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

Function of the card:
Inverter-load
SDTDL inverter low speed with load
Inverter Low Speed with Load
Inverter low speed with load
SDTRL inverter low speed with load

Listed in 1401 SMS card usage

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

Saturated Drift Transistor Resistor Logic (SDTRL) is a form of resistor-transistor logic using faster drift-field transistors.

Part number: 370348

Customer Eng reference number: 729921

PCB number: 747243

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

IBM SMS card type DHB 370348 IBM SMS card type DHB 370348 IBM SMS card type DHB 370348

References: Coslet data
1410_SMS_VOL_1.pdf, p87
IBM 1443 ALD, p100
2_2 SMS Cards, pp95,96
IBM 2821 CCD, p57
IBM 1311 ILD, p125
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 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.