Found in a 1967 General Electric documentation, this meter uses Nixie tubes, popular at a time when LED and liquid crystal displays did not yet exist.
This circuit only detects variations in light falling on the sensor. The circuit uses an LM380 as a...
This is the well-known lightning lamp that was published in the March 1988 issue of Saber...
This photoelectric cell light relay was found in Radio Electronics magazine from April 1958. The...