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

Function of the card:
Alloy-Amplifier, Pre Sense Number 1

Listed in 1401 SMS card usage

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

Part number: 371899

Used in: IBM 1401

IBM SMS card type WX 371899 IBM SMS card type WX 371899

References: Coslet data
2_2 SMS Cards, pp61,62
This page created by Ken Shirriff on Wed Sep 15 18:15:11 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.