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

Function of the card:
CTDL-Two Way “And” NPN
Two-Way+AND (all loads)
Ctdl two way and npn all loads

Complemented Transistor Diode Logic (CTDL) is IBM's term for a form of diode-transistor logic.

Part number: 371252

Field replacement part number: 370976

Customer Eng reference number: 729827

Used in: IBM 1401,IBM 7070

Cap code: WW (details)

Symbol:+A

+A: Positive AND. in-phase output is positive only when all inputs are positive. Out-of-phase output is negative for the above condition.

Family: CTDL

IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252 IBM SMS card type CHWW 371252

Image courtesy of Randall Neff

Image courtesy of Henk Stegeman

References:
1401 Pocket Reference Manual
IBM Standard Modular System, Component Circuits, p43.
1_2 SMS Cards, p30,31,32,89.
This page created by Ken Shirriff.

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.