This simple three-LED sensor uses an NTC at the input. The circuit is based on an uncommon integrated component today. We found it in documentation from the 80s.
This circuit was found in General Electric documentation from the 1980s. The circuit uses couplers...
We found this circuit on Motorola's 1993 Linear Interface ICs. Equivalent operational amplifiers can be...
The circuit in the figure is based on an LM101A; diodes can be replaced with equivalents. The...