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

Function of the card:
Current Mode, Coil Driver Power Inverter

Part number: 371498

Used in: IBM 7090


IP: Inverter, Power. Performs function of an inverter white also driving a line.
IBM SMS card type HS 371498 IBM SMS card type HS 371498

Image courtesy of Computer History Museum

References: IBM Standard Modular System, Component Circuits, p154
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, 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.