This Star Trek red alert circuit was found in the July 1990 issue of Radio Electronics magazine. The power transistor must be equipped with a heat sink.
This circuit, found in similar versions in other articles in this section, dynamically tests...
This circuit was found in a Popular Electronics from the 90s. The circuit uses TTL technology and...
The sensor for this light relay found in a 1967 Japanese magazine is a common photocell. The...