This page describes the IBM SMS card "DHT", and is part of the SMS card database.

Function of the card:
SDTDL-H.S. Logic Inverter
SDTDL-h.s. logic inverter

Saturated Drift Transistor Diode Logic (SDTDL) is a form of Diode-transistor logic using faster drift-field transistors.

Part number: 372168

Used in: IBM 1311 Disk

Cap code: None (details)

References: National Museum of Computing.
IBM 1311 ILD, p127

The information on these pages comes from a variety of sources, especially old IBM documents on bitsavers.org, as well as information from the IBM 1401 restoration team, especially Tim Coslet's SMS data and Jim Hunt's data. Much of this information was obtained through OCR, so don't expect complete accuracy. These pages are not associated with IBM in any way.