This circuit with low-slip characteristics uses an operating system that is not very common today. The circuit can be designed with more modern operational and equivalent FETs.
Found in a 1968 Mullard manual, this circuit measures temperature by infrared radiation. The...
This test instrument was found in the April 1991 issue of Radio Electronics magazine. The circuit has...
This simple photometer was found in a 1977 Radio Shack manual. The sensor is a photocell, which can...