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

Function of the card:
N to P Converter (no loads)
Alloy-One Way “N” Block
Alloy-field replacement,am card

Listed in 1401 SMS card usage

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

Part number: 371203

Field replacement part number: 370904

PCB number: 491139

Used in: IBM 7090, IBM 7070, IBM 1401

Cap code: None (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.
IBM SMS card type AM 371203 IBM SMS card type AM 371203 IBM SMS card type AM 371203 IBM SMS card type AM 371203 IBM SMS card type AM 371203

Image courtesy of Christoph Methfessel
Image courtesy of Henk Stegeman

References: 1_2 SMS Cards, pp28,65
Coslet data

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.