Medium impedance stage (CB20563E)

We found this circuit in an English publication from 1963. The circuit uses germanium transistors of the time.

ON Semiconductor Phototransistor Output Optocouplers
ON Semiconductor Phototransistor Output Optocouplers Available from Mouser Electronics is the...
High Impedance Precision Rectifier (CB5097E)
This precision rectifier circuit is suitable for applications in an AC / DC converter. We find it...
Battery Step Up Switched Regulator (CB6065E)
This is a circuit suggested by Linear Technology in a 1980s documentation. The integrated circuit is from...