But I can measure and adjust power levels very accurately using this meter.
Erm, as long as there are no other signals at the output. I have several of those sensors with the 435b and the E4418B. Great power meters, but inherently broad band measuring everything from DC to 18ghz that is coming out of the unit and sum the power into one reading. The 4418B has a setting for frequency and most people think its for a selective measurement but alas it only changes the calibration factor. I always use them with band pass filters. I have a set for all frequencies I am interested with defined attenuation values I just add to the offset settings in the 4418.That way I know that my power actually is.
John Cunliffe W7ZQ