[Elecraft] K3: KRX3 question

[David Woolley (E.L)]

Ed Muns wrote:

> What DSP bandwidths were you using and where did you have your crystal
> filters engaging?  There is only a 65 Hz bandwidth difference between the
> "400" and "250" crystal filters and both are wider than the what is needed
> for 170 Hz shift RTTY.  The crystal filter function is to protect the DSP

For clarity, 170Hz is less than the minimum required bandwidth for RTTY. 
  That needs to be extended by some multiple (> 1.0) of the baud rate, 
to avoid excessive truncation of significant sidebands.  I would suggest 
that a filter that was significantly down at 250 Hz would be introducing 
significant distortion.


-- 
David Woolley
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