Surge protector CA3130 (CB22005E)

Found in an English documentation from 1977, this circuit activates a relay when the input voltage exceeds the value set in VR1.

90 to 150 MHz receiver (CB20230E)
This simple super-regenerative receiver was found in American documentation from the 1980s. The...
MOSFET Progressive Power Supply (CB19373E)
We have already explored this configuration in several projects on our website. What the circuit does...
Transformer Audio Output Stage (CB18304E)
This circuit with only one transistor was found in Japanese documentation from the 1960s. The...