[time-nuts] Phase Noise Comparisons

[Rob Sherwood.]

I did some interpolation to compare the specs for phase noise of the 8660 the way it was done then to the present method. I think it is going to be something like -105 dBc/Hz to -110 dBc/Hz at 10 kHz offset at 14 MHz carrier frequency.



As a comparison, the 8662A is about -135 dBc/Hz and the 8642A is better than -150 dBc/Hz.

Actual measurements on multiple generators in my lab.  Unfortunately I have never used or measured an 8660.



3335A -128 dBc/Hz

3336C -120 dBc/Hz

3325A -115 dBc/Hz (original version.  Later improved by 4 pr 5 dB after the 3336C came out.)



As a comparison a Rigol DG4162 is -115 dBc/Hz All at 10 kHz offset and on the 20 meter band.



It depends what you are trying to measure. Sensitivity or noise floor, anything will work within the range of specified output accuracy and leakage.  On the other hand, if you are trying to measure the dynamic range of a receiver, or its phase noise characteristics, you cannot do that with most generators.



Rob, NC0B