This circuit is from a 1968 documentation using one of the first integrated circuits available at the time, the TAA370. The circuit is powered by 1.3 V using a 200 ohm handset.
This logic circuit can indicate both TTL (5 V) and CMOS (5 to 12 V) output levels, operating with...
The sensor of this circuit is an NTC with a resistance between 200 and 1000 ohms. The resistor R1 must...
This circuit was found in a 1980s documentation. The operational amplifier is of a common type at the...