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

Function of the card:
Positive Binary Trigger Card 1
Alloy – Binary Trigger, P Type – Card #One

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

Trigger is IBM's term for a flip flop or latch.

Part number: 371413

Used in: 7030, IBM 7090

Symbol:+TB

+TB: Trigger (Binary). A trigger whose steady state outputs change upon the positive transition of the input.

References: IBM Standard Modular System, Component Circuits, pp106,107
Drawing courtesy of Living Computers: Museum + Lab
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 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.