This circuit was found in an 80's Electronic Design. It amplifies TTL fast signals for a coaxial cable. TTL is from the S (Schottky) line and transistors are types of the time.
This circuit is more sensitive than the previous one, triggering when a laser beam that hits the...
This circuit was obtained in a 1967 Electronics World. The components are still common today, the...
The simple touch of the fingers on a sensor causes this circuit to drive a motor that goes into...