This circuit for equipment adjustment and diagnostics was found in a Mullard transistors manual from 1960. Information about the transformers is given with the diagram.
This timing circuit was found in old documentation. The technology is CMOS. The supply can be made...
This circuit was found in a 1967 General Electric documentation. Tunnel diodes can oscillate at very...
This circuit can be used in a signal level indicator with LEDs. The circuit is from an Electronics Now...