TCON::FROM 15602,TO 15602,TRSP, MUX
but had no joy, yielding an obtuse error message. So after bang my head against my desk and getting help from two co-workers I finally googled the machine and found "Chris Deputy's" page on Comcast with a command saying to loopback the ds0, but I knew it was actually to put in the cross-connect. Sure enough
TCON::FROM 15602,TO 15602,TRSP
is all it took.