Indicated for 12 V systems, this circuit was obtained in a 90s Siliconix documentation. The components used are from the time and current equivalents can be tested.
This well-known configuration was found in a 1982 publication. Other operational amplifiers can be...
Suggested by General Electric in 1965 documentation this circuit is intended for the 120 Vac...
Combined with the two previous circuits, we can create a simple multimeter with this circuit. The...