[hpsdr] High Performance DDS Oscillator source

[Gerd Loch]

Grant,

meanwhile I received the information from AD that the phase noise of the DDS
itself would limit the total phase noise to a level which would make it not
be effective to minimize the phase noise of the clock oscillator to a very
low level:

<The exact oscillator doesn't really matter, as the noise pedalstal will be
dominated by the VCO on-board the <AD9912.

which does not mean that the noise level is not pretty low.

Do I understand the influence of noise of the DDS-oscillator in a
directconversion system correctly when roughly presuming that the noise in
the range of 100 Hz to 10KHz can result in noise in the audio range what you
hear (and see) and from 10kHz up to i.e. 196 kHz what you see on the
panadapter and noise and spurs above 200kHz can produce additional "mirror"
signals with real signals and spurs which can be received within the
receivers bandwidth?


73 Gerd, DJ8AY



 1187694237.0