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

Function of the card:
SDTDL-Three 3-Way N And Logic Blocks without Loads
SDTDL three 3-way n and logic blocks without loads

Listed in 1401 SMS card usage

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

Part number: 370219

PCB number: 484029

Used in: IBM 1401, IBM 1311 Disk, IBM 1410


-A: Negative AND. In-phase output is negative only when all inputs are negative. Out-of-phase output is positive for the above condition.
IBM SMS card type DEJ 370219

References: 2_2 SMS Cards, pp74,75
IBM 1311 ILD, p113
Coslet data
1410_SMS_VOL_1.pdf, p36
This page created by Ken Shirriff on Wed Sep 15 18:15:11 2021.

The information on these pages comes from a variety of sources, especially old IBM documents on, 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.