Keysight N9000B - Page 686

3 VMA Mode
3.4 IQ Waveform Measurement
attenuator hardware setting until the input is changed back to the RF Input
For CXA-m with Option FSA (Fine-Step Attenuator or 2dB steps), the FSA-like behavior is only
available when the frequency setting is <=7.5GHz. So, when the frequency is changed from below
7.5GHz to above 7.5GHz, the attenuation setting changes to a multiple of 10dB that is no smaller
than the previous setting. For example, 4dB attenuation changes to 10dB
Preset Auto
The Auto value is 10dB
State Saved Saved in instrument state
Min 0dB
The attenuation set by this control cannot be decreased below 6dB with the knob or step keys. Values
below 6dB must be directly entered from the keypad or via SCPI. This protects against setting a
dangerously small attenuation value, which can put the instrument at risk of damage to input circuitry.
If the current mechanical attenuation is below 6dB, it can be increased with the knob and step keys,
but not decreased
Max
CXA Option 503 or 507 50dB
EXA 60dB
All other models 70dB
Note that in the Single-Attenuator configuration, the total of ATT and EATT cannot exceed 50dB. So, if
the EATT is set to 24dB first, the main attenuation cannot be greater than 26dB and will be reduced
accordingly; if the main attenuator is set to 40dB first, EATT cannot be greater than 10dB
Annotation The current value for Total Atten is displayed in the Measurement Bar at the top of the display. A value
appears for Electronic Attenuation only if the Electronic Attenuator is enabled. The annotation appears
as:
Atten: <total>dB (e<elec>)
The e letter is in amber in Single-Attenuator configurations
For example:
Dual-Attenuator configuration:
Atten: 24dB (e14)
Indicating the total attenuation is at 24dB and the electronic attenuation is at 14dB
Single-Attenuator configuration:
A: 24dB (e14)
Indicating the total attenuation is at 24dB and the “soft” attenuation is at 14dB (see below for
definition of “soft” attenuation)
When in Manual, a # sign appears in front of Atten in the annotation
Auto Function
Remote Command
[:SENSe]:POWer[:RF]:ATTenuation:AUTO OFF | ON | 0 | 1
[:SENSe]:POWer[:RF]:ATTenuation:AUTO?
Example Turn Auto Mech AttenON:
:POW:ATT:AUTO ON
Vector Modulation Analyzer Mode User's &Programmer's Reference 686