I was able to clearly see a 500MHz -140dBm signal pretty cleanly (limit of my R&S SMHU gen (very nice gen, low cost), using -100dBm ref level and narrow span & BW.
Spectrum also measured within 1 dBm of the SMHU generator set to -140 dBm.
for option 04:
Outline:Real RMS detection with digital calculation
RBW :10Hz ~ 1MHz
Average noise level: RBW 10Hz, ATT 0dB
<-136.5dBm+1.5f(GHz) ;1MHz ~ 2.5GHz
< -132.5dBm+1.5f(GHz) ; 2.5GHz ~ 3.2GHz
< -128.5dBm ; 3.15GHz ~ 7.8GHz
< -119.5dBm ; 7.7GHz ~ 13.2GHz
for option 02:
Outline : Narrow resolution bandwidth with FFT
RBW : 1Hz ~ 1MHz
Average Noise Level: RBW=1Hz, ATT=0dB
< -146.5dBm+1.5f(GHz) ;1MHz ~ 2.5GHz
< -142.5dBm+1.5f(GHz); 2.5GHz ~ 3.2GHz
< -137.5dBm ; 3.15GHz ~ 7.8G
< -129.5dBm ; 7.7GHz ~ 13.2GHz
TO CALIBRATE JUST PRESS SHIFT CAL (LOOK AT THE NUMERIC KEYS)...it will take a few minutes...apply NO signal
THE UNCAL message is something else due to your settings...I had that too & at first thought it was a "CAL" issue, found it in the manual but can't remember what the correction was
Mine is a newer unit & also shows the 2000 year copyright but ver is 4.12 ...Anritsu website has download for core software (doesn't mention which version)
found it for you (in operator manual #2, page 137)
The spectrum traces on the screen are displayed as shown at the left according to the sweep time. The optimum sweep time gives a waveform like [1]. However,
a sweep time that is too fast decreases the waveform amplitude on the display as shown in [2] and [3]. Therefore, the apparent bandwidth gets wider, and the
frequency also shifts. When waveform [1] cannot be maintained, “UNCAL” is displayed.