This circuit is from a 1968 documentation. It makes use of thermistors (NTC) to indicate overheating of charged batteries. Modern equivalent components can be used.
The gain for this circuit is given by the ratio between R2 and R1. The circuit is suggested by...
This receiver is from European documentation from the 90s. The integrated circuit is uncommon, and the coil...
Found in a 1970 EEE, this circuit can be applied to TTL ports. The supply is 5 V and the...