"Highland Ham" wrote in message
...

snip

I would
recommend that you run the cables inside plastic (polyethylene) water
pipe instead of allowing the cables to be buried directly .You then can
use 'normal' coax including the 75 Ohms stuff used for satellite TV dish.
Where the pipe with cables come out of the ground make a 180 degree bend
such that the open end points downwards ,avoiding water ingress while
keeping an open vent preventing condensation inside the plastic pipe.

The plastic pipe also provides mechanical protection .

I also did a successful cable run inside plastic pipe. I used PVC 20 years
ago and not a problem since.

Some cable is advertised for "Direct Burial" but, based on the amount of
foot traffic over the area, I elected to use the pipe for the mechanical
protection. Pulling the cable was a tough job because I underestimated the
size pipe I needed. I finally had to cut the pipe and pull the cables in in
two sessions. I included a union in my final pull and cemented the halves
together before filling in the ditch.