Function of the card:
SDTDL memory .200 usec delay line
Saturated Drift Transistor Diode Logic (SDTDL) is a form of Diode-transistor logic using faster drift-field transistors.
Part number: 370250
PCB number: 493389 , hole pattern: 492672
Used in: IBM 1410, IBM 1311 Disk
Cap code: None (details)
Symbol: DLY
DLY: Delay. Delays a pulse for a certain specified constant time.
References: 1410_SMS_VOL_1.pdf, p63
IBM 1311 ILD, p120
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.