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

Function of the card:
CTDL-Two Way “And” PNP One Load
Two-Way-AND (1 Load)
Ctdl two way and pnp one load

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

Part number: 371262

Field replacement part number: 370915

Customer Eng reference number: 729821

Used in: IBM 1401,IBM 7070

Cap code: VV (details)


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

Family: CTDL

IBM SMS card type CGVV 371262 IBM SMS card type CGVV 371262 IBM SMS card type CGVV 371262 IBM SMS card type CGVV 371262

Image courtesy of Randall Neff

1401 Pocket Reference Manual
IBM Standard Modular System, Component Circuits, p42.
1_2 SMS Cards, p29,83.
This page created by Ken Shirriff.

The information on these pages comes from a variety of sources, especially old IBM documents on, 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.