Keysight Technologies N5290/1A PNA Series Service Manual page 50

System Tests and Adjustments
The N5290/1A Millimeter Test System Preliminary Check
Figure 3-8 Lifting the cable at the bend and watching for trace spikes/instability
7. Gently extend the head (exercising care to not overextend) and rotate side
to side (less than 90 degree) making sure traces are relatively stable and
still tracking each other. Refer to
Figure 3-9 Gently extending the head and exercise carefully so as not to overextend
8. Repeat steps
3-14
Figure 3-10 on page
1 through 7 as required for suspected faulty ports.
3-19.
Keysight N5290/1A Service Guide