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HUGH
11-07-2022, 06:18 AM
I had to replace a 160m horizontal loop (525 feet) and decided not to use the original 4mm (0.16 square inch) PVC-covered wire with tin-plated steel, mainly because of the weight of copper placing a huge strain on the supports which rely on trees. The Kevlar stuff would be superior but expensive. This steel wire is plastic-coated, non-kinking and is reasonably priced. The drawback is that the resistance is about 26 ohms versus the 8 ohms of the copper. Am I sacrificing power with this, the output currents on all bands may be quite a bit lower now?

I could have purchased thinner copper wire, say 2.5 mm PVC-covered, but wasn't sure if it would continue stretching or even break. I took great care to reinforce the ends where you'd expect the movement nodes to be.

The original came down as fibreglass pole broke after it's guy rope frayed through after about 18 years.

Hugh (M0DSZ)

PA5COR
11-07-2022, 07:46 AM
Copper will stretch and break over those long distances.
I even used thin stainless steel wire as antenna also higher Ohmic value, still did the job, use what stays up, picking up an antenna ends from the ground and redo them is no fun.

HUGH
11-07-2022, 05:10 PM
Thank you! I had to battle with reluctant trees as well and the XYL wasn't keen on me up long ladders even with a safety harness.

PA5COR
11-08-2022, 04:24 AM
My Fritzel FD-4 OCF is made off 2 mm stainless steel wire multicore and just 2 or 3 very thin copper wires interwoven in it, just came down because of the renovation after 20 yers on the roof...
STill strog, just the plastic covering of the wire desintegrated over time.
My loop for 160 set up for Jota/Joti was made of army telephone wire just temporary setup though, but did fine.