Suggested by Fairchild in a 1980s publication, this multiplier uses operational amplifiers from that time. The power supply must be symmetrical.
This circuit has a type of bias called "virtual earth" providing good gain, given by R2. The...
Found in a 1995 Hands On-Electronics, this circuit generates a sinusoidal signal whose frequency...
This circuit was obtained from a 1998s Popular Electronics. The magazine no longer exists, but the...