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

Function of the card:
CTDL-Two Way “And” PNP No Loads
Two-Way-AND (no loads)
Ctdl 2 way and pnp field replacement

Listed in 1401 SMS card usage

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

Part number: 371263

Field replacement part number: 370975

PCB number: 528991

Used in: IBM 1401, IBM 7070

Cap code: None (details)

Symbol: -A

-A: Negative AND. In-phase output is negative only when all inputs are negative. Out-of-phase output is positive for the above condition.
IBM SMS card type CG 371263 IBM SMS card type CG 371263 IBM SMS card type CG 371263 IBM SMS card type CG 371263 IBM SMS card type CG 371263 IBM SMS card type CG 371263

Image courtesy of Randall Neff
Image courtesy of Henk Stegeman

References: 1_2 SMS Cards, pp29,82
IBM Standard Modular System, Component Circuits, p42
Coslet data

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.