Function of the card:
CTRL-Inverters "N" Type Unloaded Collectors
Ctrl-inverters n type unloaded collectors
Triple 3 Input Open Collector NAND
Complemented Transistor Resistor Logic (CTRL) is IBM's term for a form of resistor-transistor logic.
Part number:371931
PCB number:491149
Used in:IBM 1620
Symbol:E, A, O
E: Extender. Provides additional inputs to logical blocks and triggers. Adds to drivers the ability to drive more loads.
Transistor type:033
References:
IBM 1620 Instructional System Diagrams, p475.
Pinout:
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A I1 B I1 C O2 D O3 E O1 F I2 G I2 H I2 J GND K I1 L PDR M -12V N +12VM P I3 Q I3 R I3 |
This page created by Ken Shirriff, 2015.
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. Images courtesy of Randall Neff. Much of this information was obtained through OCR, so don't expect complete accuracy. These pages are not associated with IBM in any way.
Creation time: Tue Mar 03 23:40:32 2015.