This commercial transistor tester circuit (EICO 666) is from a Japanese publication from the 1960s. The switch selects the types of test with the switching of the terminals and the gain ranges.
We found this circuit in a 1967 Experimenters Handbook. The circuit can be implemented with other...
This circuit is from an old documentation but can be implemented with a BD136 for Q1 and 2N3055 for...
In the figure we have the basic configuration of an inverter transconductance amplifier, as...