Jeff, I suspect that you mean modern day synthesisers rather than
specifically DDS. Actually, the DDS itself has quite low phase noise,
better than -130 dBc/Hz with Analog Devices chips, especially if the
internal multiplying PLL is not used in the reference path.
73, Greg. ZL3IX
On 2011-12-31 06:30 p.m., Jeff Blaine wrote:
> Phase noise is generated by the rig's LO and exists as a more broad band low
> level signal. Issue is more significant with modern day DDS than with older
> analog-type VFO sources. Guys who operate field day can relate...
>
> 73/jeff/ac0c
> www.ac0c.com
> alpha-charlie-zero-charlie
>
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