Coax question

[snapperq]

My scanner mast is on a tv tower which is about 62' up. A wind storm this week bent the base of the mast about 15 degrees. My question is when I redo my installation can I place the coax underground?
If so, how deep sould I go? I will have about a 100' run to my monitor. Will this work?
Advice would be apprecieated.

 

[jackj]

What coax are you planning to use? Some are rated for direct burial but others are not. Do you plan on burying the coax inside PVC pipe? In either case, you should bury it below the frost line. You should also use a coax that has low loss, 100 feet of RG-8 or -58 will have a lot of loss at UHF frequencies.

 

[snapperq]

I currently am using LMR 400 cable about 75'. I thought that could add an additional 25' and place in a pvc tube at about 2 to 3 feet undrground. Would this work?

 

[jackj]

That should work fine, snapperq. It won't make any difference what cable you use as long as it isn't in direct contact with the ground. Three feet should place it below the frost line in Northern Ohio. Be sure to seal the connection well, it's possible that the PVC pipe would develop a leak and fill with water.

100' of LMR 400's loss shouldn't be too bad. It is comparable to Belden's 9913 and I'm using 75' of that with good results.