This is an NPN switching circuit. If I understand it correctly, unless the input is connected to the +voltage source, the switch is off and no current should flow.
I tried this exact circuit with three different NPN transistors....each of which I successfully used as voltage amplifiers, and each one, put in this circuit, failed to restrict the current flow, unless I switched the load to between the emitter and ground.
Does somebody know why this is the case?
I am making an H-bridge and the NPN transistor must completely block the current flow when the load is on the collector side or it just can't work.
The transistors I tried were
TIP31C, TIP31AG, MPS3704