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

Function of the card:
Alloy-drivers read write vm
Alloy-Drivers, Read Write VM

Listed in 1401 SMS card usage

Germanium alloy transistors were an early type of transistor, faster than the earlier grown-junction transistors.

Part number: 371463

Used in: IBM 1401, IBM 1414 I/O Synchronizer

IBM SMS card type HN 371463 IBM SMS card type HN 371463

References: 2_2 SMS Cards, p19
Coslet data
This page created by Ken Shirriff.

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 self.data and Jim Hunt's self.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.