This circuit lets through the 300 Hz to 3kHz range that corresponds to the human voice. We found it in the Radio Electronics magazine of February 1990. The circuit uses both parts of the LM381.
We find this circuit in an Electronic Design of the 90s. The used integrated circuit admits...
This multiple cable test sequential circuit was found in Radio Electronics. The connector must be...
This circuit provides precise signals of three frequencies, using CMOS technology. The integrated...