Topband: Outdoor cable trunking - opinions pse

[Dave G4GED]

Hi all,

I want to re-run all my TX and RX antenna feeders through trunking 
(detachable lid type), fixed along the bottom of a new 200ft timber fence.
This will give protection and future flexibility that burying or closed 
conduit methods wont.

The question is...to use galvanised steel or PVC?

I'm favouring steel because when earthed, I believe it will give extra 
noise screening for the RX feeders but are there any down sides such as 
"oven effects" in hot summer sun or "diode effects" between lids and 
sections, or any other problems?

PVC is a bit cheaper but wont offer the extra screening.

Does anyone have any relative experience please?

Thanks in advance.
Dave G4GED