I Differential Input - Keysight x-series User Reference Manual

4 Input/Output Functions
Input/Output
imaginary part will always be zero, but for any other center frequency both the real and imaginary parts will
be significant. Note that since the receiver's real output is displayed as the "I" data, when the center
frequency is 0, the Q Only input appears as the "I" data.
Key Path
Example
Initial S/W Revision
I Setup
Access the channel setup parameters for the I channel.
Key Path
Initial S/W Revision

I Differential Input

Selects differential input on or off for the I channel. For differential input (also called balanced input), the
analyzer uses both main and complementary ports. When differential input is off (also called single-ended
or unbalanced input), the analyzer uses only the main port.
Key Path
Remote Command
Example
Notes
Couplings
Preset
State Saved
162
Input/Output, I/Q, I/Q Path
Set the input to be only the Q channel.
FEED:IQ:TYPE QONL
Prior to A.02.00
Input/Output, I/Q
Prior to A.02.00
Input/Output, I/Q, I Setup
:INPut:IQ[:I]:DIFFerential OFF|ON|0|1
:INPut:IQ[:I]:DIFFerential?
Put the I channel in Differential Input mode
INP:IQ:DIFF ON
When I Differential Input = On, the analyzer will check for attenuation mismatches between the I and
I-bar ports. If the difference in attenuation values exceeds 0.5 dB a Settings Alert error condition,
error 159 will be set.
When I Differential Input = On, and IQ Path is I+jQ, the Q Differential input must also be On.
Similarly, when I Differential Input = Off, and IQ Path is I+jQ, the Q 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 is not in use).
When Q Same as I is On, the value set for I will also be copied to Q.
Off
Yes
This is unaffected by a Preset but is set to the default value on a "Restore Input/Output Defaults" or
"Restore System Defaults->All"
EMI Receiver Mode Reference