Function of the card:
SDTRL Single Shot Variable
SDTRL ss variable vm
SDTRL - single shot variable - vm
Open Collector Programmable Falling Edge Triggered One Shot w/ Pulldown
Saturated Drift Transistor Resistor Logic (SDTRL) is a form of resistor-transistor logic using faster drift-field transistors.
Part number:370291
PCB number:493103
Used in:IBM 1414 I/O Synchronizer,IBM 1410
Symbol:SS
SS: Single Shot. Provides a monostable output which can be pulsed into its quasi-stable state for a predetermined duration. with each input triggering pulse or triggering voltage change. Once triggered, the output pulse duration becomes independent of input time duration or amplitude.
Transistor type:101 033
References:
1410_SMS_VOL_1.pdf/1410_SMS_VOL_2.pdf, p1078.
1414 SMS Cards, p89.
Pinout:
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A I1R B I1C C D TC-0 E TC-C F TC-s G TC-f H TC-vs J GND K O1R L O1 M -12V N +12VM P Q R TC-m |
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.