Function of the card:
CTDL-Translate Block NPN
II to T Converter
Listed in 1401 SMS card usage
Complemented Transistor Diode Logic (CTDL) is IBM's term for a form of diode-transistor logic.
Part number: 371258
PCB number: 491003
Used in: IBM 1401, 7030, IBM 7070
Symbol:C
C: Converter. Used to translate from one voltage level to another, or to change the amplitude of the voltage swing about the same reference level.
Image courtesy of Randall Neff
Coslet data
1_2 SMS Cards, p104
This page created by Ken Shirriff on Wed Sep 15 18:15:10 2021.
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.