Found in Popular Electronics from the 90s, this circuit generates signals in a frequency range set to R7 and basically determined by C1. Operational and equivalent transistors can be used.
Found in National Semiconductor documentation from the 90's, this circuit has an output current of...
With this circuit it is possible to raise the characteristics of a transistor by checking its gain...
The circuit presented is from the Linear Applications Handbook of the National Semiconductor of...