Timed Alarm (CB6423E)

We found this circuit in a 90's Popular Electronics. The circuit produces a loud sound if S2 is not pressed to reset.

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Highly Sensitive Laser Alarm (CB25977E)
This circuit is more sensitive than the previous one, triggering when a laser beam that hits the...
Adjustable time chaser (CB6794E)
This circuit was obtained in a 1967 Electronics World. The components are still common today, the...
Touch Activated Motor II (CB1548E)
The simple touch of the fingers on a sensor causes this circuit to drive a motor that goes into...