IBM SMS card CW, part no 371534: description and details

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: IBM 7070, IBM 1410, IBM 1401, 7030

Cap code: None (details)

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.

Image courtesy of Eric Schlaepfer
Image courtesy of Arthur Dauzat
Image courtesy of Randall Neff
Image courtesy of Henk Stegeman
Image courtesy of Christoph Methfessel

References: 2_2 SMS Cards, pp4,5
1410_SMS_VOL_2.pdf, p89
Coslet data
IBM Standard Modular System, Component Circuits, pp60,61

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.

CW: Trigger