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HUGH
10-23-2023, 11:05 AM
I have a horizontal delta loop of some 220ft x 158ft x (82ft across the far end). The wire was stranded copper of 4mm cross-sectional area (0.006 ins) with PVC coating. The height is 50ft so the feeder was about 40ft long of the same wire (coarse stranded for electrical wiring) and 8 inch spacing. The whole had about 6 ohms resistance.

This worked well for about 20 years but stretched considerably requiring hoisting up on the support pulleys each year. I was a little lax about the concentric fibreglass support pole at the shack end of about 2.5 inch diameter, only using one guy rope and a half-hearted "stiffener" halfway up to stop bowing. The copper was considerably heavy so naturally the pole eventually disintegrated in a storm so I thought of Kevlar-reinforced only to find that here it's only available in 50m lengths and it's quite expensive.

I bought some ultra-flexible steel wire with a PVC coating, it is much lighter but the antenna resistance is about 20 ohms and the feeder spacing (copper wire) is now 6 inches. I find the antenna current to be about half and the results comparatively inferior. Enquiries of some local hams showed some had tried galvanised steel fencing wire but I suspect these were not principally current fed like mine.

The new pole is the same 2.5 inch with 2 guy ropes in the proper place plus a "stiffener" (no comments please) about half-way up. Any comments welcome.

NQ6U
10-23-2023, 01:01 PM
Steel reinforced multi-strand copper wire is available but $$$ (or, in your case, £££). I have also seen copper plated steel wire, which was cheaper but even harder to find.

N8YX
10-23-2023, 01:10 PM
Copperweld is what you seek. Don't know if it's the same stuff Carl is referring to but it was designed for this sort of application.

K4PIH
10-25-2023, 09:07 AM
As long as it works. In the past I've used electric fence wire, scrap copper wire from a defunct telephone exchange,

HUGH
10-26-2023, 08:08 AM
"Copper" telephone wire would be good as here it's an alloy with steel (understandable). I know it's near impossible to solder. It isn't left "lying around" any more by the telephone companies".

HUGH
10-26-2023, 08:11 AM
I see now a copy of the Kevlar version has just become available in 100m lengths at a little under 1GBP per metre specially made for one on-line retailer. There's also a cheap one with effectively just one 22 gauge copper wire but it is very thin overall.

K4PIH
10-27-2023, 07:10 AM
When I used the scrap telephone hookup wire it was all in varying lengths. Some 2-3 feet long, some of it longer. Just end scraps from reels and clipped off short pieces from a wire run from one punch block to another. A lot of soldering to get enough for 2 legs of an 80 dipole but it worked really well. Found it in the inside plant area in a large Tuffy plastic garbage can, asked if I could have it.