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Tektronix TWD120
100 MHz, 100 MS/s 8-bit 2-ch digitizer
Tektronix TWD120

Produced from 1994 to 1995

Manuals – Specifications – Links – Pictures

The Tektronix TWD 120 Digitizer allows a Windows PC to be used as a digital storage oscilloscope. It is rated at 100 MHz, has two input channels and an external trigger input. It connects to the host PC via a SCSI bus.

The TWD 120 is about the size of a laptop, and was supplied with a soft case. It was intended to be used in conjunction with a laptop running Windows 3.1, and was apparently manufactured for GE for use by medical device field technicians.

The Adaptec ASPI SCSI driver is required for the software to communicate with the digitizer. SCSI configuration can be tricky.


     — Acquisition
Bandwidth 100 MHz (20 MHz selectable limit)
Sample rate 2 channels @ 100 MS/s each (two digitizers)
Resolution 8 bit
Record length 500 to 5000 samples per channel
Modes sample, envelope, average (16 samples), high-resolution, and peak-detect
     — Inputs
Deflection 2 mV/div - 99.5 mV/div (±1 V offset), 100 mV/div - 995 mV/div (±10 V offset), 1 V/div - 10 V/div (±100 V offset)
Max. input ±400 V (DC + peak AC) up to 100 kHz, derate −20 dB/decade up to 3 MHz, 13 Vp-p above 3 MHz
Input impedance 1 MΩ
     — Trigger
Trigger modes edge, error, external and video (NTSC, SECAM, PAL, Sync negative or positive)
Trigger Source CH1, CH2, External
Trigger coupling AC, noise reject, high frequency reject, low frequency reject
Trigger levels ±12 divisions (CH1, CH2) or up to ±15 V (External)
Trigger holdoff 500 ns to 10 s
     — Misc
Calibrator output 5 V @ 1 kHz (1 MΩ load)
Power 12−24 VDC, 30 W max