Function of the card:
Alloy – Driver, 48V, Light & Relay
Listed in 1401 SMS card usage
Germanium alloy transistors were an early type of transistor, faster than the earlier grown-junction transistors.
Part number: 371499
Used in: 7030, IBM 729II, IBM 7090
Cap code: None (details)
Symbol: DR
DR: Driver, Relay. Same as D with the device being driven identified as a relay.
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.