Regardless of whether you build your own phase noise measurement setup from parts or whether you purchase an already complete system made by Agilent or others, you will still face the reality that there are only three ways to measure phase noise and you mentioned them in your previous email:
1. Start with a frequency source that is more than 10dB better phase noise than the one you want to measure. This is difficult when measuring a HP10811 2. Use two or three identical oscillators. This works if all are really the same but does not work if one of them is significantly different. 3. For measuring much poorer phase noise sources and for measuring further from the carrier than we are interested in, one uses a delay line discriminator. Having access to a calibrated commercial measurement system will not assist you at all unless you can find other oscillators that meet the criterion. Those systems do not contain the comparison signal sources unless you are measuring something with phase noise much poorer than the 10811. Then they are simply using a moderately low noise synthesised signal generator as one of the comparison sources. 73, Jeffrey Pawlan, WA6KBL IEEE, MTT and UFFC _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts