Driver for oscillograph (T459E)

This circuit from an old MIT documentation excites an oscillograph element, an old waveform viewer.

Transistor Metronome (CB11939E)
This configuration has already been given in several articles and circuits on this website and...
High impedance comparator (CB5088E)
This circuit is from a Harris Semiconductor datasheet from the 80s. However the circuit can be...
Fast TTL Probe (CB1462E )
We found this logic level tester in a 1976 documentation. The circuit is powered by the voltage of the...