To both - thanks for the responses.

To John - so by the other website saying the cable is 75 ohm, is that good or bad? The cost would not be that much difference if I used two dayton 25' cables with an adapter in the middle relative to the 50' cable. Since the spot where the adapter would end up will be inside my siding, do you have any idea if using black electrical tape to seal the connection would be OK or should I be just fine with the 50' cable in my link above?