This 5 V power supply for TTL, Shields and microcontrollers is old, and the components can be replaced by modern equivalents. Transistor Q1 can be a TIP31 and Q2 can be a BD135.
We have in the figure a traditional amplifier configuration with operational amplifier. The source...
This circuit was found in a 1977 Radio Shack documentation. The circuit is TTL, which must be...
This circuit is suitable for modulating small FM transmitters for eavesdropping or espionage. The...