Function of the card:
SDTDL 4-2 way plus a wo/load
Saturated Drift Transistor Diode Logic (SDTDL) is a form of Diode-transistor logic using faster drift-field transistors.
Part number: 372197
Customer Eng reference number: 734306
PCB number: 484027
Used in: IBM 2821 Control Unit
Cap code: None (details)
Symbol: +A
+A: Positive AND. in-phase output is positive only when all inputs are positive. Out-of-phase output is negative for the above condition.
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.