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.
Found in a PE Hobbyst Handbook, this circuit checks if there is voltage in a power outlet by...
This circuit was found in an article in Electronics Now magazine from June 1998. The sensor...
This circuit generates an FM signal of 4.7 or 10.7 MHz for audio signals on analog TV or FM, with...