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

Function of the card:
Trigger
Ctdl trigger
CTDL-Trigger

Listed in 1401 SMS card usage

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

Trigger is IBM's term for a flip flop or latch.

Part number: 371534

PCB number: 493211 , hole pattern: 491450

Used in: 7030, IBM 1410, IBM 1401, IBM 7070

Symbol:T

T: Trigger. A conditioned bi-stable device whose steady-state outputs change from one stable state to the other with two separate triggering levels, pulses, or voltage changes. The set input turns the trigger on if the reset input Is not on, and vice versa.
IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534 IBM SMS card type CW 371534

Image courtesy of Randall Neff
Image courtesy of Eric Schlaepfer
Image courtesy of Henk Stegeman

References: 1410_SMS_VOL_2.pdf, p89
IBM Standard Modular System, Component Circuits, pp60,61
2_2 SMS Cards, pp4,5
Coslet data
This page created by Ken Shirriff on Sun Dec 16 16:11:05 2018.

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.