Here is a thought, if someone with a 8566 could reproduce my results by injecting a -20dBm 10 Mhz signal and setting the reference level to -20dB and set the scale to 1dB. Then with the signal generator start dropping the signal from -20dBm to -30dBm in 1dB increments. Does the trace start to fall off towards the bottom of the screen compared to 2dB and 5dB?
