This circuit is from a 1974 publication by Motorola. The unijunction may be 2N2646 and bipolar BC558 and BC548. The pulse duration depends on the capacitor.
This stepper motor control was originally designed to use a PC's parallel port and is quite simple...
This is the traditional source using the LM317 3-terminal regulator circuit. The same source can...
This counter from 0 to 9999 was found in English documentation. The power source must be 5V with...