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

Function of the card:
CTDL-Logic Inverter NPN All Loads
Cidl logic inverter npn no loads
CTDL Logic Inverter (NPN)
Ctdl logic inverter npn all loads

Listed in 1401 SMS card usage

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

Part number: 371079

Used in: IBM 1410, 7030, IBM 1414 I/O Synchronizer, IBM 7070, IBM 1401

Cap code: VB (details, details)

Symbol: I

I: Inverter. Changes a positive input to a negative output, or vice versa.
IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079 IBM SMS card type JMVB 371079

Image courtesy of Christoph Methfessel
Image courtesy of Randall Neff
Image courtesy of Henk Stegeman

References: IBM Standard Modular System, Component Circuits, p162
1410_SMS_VOL_2.pdf, p65
2_2 SMS Cards, p36
Coslet data
SMS Cap Code Templates & Index
1401 Pocket Reference Manual

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.