[Elecraft] K3 & ADAT ADT-200A by HB9CBU

[David Woolley (E.L)]

Philip Covington wrote:
> On Tue, Dec 2, 2008 at 8:05 AM, David Woolley (E.L)

> 
> It may seem that way to you, but in real life it turns out the the DDS
> generates spurs due to only approximating a sin function, clock
> leakage, number of bits, etc...  There is not the same issue in the

There is no fundamental reason why the the DDS sine function should be 
any worse than the DSP one, nor for it to have any less bits than that 
with which the signal is digitised.

It might be that commonly used DDS chips are rather old technology, and 
you are comparing state of the art DSP with ten year old DDS.

> NCO generated LO in the FPGA in direct sampling receivers such as
> Perseus and QS1R.
> 


-- 
David Woolley
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