Calibration Procedures 1
Keysight U1270 Series Service Guide 25
Test Considerations
For optimum performance, all procedures should comply with the following 
recommendations:
– The performance verification test or adjustment should be performed under 
laboratory conditions where the ambient temperature can be controlled.
– The instrument should be put under the laboratory environment for at least 
1 hour.
– Ensure that the calibration ambient temperature is stable and is between 18 °C 
and 28 °C. Ideally the calibration should be performed at 23 °C ± 1 °C.
– Ensure that the ambient relative humidity is less than 80%.
– Allow a warm-up period of 3 minutes.
– Use a shielded twisted pair of PTFE-insulated cables to reduce settling and 
noise errors. Keep the input cables as short as possible. Long test leads can 
also act as antennas which may pick up AC signals.
– Connect the input cable shields to earth ground.