Alternate Action Button

I am starting this month with some scans of circuits that I have used years ago that are still useful today. Hopefully the scans are clear enough.
By pressing S1 momentary switch, the 4069 hex inverter will cause the relay to turn on. When S1 is pressed again it will cause the relay to go off. This simple circuit can be used for the bases of many projects. The transistor in the circuit provides enough current to drive the relay.

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Electronic projects circuits