This circuit, which can use the 4011 or 4001, was found in documentation from the 90s. The load depends on the transistor used, and the power supply must be isolated.
We found this circuit in a publication of 1990. With the changes it can be mounted easily today....
This simple photometer was found in a 1977 Radio Shack manual. The sensor is a photocell, which can...
This circuit is used to test a triac and also to teach how it works. The load is an incandescent...