We found this circuit in a 1966 US documentation. It simulates a variable capacitor that can vary capacitance from 1,000 to 1. Transistors are general purpose types.
This circuit senses two-way currents serving to monitor battery charge and discharge. We find it...
This very low power circuit is based on the ICL7860. We found it in an Electronics Now from April...
This circuit can generate signals up to 5 MHz according the power supply voltage. Frequency is...