This circuit for audio applications was found in an English magazine from the 80's. The circuit has a pass band below 3 kHz making it ideal for telecom applications.
We found this circuit in an old publication. The components used are rare today. Accuracy depends on...
This TTL circuit has a well-known configuration, having been found in a Radio Electronics magazine...
The circuit shown in the figure was suggested by National Semiconductor in its 1994 Linear...