"dxAce" wrote in message
...

Or, you might believe the 1990's rather than the 1930's :-)


Looking at the opposite side, that of the way coax is used at the
transmission end, there are a number of relevant situations.

AM broadcast stations using series fed towers (those with an antenna tuning
unit to couple to the tower right above the base insulator) generally bury
the coax that feeds the ATU and tower. The reason is not for any kind of
additional isolation or insulation, but to keep the cable where falling ice
from the tower or guys, storm debris (in hurricane areas, particularly)
can't hit it, and to make it safer from vandalism.

Buried cable installs are also cheaper than the preferred system, which is a
set of poles, metal or wood, above the ground, with a metal bar or roof
above it to prevent ice damage. The advantage of above ground is that the
cable is accessible for repair or replacement in case of internal arcing and
more immune to digging by morons from the telco or electric utility.

Generally, the decision to bury is one of cost, not of RF.