500 to 15,000 points and 8-bit vertical resolution. (Option 1M extends the maximum record length to 60,000 points.) H Simultaneous acquisition of waveforms in all channels at the maximum digitizing rate of 100 Megasamples/second. All channels acquire at the full analog bandwidth of 150 MHz (TDS 410 and TDS 420) or 350 MHz (TDS 460) and all have the same features. H Video triggering capabilities (with Option 5, Video Trigger). H Full programmability and printer/plotter output. H Advanced functions, such as continuously updated measurements. H Specialized display modes, such as infinite and variable persistence. H A unique graphical user interface (GUI), an on-board help mode, and a logical front-panel layout which combine to deliver a new standard in usability. H Advanced waveform math (with Option 2F, Advanced DSP Math). Com- pute and display the integral of a waveform, the differential of a wave- form, and the FFT (Fast Fourier Transform) of a waveform.