Bob, Using the approach you described I was able to verify the noise
floor of my initial measurement setup to be at -80dBc at 10Hz offset
from carrier and -100dBc above 1kHz with a strong peaks at 50Hz, 60Hz
and harmonics. This all with an RBW in the FFT of around 4Hz.
This level of noise is way
Hi
With an audio spectrum analyzer, and an RPD-1 mixer, and +10 dbm on
each side of the mixer …. you should be able to get away with about 20 db
of “preamp gain”. Yes, that’s dependent on exactly what analyzer you have.
The typical sound card may well need closer to 50 db of gain. That’s better
