This balance or balance circuit with phase inversion was found in documentation from the 90s. Transistors can be low noise equivalents like BC549.
This circuit with the PA7601 was found in a 1967 Philco-Ford documentation. The circuit has a pass...
This CMOS version of the force gauge was found in a 1983 publication. In the CMOS version, the...
Using the LM317 (or LM350), this circuit is based on precision regulatory components such as those...