We find this circuit in American documentation from the 1980s. It consists of a frequency folder using a varicap. The capacitors and coils depend on the frequency of operation.
This circuit is from an old documentation. Integrated circuit 723 is not common today. The power...
Figure 1 shows a circuit than can be used as time stage in timers, and other applications....
This stage circuitry for amplifying microphone signals makes use of germanium transistors as indicated...