This circuit was found in old documentation. Operational amplifiers can be almost any type. Design formulas are given next to the diagram.
Found in Popular Electronics from the 90s, this signal tracer or tracer can be used with the inner...
In the circuit of the figure we used a potentiometer of 1 k ohm. We can use a larger...
This circuit was found in a 1966’s Delco Radio documentation. Transistors are from the era, high...