[Elecraft] K3s Notch Filter

[Jim Brown]

On 5/12/2019 3:47 PM, Bob McGraw K4TAX wrote:
> Certainly will take out 1 or 2 signals and not affect others in the 
> 2.7 kHz BW of the normal FT-8 receiver bandwidth.

Not quite -- there's a lot of phase shift associated with the amplitude 
response change of the notch, so it degrades docoding of signals for 
some unknown bandwidth on both sides of the notch. K1JT warns against 
using any filtering ahead of the WSJT-X decoders for this reason.

73, Jim K9YC