Function of the card:
SDTDL relay driver latching
Part number: 372473
Customer Eng reference number: 734387
Used in: IBM 2821 Control Unit
Image courtesy of Henk Stegeman
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.