This simple clock can be used to generate signals up to 100 kHz, depending on the crystal. We found it in a 1967 documentation. Note the high supply voltage.
This timer was found in the Texas Instruments 1996 linear applications manual. The relay must be...
This circuit compares two light intensities, providing the indication on an analog instrument. The...
This circuit was obtained in a 1983 publication. It is a 1-transistor voltmeter, capable of...