[TowerTalk] Old Hardline

[Ralston, William]

Mike -

I bought a 1000' spool of ½ inch hardline circa 2000 of unknown age (I don't recall the make, it wasn't Andrew, but it was compatible with the most common LDF4-50 connectors).  I did note there was some oxidation of the copper near the cut ends, but cut off a few inches or more to get to clean copper.

I wound up with two runs of approximately 430' each, and the loss measured out exactly as expected within the accuracy of my MFJ antenna analyzer.

I am still using a 130' piece of that hardline now, and it measures within 0.2 dB of expected (again, limited by the accuracy of the MFJ259B).

Assuming the jacket is intact and there aren't any kinks, it's probably fine at HF... can't speak to VHF.

I don't if there are any theoretical concerns with aging of the dielectric or chemical outgassing from the dielectric oxidizing the copper.  Any oxidation of the copper through the outer jacket is going to be on the outside of the cable, and thus not affect the electrical properties of the coax.

--Bill N7VM