Function of the card:
Alloy-indicator driver 15 ma
CTDL Low Current Indicator Driver
Part number: 371528
IBM Standard Modular System, Component Circuits, p132
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.