[Elecraft] K3 APF

[Lyle Johnson]

The APF has a rapid 180 degree phase shift as you pass through its 
center frequency.  This is fine fore CW, but would wreak havoc on a 
PSK31 signal.  The K3s narrow filters (nomianl 50 Hz) are very good for 
local PSK31 decoding.  In addition, most PC-based software includes 
well-matched filters for PSK31 decoding.

The APF is really intended for CW operation only.

73,

Lyle KK7P

> What are the pro's and cons of implementing it for the digital modes too?