Agilent Technologies X Series Manual page 423

Notes
Couplings
Preset
State Saved
Range
Initial S/W Revision
Q Input Z
Selects the input impedance for the Q channel. The impedance applies to both the Q and Q-bar ports.
The input impedance controls the hardware signal path impedance match. It is not used for converting
voltage to power. The voltage to power conversion always uses the Reference Z parameter. The
Reference Z parameter applies to both I and Q channels.
Key Path
Remote Command
Example
Notes
Couplings
When Differential Input = On, the analyzer will check for attenuation
mismatches between the Q and Q-bar ports. If the difference in attenuation
values exceeds 0.5 dB a Settings Alert error condition, error 159 will be set.
When Q Differential Input = On, and IQ Path is I+jQ, the I Differential input
must also be On. Similarly, when Q Differential Input = Off, and IQ Path is
I+jQ, the I Differential input must also be Off. If the states of the two inputs
do not match, an error condition message is generated, 159;Settings Alert;I/Q
mismatch:Differential.
Some active probes include built-in differential capability. When one of these
probes is sensed, this key is disabled. Since the differential capability is
handled in the probe, the Analyzer will use only the main port and the key will
show that the Analyzer's Differential Input mode is Off (indicating that the
complementary port not in use).
When a differential probe is not sensed and Q Same as I is On, the value set
for I will be copied to Q. This key is disabled when Q Same as I is On.
Off
On
This is unaffected by a Preset but is set to the default value on a "Restore
Input/Output Defaults" or "Restore System Defaults->All"
Off | On
Prior to A.02.00
Input/Output, I/Q, Q Setup
:INPut[1]:IQ:Q:IMPedance LOW|HIGH
:INPut[1]:IQ:Q:IMPedance?
Set the Q channel input impedance to 1 MΩ
INP:IQ:Q:IMP HIGH
LOW = 50 Ω, HIGH = 1 MΩ
When IQ Path is I+jQ, the I Input Z setting must be the same as the Q Input Z
setting. If the settings of the two inputs do not match, an error condition
message is generated, 159;Settings Alert;I/Q mismatch:Input Z.
Input impedance is a built-in characteristic of a probe. Therefore, whenever a
probe is sensed, this key is disabled and the value is set to match the probe.
When no probe is sensed and Q Same as I is On, the value set for I will also be
copied to Q. This key is disabled when Q Same as I is On.
Input/Output
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