Solar Oscillator (CB22262E)

This tiny photocell-powered audio oscillator was found in a book on transistors from the 1960s. The transistor is the famous germanium CK722.

High Efficiency Regulator 5 V x 1 A 723 (CB15332E)
This circuit is from Motorola's Linear Interface ICs from 1993. The MC1723 is the equivalent of...
0 to 20 V x 2A power supply (CB19215E)
This variable power supply circuit was found in a German publication from the 1980s. The circuit is...
High gain amplifier stage (CB20561E)
This audio amplifier stage was found in a 1963 publication. The circuit was designed to use...