This page describes the IBM SMS card "TNC", and is part of the SMS card database.

Function of the card:
SDTRL - SDTRL - 2 MC Oscillator

Open Collector 2MHz Crystal Oscillator (Note: probable errors in schematic for pins C and D)

Saturated Drift Transistor Resistor Logic (SDTRL) is a form of resistor-transistor logic using faster drift-field transistors.

Part number: 372231

Symbol:OSC

OSC: Oscillator. A free-running non-stable muitivibrator used to provide pulses of a given frequency and amplitude.

Pinout:

A O1
B R+
C R+
D RG
E
F
G
H
J GND
K
L
M -12V
N +12VM
P
Q
R
References: Coslet data

This page created by Ken Shirriff on Wed Sep 15 18:15:11 2021.

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.