Flood alarm (CB7994E)

This circuit is from a 90s Popular Electronics. The transistors are of general use and the buzzer is a Sonalert type.

Infrared Shooting Target (CB18794E)
This is the target for the CB18793E infrared firing gun. The circuit can be powered by voltages from 5...
Trigger 7400 (CB19418E)
This TTL trigger circuit with the 7400 can be used as a signal conditioner in an input shield for...
Optical Trigger (CB4951E)
This basic circuit is from an old documentation. The relay must be 50 mA maximum and must have a...