Function of the card:
ALLOY LOAD RESISTOR - 40.2 ohm 2 W
Alloy-Load Resistor – 40.2Ω 2W
Alloy - Load Resistor - 40.2 Ohm 2W
Alloy-load resistor
Listed in 1401 SMS card usage
Quad Resistor 40.2ohm 2W
Germanium alloy transistors were an early type of transistor, faster than the earlier grown-junction transistors.
Part number: 371453
Used in: IBM 1620, IBM 1410, IBM 1401, IBM 1414 I/O Synchronizer, 1622
Symbol:R
R: Load. Provides proper terminating impedance or optimum coupling of one circuit to another at the correct operating voltage level.
Pinout:
 |
A R1A B R1B C R2A D R2B E R3A F R3B G R4A H R4B J K L M N P Q R |
1410_SMS_VOL_2.pdf, p79
Coslet data
IBM 1620 Instructional System Diagrams, p484
National Museum of Computing.
IBM 1620 FE Catalog
This page created by Ken Shirriff on Wed Sep 15 18:15:10 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.