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System Functions
System
Off
Auto Align, Off disables automatic alignment and the maintenance of warranted operation, for the
benefit of maximum measurement throughput. With Auto Align set to Off, you are now responsible for
maintaining warranted operation by updating the alignments when they expire. The Auto Align, Alert
mechanism will notify you when alignments have expired. One solution to expired alignments is to
perform the Align All, Now operation. Another is to return the Auto Align selection to Normal.
The Auto Align, Off setting is rarely the best choice, because Partial gives almost the same improvement
in throughput while maintaining the warranted performance for a much longer time. The choice is
intended for unusual circumstances such as the measurement of radar pulses where you might like the
revisit time to be as consistent as possible.
When Auto Align, Off is selected the Auto Align Off time is initialized and the elapsed time counter
begins.
When Auto Align, Off is selected the Settings Panel indicates ALIGN OFF with a warning icon. The
warning icon is to inform the operator that they are responsible for maintaining the warranted operation
of the instrument:
All but RF
Auto Align, All but RF, configures automatic alignment to include or exclude the RF subsystem.
(Eliminating the automatic alignment of the RF subsystem prevents the input impedance from changing.
The normal input impedance of 50 ohms can change to an open circuit when alignments are being used.
Some devices under test do not behave acceptably under such circumstances, for example by showing
instability.) When Auto Align, All but RF ON is selected, the operator is responsible for performing an
Align Now, RF when RF-related alignments expire. The Auto Align, Alert mechanism will notify the
operator to perform an Align Now, All when the combination of time and temperature variation is
exceeded.
When Auto Align, All but RF ON is selected the Settings Panel indicates ALIGN AUTO/NO RF with a
warning icon (warning icon is intended to inform the operator they are responsible for the maintaining
the RF alignment of the instrument):
Readback Text: Partial
Initial S/W Revision: Prior to A.02.00
Key Path: System, Alignments, Auto Align
Mode: All
Example: :CAL:AUTO OFF
Notes: Auto Align Off begins the elapsed time counter for Auto Align Off time.
Couplings: Auto Align is set to Off if Restore Align Data is invoked.
Readback Text: Off
Initial S/W Revision: Prior to A.02.00
Key Path: System, Alignments, Auto Align