A method and a system for determining at least one contribution of at least one device under test (DUT) are described. The DUT may be part of a radio frequency (RF) device chain. The method includes capturing a first signal portion at a first node associated with an input of the DUT and capturing a second signal portion at a second node associated with an output of the DUT. The first signal portion and the second signal portion are captured quasi-simultaneously. The method may also include aligning the captured first signal portion and the captured second signal portion with each other temporally, and determining the contribution of the DUT by comparing the first signal portion and the second signal portion.