Agilent Technologies Signal Analyzer N9030a - Manual (Page 524)

6 RLC Swept SA Measurement Front-Panel & SCPI Reference
AMPTD Y Scale
The “finer steps” advantage of the electronic attenuator is beneficial in optimizing the alignment
of the analyzer dynamic range to the signal power in the front panel as well as remote use. Thus,
you can achieve improved relative signal measurement accuracy. Compared to a mechanical
attenuator with 2 dB steps, the 1 dB resolution of the electronic attenuator only gives better
resolution when the odd-decibel steps are used. Those odd-decibel steps are less accurately
calibrated than the even-decibel steps, so one tradeoff for this superior relative accuracy is
reduced absolute amplitude accuracy.
Another disadvantage of the electronic attenuator is that the spectrum analyzer loses its “Auto”
setting, making operation less convenient.
Also, the relationship between the dynamic range specifications (TOI, SHI, compression and
noise) and instrument performance are less well-known with the electrical attenuator. With the
mechanical attenuator, TOI, SHI and compression threshold levels increase dB-for-dB with
increasing attenuation, and the noise floor does as well. With the electronic attenuator, there is an
excess attenuation of about 1 to 3 dB between 0 and 3.6 GHz, making the effective TOI, SHI, and
so forth, less well known. Excess attenuation is the actual attenuation relative to stated
attenuation. Excess attenuation is accounted for in the analyzer calibration
Elec Atten
Controls the Electronic Attenuator in dual attenuator configurations. This key does not appear in
single attenuator configurations, as the control of both the mechanical and electronic stages of the
single attenuator is integrated into the single Atten key.
Key Path AMPTD Y Scale, Attenuation
Remote Command [:SENSe]:POWer[:RF]:EATTenuation <rel_ampl>
[:SENSe]:POWer[:RF]:EATTenuation?
Notes Electronic Attenuation’s specification is defined only when Mechanical Attenuation is 6 dB.
Dependencies This key only appears in Dual Attenuator models with an Electronic Attenuator installed. It does
not appear in models with the Single Attenuator configuration, as in the single attenuator
configuration there is no “electronic attenuator” there is only a single integrated attenuator
(which has both a mechanical and electronic stage). However, in the single attenuator
configuration, EATT SCPI commands are accepted for compatibility with other X-series
instruments and set a “soft” attenuation as described in
"Attenuator Configurations and
Auto/Man" on page 521 . The “soft” attenuation is treated as an addition to the “main”
attenuation value set by the Atten softkey or the POW:ATT SCPI command and affects the total
attenuation displayed on the Attenuation key and the Meas Bar.
When Enable Elec Atten is off or grayed out, the Elec Atten key is grayed out.
Preset 0 dB
State Saved Saved in instrument state
Min 0 dB
524 Remote Language Compatibility Measurement Application Reference