[Elecraft] Operating my K3

[Telegrapher at att.net]

Been readin the mail about a variety of things associated with the K3.  It turly must be a wonder machine.  Mine is SN 763 and it must have some built in capabilities that i don't know about.

Everyone along with the book says that to run souncard related programs you should attach a cable from the line in and line out to the soundcard related jacks.  Well i'm telling you that must not be  necessary.  And i don't know why.  All i have hooked to my K3 is the RS-232 cable that goes to the PC for control and talking to the radio.  I'm using HRD for kicks.  Nothing connected to the Line out/Line in jacks at all.  Nothing from the speaker out nor phones out jacks.  And yet, i still see good displays when running the DM780 program.  I can copy PSK, RTTY and CW if i want.  Why?  How is this working unless it's going thru the RS-232 cable?  I'm not doing any transmitting yet on the digital modes but this is not supposed to happen from the way i understand it.  There must be some magic here that i don't understand.  Any suggestions other than to get analyzed?

Larry
W0OGH