Temperature controller (CB21286E)

Found in National Semiconductor documentation from the 1990s, this circuit can be implemented with equivalent modern components.

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2 to 9 kHz PLL Synthesizer (CB4566E)
We found this circuit at Modern Electronics in January 1991. The magazine no longer exists, but...
Bidirectional switch (CB9162E)
Found in a 90's EDN, this circuit can be used as a shield. The components depend on the MOSFETs...
Cooking Timer (CB18596E)
This circuit will trigger an audible warning signal after the end of the pre-programmed timing. Using...