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

Function of the card:
SDTDL 2-way logic block low speed without loads
SDTDL-2 Way Logic Block Low Speed without Loads
SDTDL 2 way logic blk low sp w/o lds
4-2 way-no load

Listed in 1401 SMS card usage
Exists in SLT version.

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

Part number: 370379

SLT modules: 2399110

Customer Eng reference number: 729914

PCB number: 484027

Used in: IBM 1401, IBM 1410, IBM 2821 Control Unit, IBM 1311 Disk, IBM 1443 Printer

IBM SMS card type DGU 370379 IBM SMS card type DGU 370379 IBM SMS card type DGU 370379 IBM SMS card type DGU 370379 IBM SMS card type DGU 370379 IBM SMS card type DGU 370379 IBM SMS card type DGU 370379 IBM SMS card type DGU 370379 IBM SMS card type DGU 370379 IBM SMS card type DGU 370379

Image courtesy of Henk Stegeman
Image courtesy of Roberto Gonzalez Rocha

References: IBM 1311 ILD, p122
Coslet data
IBM 1443 ALD, p95
1410_SMS_VOL_1.pdf, p103
2_2 SMS Cards, pp84,85
IBM 2821 CCD, p51
This page created by Ken Shirriff on Wed Sep 15 18:15:10 2021.

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.