Using two unijunction transistors, this circuit found in Electronics World generates linear sawtooth signals. The frequency depends on the capacitors being around 500 Hz.
This is a simple circuit to control a set of lamps from 3 different points. We found it in an old...
This circuit was found in a 1990 Electronics World magazine. The circuit can be mounted today by...
Using a 4046 PLL this circuit recognizes a 1.6 to 1.8 kHz tone by driving an output LED. The...