FAQs from Rohde & Schwarz

NRP-Z sensors, SCPI command: FETCH?

Question

When I send INIT:IMM and then FETCH?, I get a response similar to 4.079685e-010,0.000000e+000,0.000000e+000

Can you please explain the returned format?

Answer

The FETCH? command returns the measured power value.

Since some Rohde & Schwarz power sensor models can be configured to also return auxiliary values (min./max. or random/max.), the string returned by FETCH? contains three result values. If no auxiliary values have been configured, only the first value, which contains the average power, is used. In this case, the second and third values would always be 0.0.

If you want to learn more about auxiliary values, look up the SENS:AUX command in your sensor's operating manual.

However, bear in mind that not all sensors implement the SENS:AUX command.