HP 8590 E & L Series Spectrum Analyzers and HP 8591C Cable TV ...

CTA Convert to Absolute Units
Description
The result of the CTA command depends on the reference level, the current amplitude units,
and the amplitude scale (log or linear).
Measurement units are the internal binary data representation of measured results. The
internal binary data representation is 16-bit amplitude values that are stored in traces. The
values range from -32,768 to 32,767. The value of 8000 corresponds to an amplitude equal
to the reference level. In log mode, each count represents 0.01 dBm. A signal 0.01 dBm
above the reference level is at 8001, and a signal 1.0 dBm below the reference level is at 8000
minus 100, or 7900. In linear mode, 8000 is the reference level and 0 is the 0 volt level. If the
reference level is at 80 mV, each count would represent 0.080 divided by 8000 or 10 pV, but a
reference level of 2.4 volts would represent 2.4 divided by 8000 or 300 PV per count.
5-122 Programming Commands