Finding DirecTV Coax Cable

You don't care about your over-air-air cables or the associated booster as the satellite antenna has separate dedicated runs. Assuming that you actually do see 2 separate coax cables (plus a power cable) leaving the antenna on the roof, you can disconnect one coax on the roof and jam a piece of aluminum foil into the gap which will span the center conductor and the outside collar. Now, go inside with your multi-meter and look for a coax with a dead short. Once you have that coax, repeat the process on the 2nd roof antenna output. You now have both cables and you can do with them as you please. There are, of course, tools available to do the same thing (power at 1 end and signal at the other) but this is the "less than $1" solution.