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

Function of the card:
P to N Converter, Type B (in-phase load)

Part number: 371309

Used in: IBM 7090

Cap code: ZY (details)

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.

References: IBM Standard Modular System, Component Circuits, p73
SMS Cap Code Templates & Index

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.