Keysight U1271A, Service Manual

Page: 25 / 63

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.