This signal injector and tracer (follower) was found in an old American documentation. The transistors can be general use and power is made with one or two common cells.
This circuit for PC and which can also be used with microcontrollers was found in an English...
This circuit is from National Semiconductor documentation. The operational amplifier is of the...
In this circuit we have the voltage multiplied by 5, obtaining between 50 and 80 V output when the...