Keysight M9391A PXIe Signal Analyzer & M9381A PXIe Vector Signal Generator 1 MHz to 3 GHz or 6 GHz
64
1.
a.
b.
2.
3.
a.
b.
If an existing instance of the SFP is connected to the reference module in a
shared (default) mode, and you try to connect a second instance of the SFP to
the same reference with ShareReferenceVisaSession=0 Advanced Option, you
will get the resource locked error shown above.
Synchronizing Multiple Chassis
When synchronizing multiple chassis, you must provide the same 10 MHz
frequency reference to the M9300A located in slot 10 of each chassis. You can
either use the 10 MHz
from the Keysight M9300A PXIe Frequency
OCXO Out
Reference master or an external 10 MHz frequency reference. The timing of the 10
MHz frequency reference is critical, so a symmetric splitter and equal length cables
should be used to split the 10 MHz and connect to the M9300A
connector in
Ref In
each chassis. Thus, if an external splitter is to be used, it must have sufficient level
to be split and drive both the Reference modules. Each M9300A must be in external
reference mode (
) and the OCXO Out (if used) must be
Use External Reference
enabled. The M9300A frequency locks an internal 100 MHz oscillator to the 10 MHz
frequency reference and divides the 100 MHz signal to create a local 10 MHz,
which is then routed to modules in the chassis using the PXIe backplane. This local
10 MHz signal does not have a guaranteed phase relationship to the 10 MHz
frequency reference provided through the Ref In connector. Therefore, before the
instruments in the chassis are initialized, select
to
Utilities > Align 10MHz Phase
align the 10 MHz Out with the 10 MHz frequency reference. This ensures that the
instruments initialize with aligned clocks. The alignment needs to be repeated
whenever the 10 MHz cabling is changed, whenever power is cycled, and once
every 24 hours to ensure the clocks don't drift.
Thus, the following steps need to be performed to align the 10 MHz Reference:
Before you power up the system, ensure that:
All channels are properly cabled.
OCXO out from reference in master chassis is split and provided to 10
MHz In on both reference modules using equal length cables.
Power up the system.
Run the SFP for the M9300A PXIe Frequency Reference in the master
chassis.
Turn OCXO out on.
Turn the External Reference on.
