This VCO with discrete components was found documentation from the 1980s. The central frequency with the indicated components is 8 kHz. A BC548 can be used for Q1.
Found in Ferranti's 1968 documentation, this circuit uses a Darlington photo transistor to drive a...
Found in documentation from the 70s, this circuit uses components from that time. Some of these...
This circuit monitors the state of a 12 V battery and can be used directly with one, or even in a...