[Elecraft] need digital for dummies

[John Wiener]

I've been using the K2 for about two months.  Had a few SSB QSO's but  
mostly CW.
Being new to modern ham radio, I've done some reading about PSK, etc  
but still don't see the big picture.

I use an iMac G4 and just downloaded MacLoggerDX.

What exactly do I need for PSK or Pactor or ??

As far as I can tell I need some software for the sound card and a  
TNC and proper cabling.  Please note that the iMac uses FireWire and  
USB (no serial port available).

If someone could lead me through the next few steps, I'd be very  
grateful!

John
AB8WH

PS, My 10-12 watts may not work them but I sure do hear a lot of DX  
on 40 and 30 meters!  Great receiver!
Israel, Croatia, Bulgaria, Germany and Outer Hebrides (Scotland) all  
within less than 2 hours...very interesting to follow the
Gray Line propagation on the DXLogger map as I listened on those  
bands.  Also heard Canary Islands (and subsequent pile-up!)