This circuit uses a feedback integrator. We found it in Ferranti's transistor manual from 1974. Transistors are general-purpose types at the time.
With this circuit, signals in the range of 10 kHz to 150 kHz can be received at close to 4 MHz...
This limiting circuit with an operational amplifier has an adjustable cut-off point and can use...
Published by Philips in 1965 documentation, the sensor for this circuit is a common LDR. The...