intuition for testing source in thevenin/norton

[nhrock3]

when i have a system of only dependant sources and i want to find its norton /thevenin
representation i need to add a testing source on the ports from whome we want to see the reaction

how to know that i should put a voltage source or current source
?

[CEL]

when i have a system of only dependant sources and i want to find its norton /thevenin
representation i need to add a testing source on the ports from whome we want to see the reaction

how to know that i should put a voltage source or current source
?

It is irrelevant. If you put a voltage source, you must evaluate how much current it supplies to the circuit in order to calculate its equivalent impedance. If you use a current source, you must evaluate the voltage across its terminals do do the same calculation.