This circuit is from the 1990 Motorola Data Databook. The circuit can be implemented with equivalent transistors. The power supply must be symmetrical.
The gain of the Operational Amplifier in the figure is given by the ratio between R1 and R2. In...
This circuit for the car can be found in other versions in this section. This is from an 80's...
This circuit was found in the December 1992 Radio Electronis magazine. R2 is an NTC, there is a...