As for foot note 3: I suspect that reasoning for mostly not using TTL inverter chips in eastern designs was limiting number of BOM entries and number of chip de

As for foot note 3: I suspect that reasoning for mostly not using TTL inverter chips in eastern designs was limiting number of BOM entries and number of chip designs that have to be manufactured in large volumes. Another thing is that in many designs the author just used random NPN transistor (selected on the basis of availability, so seeing RF power transistors used for almost anything was not that uncommon) and resistor. Edit: and to me, 134ЛА8 with it's connected inputs seems to be explicitly designed to be usable as either bus driver or invertor replacement. You would not want to use that in hand-optimized random combinatorial logic. Edit2: on the other hand I would not be too surprised if there was IBM SLT module that implements half of or even whole 134ЛА8 :)