Function of the card:
Ctrl-inverter "n" 2 way
Ctrl - inverter n 2 way
Ctrl-inverter 4 2 way
CTRL-Inverter "N" 2 Way Extender
CTRL Inverter "N" 2 Way
Crtl - inverter "n" 2 way
Listed in 1401 SMS card usage
Quad 2 Input Open Collector NAND
Part number: 371661
PCB number: 492867
Used in: IBM 1620, IBM 1410, IBM 729V, IBM 1311 Disk, IBM 1414 I/O Synchronizer, 7040, 1622, 1626
Symbol:O, E, A, O
Image courtesy of Henk Stegeman
Image courtesy of Roberto Gonzalez Rocha
Pinout:
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A I2 B I1 C O3 D I1 E I3 F I3 G O1 H I2 J GND K O4 L O2R M -12V N +12VM P O2C Q I4 R I4 |
Coslet data
IBM 1311 ILD, p134
1626 Plotter Parts
IBM 1620 Instructional System Diagrams, p485
National Museum of Computing.
IBM 1620 FE Catalog
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.