Found in Popular Electronics from the 90s, this circuit can be used in tachometers. The integrated circuit is not a common component today.
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...