Function of the card:
SDTRL Binary Trigger #2
Dual Gated Toggle Flip-Flop
Trigger is IBM's term for a flip flop or latch.
Saturated Drift Transistor Resistor Logic (SDTRL) is a form of resistor-transistor logic using faster drift-field transistors.
Part number:370809
Symbol:TB
TB: Trigger (Binary). A trigger whose steady state outputs change upon the transition of the input, i.e., usually going plus to minus, or sometimes going minus to plus.
Transistor type:101
Pinout:
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A RG1 B *S1 C Q2 D *Q2 E Q1 F SG1 G TP1 H *Q1 J GND K *R2 L SG2 M -12V N +12VM P *S2 Q RG2 R TP2 |
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 23:40:34 2015.