This circuit was obtained from an Electronic Design of 1968. The circuit uses components of the time that can eventually be exchanged for current equivalents.
We found this circuit in a publication from the 90's. The circuit is used with sinusoidal...
Ohmite TGHD non Inductive High Power Resistors Available in SOT-227 enclosures, these Ohmite...
Found in documentation from the 1980s, this circuit uses an operational amplifier from that time....