I just did a quick comparison of the rf noise generated by our 2006 vs. the 2010 Prius, and posted photos. It appears that Toyota worked at improving low frequency noise (hf spectrum). I haven't yet tried moving my sensing antenna around to look for variations in rf levels at different parts of the vehicles. This was done with an antenna centered on the roof. I initially thought there was noise coming from the vehicle at around 100MHz, but that now appears to have been FM radio signals.
That should mean that the 2010 has better AM radio reception than the Gen2. It would be difficult to have worse AM reception than my 2004. JeffD
Hi Snijd, That does look like a good improvement. HF Ham Radio from the 2010 might be possible. Yes, that massive set of "noise" centered on 100 MHz (nearly square shape near the center of the plots) are the mass of FM broadcast signals common in most metropolitan areas. When they do real EMI/RFI testing , its done either in an RF shielded chamber, lined with absortbtive tiles/carbon foam spikes, or in an outdoor site that is well away from metropolitan areas, preferably in a valley surround with steep terrain. There were comments out there, that the solar panel could not be hooked into the recharging the hybrid battery due to EMI/RFI problems in the developement. Although they did not succeed in that respect, the general EMI/RFI improvement is significant.
I've added new shots of the screen with a center frequency of 7.5MHz and span of 15MHz. I measured at the center of each roof, next to each inverter, and with the power off altogether. The most striking result is the noise level next to the older car's inverter.