Im interested in topping/capping a peice of coax cable. I have a run that was "sniped" by our cable guy, but I want to put a cap on it so I can re-connect it to main cable run. <BR><BR>I've spliced ...

You have to use a VCR, or a cable box to tune the channel, and then output to RCA. AFAIK, that dongle is for digital audio.