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

Function of the card:
CTRL-Emitter Followers,Low Current [Photo Diode Sensor-DE]
Ctrl-emitter followers, low current

Quad Emitter Follower (Photodiode Amplifier)

Complemented Transistor Resistor Logic (CTRL) is IBM's term for a form of resistor-transistor logic.

Part number: 370720

Used in: IBM 1620

Cap code: None (details)

Symbol: AM

AM: Amplifier. Provides increased strength to a detected signal or pulse.
IBM SMS card type CBW 370720 IBM SMS card type CBW 370720

Pinout:

A O1
B I1
C O2
D I2
E O4
F O3
G I4
H I3
J
K
L +12V
M -12V
N
P
Q +12V
R
References: IBM 1620 Instructional System Diagrams, p488
Coslet data

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.