Third Order Low Pass Filter (CB25264E)

This circuit was found in the December 1990 issue of Radio Electronics magazine. It was used in a home theater sound system.

Parallel Resonance Oscillator (CB19209E)
We found this circuit in a European schematic manual from the 1980s. The circuit is still current, and...
Power Oscillator (CB12692E)
This circuit is basically the same configuration as the previous one with a power stage with...
70 V Regulator (CB21171E)
This positive voltage regulator with 70 V output was found in a National Semiconductor manual from...