PSK is AFSK only. So it's trivial to build an interface that does both RTTY and PSK. FSK adds complexity. Not that I'm advocating this, as I use FSK on RTTY. 73 - Jim AD1C On 3/1/2009 2:58 PM, Jim W7RY wrote: > With today's modern rigs, there is no excuse for not using FSK. > > 73 > Jim W7RY -- Jim Reisert AD1C/Ø, <jjreisert at alum.mit.edu>, http://www.ad1c.us