4093 Sine Square Converter (CB26335E)

Found in a Popular Electronics from the 90s, this circuit operates up to about 5 MHz input.

LT123 Low Voltage Linear Regulator (CB4399E)
The circuit presented is from the 1993 Linear Technology Applications. The components used were...
Appliance Protector (CB18105E)
This circuit time the activation of appliances and electronics when the power is cut, thus...
CW pickup (CB22328E)
This circuit is from an American publication from the 60's. The transistors are made of germanium. It...