[time-nuts] Re: DIY Low offset Phase Noise Analyzer (Erik Kaashoek)

[Erik Kaashoek]

Bob
This confuses me.
> The calibration of the system changes ( or can change ) each and every time you swap
> out signal sources. The levels are not going to be consistent setup to setup. Thus you
> calibrate each and every time you change out either device.
Assuming each source is saturating the mixer sufficiently (to be 
confirmed by measuring the output level of the source into 50 ohm) I do 
not understand how changing a source can change the calibration. Can you 
explain what is happening?
Please keep in mind I'm not after 0.1dBc/Hz accuracy, +/- 5dBc/Hz would 
already be great.
Erik.