Based on a unijunction transistor, this circuit was found in the January 1994 issue of Electronics Now magazine. The frequency range depends on C1, which can be changed.
This circuit allows you to use a calculator as a timer by directly activating a sum key with...
Found in American documentation from the 90s, this circuit has a timing system for activating the...
Found in an old American documentation this FM modulator makes use of a varactor diode. The...