A network for performing a stimulus response experiment, for example to measure a propagation delay between different locations on an object contains a node apparatus and a further node apparatus. The node apparatus performs stimulus generation and a further node apparatus performs sensor data capture. The node apparatus comprises a handling circuit configured to control timing of stimulus generation based on a trigger signal. The experiment is prepared in a computer of the node apparatus. The computer supplies a command to a transmitter circuit to command the transmitter circuit to transmit a message to the further node apparatus. The transmitter circuit is used both to transmit the message in response to the command and to generate the trigger signal in a predetermined relation to a time of transmission of the message. Thus, accurate coordination timing is ensured in spite of possible inaccuracies in the preparation control circuit.